Extracellular amyloid beta(Aβ) plaques are main pathological feature of Alzheimer’s disease.However,the specific type of neuro ns that produce Aβ peptides in the initial stage of Alzheimer’s disease are unknown.In...Extracellular amyloid beta(Aβ) plaques are main pathological feature of Alzheimer’s disease.However,the specific type of neuro ns that produce Aβ peptides in the initial stage of Alzheimer’s disease are unknown.In this study,we found that 5-hydroxytryptamin receptor 3A subunit(HTR3A) was highly expressed in the brain tissue of transgenic amyloid precursor protein and presenilin-1 mice(an Alzheimer’s disease model) and patients with Alzheimer’s disease.To investigate whether HTR3A-positive interneurons are associated with the production of Aβ plaques,we performed double immunostaining and found that HTR3A-positive interneurons were clustered around Aβ plaques in the mouse model.Some amyloid precursor protein-positive or β-site amyloid precursor protein cleaving enzyme-1-positive neurites near Aβ plaques were co-localized with HTR3A interneurons.These results suggest that HTR3A-positive interneurons may partially contribute to the generation of Aβ peptides.We treated 5.0-5.5-month-old model mice with tro pisetron,a HTR3 antagonist,for 8 consecutive weeks.We found that the cognitive deficit of mice was partially reversed,Aβ plaques and neuroinflammation we re remarkably reduced,the expression of HTR3 was remarkably decreased and the calcineurin/nuclear factor of activated T-cell 4 signaling pathway was inhibited in treated model mice.These findings suggest that HTR3A interneurons partly contribute to generation of Aβ peptide at the initial stage of Alzheimer’s disease and inhibiting HTR3 partly reve rses the pathological changes of Alzheimer’s disease.展开更多
In the first and second parts of this study,5-hydroxytryptamine(5HT)receptors,including 5-HT3 and 5-HT4 with the highest expression level,were found in clasp and sling fibres of the lower esophageal sphincter(LES).Spe...In the first and second parts of this study,5-hydroxytryptamine(5HT)receptors,including 5-HT3 and 5-HT4 with the highest expression level,were found in clasp and sling fibres of the lower esophageal sphincter(LES).Specific 5-HT3 and 5-HT4 receptor agonists can induce the contraction effect of clasp and sling fibres of the LES while specific 5-HT7 receptor agonists showed no effects.In the study of this part,the in-vitro muscle tension measurement technology and EFS methods were used to detect the effect of the selective 5-HT receptor antagonist on the clasp and sling fibres of the in-vitro LES under the electrical field stimulation(EFS),and further to ensure the effect of 5-HT receptor in the LES neuroregulatory pathway,and deeply explore the effect of 5-HT receptor in the systolic and diastolic function regulation of the LES.展开更多
AIM:To study the effects of 5-hydroxytryptamine(5-HT)receptor antagonists on normal colonic motor activity in conscious dogs.METHODS:Colonic motor activity was recorded using a strain gauge force transducer in 5 dogs ...AIM:To study the effects of 5-hydroxytryptamine(5-HT)receptor antagonists on normal colonic motor activity in conscious dogs.METHODS:Colonic motor activity was recorded using a strain gauge force transducer in 5 dogs before and after 5-HT2B,5-HT3 and 5-HT4 receptor antagonist administration.The force transducers were implanted on the serosal surfaces of the gastric antrum,terminal ileum,ileocecal sphincter and colon.Test materials or vehicle alone was administered as an intravenous bolus injection during a quiescent period of the whole colon in the interdigestive state.The effects of these receptor antagonists on normal gastrointestinal motor activity were analyzed.RESULTS:5-HT2B,5-HT3 and 5-HT4 receptor antagonists had no contractile effect on the fasting canine terminal ileum.The 5-HT3 and 5-HT4 receptor antagonists inhibited phaseⅢof the interdigestive motor complex of the antrum and significantly inhibited colonic motor activity.In the proximal colon,the inhibitory effect was dose dependent.Dose dependency,however,was not observed in the distal colon.The 5-HT2B receptor antagonist had no contractile effect on normal colonic motor activity.CONCLUSION:The 5-HT3 and 5-HT4 receptor antagonists inhibited normal colonic motor activity.The5-HT2B receptor antagonist had no contractile effect on normal colonic motor activity.展开更多
AIM: To investigate cellular 5-HT4(-h/+h) receptor distribution, particularly in the epithelial layer, by laser mi-crodissection and polymerase chain reaction (PCR) in porcine gastrointestinal (GI) tissues. METHODS: A...AIM: To investigate cellular 5-HT4(-h/+h) receptor distribution, particularly in the epithelial layer, by laser mi-crodissection and polymerase chain reaction (PCR) in porcine gastrointestinal (GI) tissues. METHODS: A stepwise approach was used to evaluate RNA quality and to study cell-specific 5-HT4 receptor mRNA expression in the porcine gastric fundus and colon descendens. After freezing, staining and laser microdissection and pressure catapulting (LMPC), RNA quality was evaluated by the Experion automated electrophoresis system. 5-HT4 receptor and glyceral-dehyde-3-phosphate dehydrogenase (GAPDH) expressions were examined by endpoint reverse transcription (RT)-PCR in mucosal and muscle-myenteric plexus (MMP) tissue fractions, in mucosal and MMP parts of hematoxylin and eosin (HE) stained tissue sections andin microdissected patches of the epithelial and circular smooth muscle cell layer in these sections. Pig gastric fundus tissue sections were also stained immunohisto-chemically (IHC) for enterochromaffin cells (EC cells; MAB352); these cells were isolated by LMPC and examined by endpoint RT-PCR. RESULTS: After HE staining, the epithelial and circular smooth muscle cell layer of pig colon descendens and the epithelial cell layer of gastric fundus were identified morphologically and isolated by LMPC. EC cells of pig gastric fundus were successfully stained by IHC and isolated by LMPC. Freezing, HE and IHC staining, and LMPC had no influence on RNA quality. 5-HT4 recep-tor and GAPDH mRNA expressions were detected in mucosa and MMP tissue fractions, and in mucosal and MMP parts of HE stained tissue sections of pig colon descendens and gastric fundus. In the mucosa tissue fractions of both GI regions, the expression of h-exon containing receptor [5-HT4(+h) receptor] mRNA was significantly higher (P<0.01) compared to 5-HT4(-h) re-ceptor expression, and a similar trend was obtained in the mucosal part of HE stained tissue sections. Large microdissected patches of the epithelial and circular smooth muscle cell layer of pig colon descendens and of the epithelial cell layer of pig gastric fundus, also showed 5-HT4 receptor and GAPDH mRNA expression. No 5-HT4 receptor mRNA expression was detected in gastric LMPC-isolated EC cells from IHC stained tissues, which cells were positive for GAPDH. CONCLUSION: Porcine GI mucosa predominantly expresses 5-HT4(+h) receptor splice variants, suggesting their contribution to the 5-HT4 receptor-mediated mu-cosal effects of 5-HT.展开更多
5-Hydroxytryptamine(5-HT)type 3 receptor(5-HT_(3)R)is the only type of ligand-gated ion channel in the 5-HT receptor family.Through the high permeability of Na+,K+,and Ca2+and activation of subsequent voltage-gated ca...5-Hydroxytryptamine(5-HT)type 3 receptor(5-HT_(3)R)is the only type of ligand-gated ion channel in the 5-HT receptor family.Through the high permeability of Na+,K+,and Ca2+and activation of subsequent voltage-gated calcium channels(VGCCs),5-HT_(3)R induces a rapid increase of neuronal excitability or the release of neurotransmitters from axon terminals in the central nervous system(CNS).5-HT_(3)Rs are widely expressed in the medial prefrontal cortex(mPFC),amygdala(AMYG),hippocampus(HIP),periaqueductal gray(PAG),and other brain regions closely associated with anxiety reactions.They have a bidirectional regulatory effect on anxiety reactions by acting on different types of cells in different brain regions.5-HT_(3)Rs mediate the activation of the cholecystokinin(CCK)system in the AMYG,and theγ-aminobutyric acid(GABA)“disinhibition”mechanism in the prelimbic area of the mPFC promotes anxiety by the activation of GABAergic intermediate inhibitory neurons(IINs).In contrast,a 5-HT_(3)R-induced GABA“disinhibition”mechanism in the infralimbic area of the mPFC and the ventral HIP produces anxiolytic effects.5-HT_(2)R-mediated regulation of anxiety reactions are also activated by 5-HT_(3)R-activated 5-HT release in the HIP and PAG.This provides a theoretical basis for the treatment of anxiety disorders or the production of anxiolytic drugs by targeting 5-HT_(3)Rs.However,given the circuit specific modulation of 5-HT_(3)Rs on emotion,systemic use of 5-HT_(3)R agonism or antagonism alone seems unlikely to remedy anxiety,which deeply hinders the current clinical application of 5-HT_(3)R drugs.Therefore,the exploitation of circuit targeting methods or a combined drug strategy might be a useful developmental approach in the future.展开更多
AIM： To delineate the mechanisms of renal vasoconstriction in hepatorenal syndrome （HRS）, we investigated the expression of type I inositol 1, 4, 5-triphosphate receptors （IP3R I） of kidney in mice with fulminant...AIM： To delineate the mechanisms of renal vasoconstriction in hepatorenal syndrome （HRS）, we investigated the expression of type I inositol 1, 4, 5-triphosphate receptors （IP3R I） of kidney in mice with fulminant hepatic failure （FHF）. METHODS： FHF was induced by lipopolysaccharide （LPS） in D-galactosamine （GAIN） sensitized BALB/c mice. There were 20 mice in normal saline （NS）-treated group, 20 mice in LPS-treated group, 20 mice in GaIN- treated group, and 60 mice in GalN/LPS-treated group （FHF group）. Liver and kidney tissues were obtained at 2, 6, and 9 h after administration. The liver and kidney specimens were stained with hematoxylin-eosin for studying morphological changes under light microscope. The expression of IP3R I in kidney tissue was tested by immunohistochemistry, Western blot and reverse transcription （RT）-PCR. RESULTS： Kidney tissues were morphologically normal at all time points in all groups. IP3R I proteins were found localized in the plasma region of glomerular mesangial cells （GMC） and vascular smooth muscle cells （VSMC） in kidney by immunohistochemical staining. In kidney of mice with FHF at 6 h and 9 h IP3R I staining was upregulated. Results from Western blot demonstrated consistent and significant increment of IP3R I expression in mice with FHF at 6 h and 9 h （t = 3.16, P 〈 0.05; t = 5.43, P 〈 0.01）. Furthermore, we evaluated IP3R I mRNA expression by RT-PCR and observed marked upregulation of IP3R I mRNA in FHF samples at 2 h, 6 h and 9 h compared to controls （t = 2.97, P 〈 0.05; t = 4.42, P 〈 0.01; t = 3.81, P 〈 0.01）. CONCLUSION： The expression of IP3R I protein increased in GMC and renal VSMC of mice with FHF, possibly caused by up-regulation of IP3R I mRNA.展开更多
A rabbit model of traumatic optic nerve injury, established by occlusion of the optic nerve using a vascular clamp, was used to investigate the effects of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid recep...A rabbit model of traumatic optic nerve injury, established by occlusion of the optic nerve using a vascular clamp, was used to investigate the effects of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist GYKI 52466 on apoptosis of retinal ganglion cells following nerve injury. Hematoxylin-eosin staining and a terminal deoxynucleotidyl transferase dUTP nick end labeling assay showed that retinal ganglion cells gradually decreased with increasing time of optic nerve injury, while GYKI 52466 could inhibit this process. The results demonstrate that following acute optic nerve injury, apoptosis of retinal ganglion cells is a programmed process, which can be inhibited by the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist.展开更多
Alzheimer’s disease (AD) is a progressive neurological disorder primarily affecting new memory formation as well as retrieval of previously acquired memories. According to World Health Organization, current global po...Alzheimer’s disease (AD) is a progressive neurological disorder primarily affecting new memory formation as well as retrieval of previously acquired memories. According to World Health Organization, current global population suffering from cognitive impairment is estimated to 37 million. The number is projected to double in next one and half decade. Half of the population afflicted with dementia is represented by AD patients. Current therapies, which provide marginal symptomatic relief to AD patients, are effective only in half of the patient population. In depth understanding of the molecular mechanism of the disease is urgently required to develop more effective therapies. Therapies in clinical development may either offer symptomatic relief to patients or provide pure disease modifications, thus limiting benefit to patients. 5-HT4 receptor agonists offer an attractive option for the treatment of AD patients. Activation of 5- HT4 receptor under preclinical conditions is demonstrated to improve neurotransmission and enhance the release of acetylcholine resulting in the memory formation. In various cell based and animal models, partial 5-HT4 receptor agonists are demonstrated to promote the release of soluble amyloid precursor protein alpha and block the release of amyloid beta peptide offering suitable candidates as disease modification agents. Remarkably, 5-HT4 receptor agonists are also reported to induce neurogenesis in hippocampus as well as enteric system through the activation of cyclic AMP response element binding protein in rodents. Taken together, 5-HT4 agonists address all major facets of Alzheimer’s disease and may provide therapeutic potential for other neurological disorders.展开更多
Persistent postsurgical pain is a serious issue in public health, which has received increased interest in recent years. Previous studies have reported that psychological factors promote the development of chronic pos...Persistent postsurgical pain is a serious issue in public health, which has received increased interest in recent years. Previous studies have reported that psychological factors promote the development of chronic postsurgical pain. However, it is unclear how chronification of postsurgical pain occurs. The α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor(AMPA) phosphorylation in the central nervous system plays a critical role in synaptic plasticity and contributes to central sensitization and chronic pain development. Here, we discuss the role of AMPA receptor regulation in stress-induced pain chronification after surgery.展开更多
Objective:Clinical and laboratory studies have demonstrated that prelimbic(PrL)and serotonin-4(5-HT4)receptors may have the key role in regulating anxiety.However,the pathophysiology of anxiety in Parkinson’s disease...Objective:Clinical and laboratory studies have demonstrated that prelimbic(PrL)and serotonin-4(5-HT4)receptors may have the key role in regulating anxiety.However,the pathophysiology of anxiety in Parkinson’s disease(PD)remains obscure.In this research,the effects of PrL 5-HT4 receptors on anti-anxiety behaviors in hemiparkinsonian rats were investigated.Methods:PD model rats were used as the research subjects,starting with behavioral changes,from the point of view of electrophysiology,the regulatory effect of PrL 5-HT4 receptors on PD-related anxiety and the possible mechanism were explored.Results:Anxiety-like behaviors were induced via MFB lesion in rats.Intra-PrL injection of 5-HT4 receptors agonist RS67333 induced anti-anxiety effects in both sham and PD group.In the sham group,PrL administration of 5-HT4 receptors antagonist SB204070 produce anti-anxiety effects,but in the PD group,the expression of anxiety-like behavior was increased.Compared to the sham group,the effective dose of the behavioral effects of the two drugs in the PD group was obviously higher.Electrophysiological data suggested that PrL administration of RS67333(SB204070)increased(decreased)the firing activities ofγ-aminobutyric acid(GABA)neurons in both groups.Compared with rats in sham group,lesioned rats had a shorter duration of the excitation(inhibition)effects on firing activities of GABA neurons.Conclusion:PrL 5-HT4 receptors regulate anxiety behaviors in PD rats,and its mechanism may be related to the down-regulation of expression or function of PrL 5-HT4 receptors in PD.展开更多
目的:从前额叶皮质、海马及下丘脑中5-羟色胺(5-hydroxytryptamine,5-HT)和5-羟色胺受体3(5-hydroxytryptamine receptor3,5-HTR3),5-羟色胺受体4(5-HTR4)角度探讨健脾化湿颗粒改善腹泻型肠易激综合征(diarrhea-predominant irritable b...目的:从前额叶皮质、海马及下丘脑中5-羟色胺(5-hydroxytryptamine,5-HT)和5-羟色胺受体3(5-hydroxytryptamine receptor3,5-HTR3),5-羟色胺受体4(5-HTR4)角度探讨健脾化湿颗粒改善腹泻型肠易激综合征(diarrhea-predominant irritable bowel syndrome,D-IBS)模型大鼠结肠运动和内脏敏感性的作用机制.方法:采用番泻叶灌胃结合束缚应激法建立D-IBS大鼠模型,应用健脾化湿颗粒进行干预,采用酶联免疫法(ELISA)检测大鼠海马中5-HT含量,采用免疫组织化学法检测前额叶皮质、海马及下丘脑中5-HT、5-HTR3、5-HTR4阳性表达,采用逆转录-聚合酶链反应法检测海马中5-H T R3 m R N A和5-H T R4m RNA的表达水平.结果:与正常组相比,模型组海马中5-HT含量(327.30±22.35 vs 265.33±13.60),前额叶皮质、海马、下丘脑中5-HT阳性表达(0.16±0.02 vs 0.08±0.01,0.19±0.02 vs 0.09±0.01,0.17±0.02 vs 0.08±0.01)明显升高(P<0.01);前额叶皮质、海马、下丘脑中5-HTR3阳性表达(0.29±0.02 vs 0.10±0.01,0.23±0.02 vs 0.09±0.01,0.22±0.02 vs 0.09±0.02)及5-HTR4阳性表达(0.25±0.02 vs0.11±0.01,0.28±0.02 vs 0.10±0.02,0.27±0.02 vs 0.11±0.02)明显升高(P<0.01);海马中5-H T R3 m R N A和5-H T R4 m R N A的表达(0.54±0.01 vs 0.17±0.05,0.73±0.08 vs 0.10±0.02)显著升高(P<0.01).与模型组相比,阳性对照组、中、高剂量组海马中5-H T含量(298.92±12.16、286.29±24.43、279.86±20.05 vs 327.30±22.35)显著下降(P<0.05,P<0.01),中、高剂量组前额叶皮质中5-HT表达(0.12±0.01、0.11±0.01 vs 0.16±0.02)显著下降(P<0.01),阳性对照组、中、高剂量组海马、下丘脑中5-H T表达显著下降(P<0.05,P<0.01);各治疗组前额叶皮质、海马、下丘脑中5-H T R3表达及5-H T R4表达下降显著(P<0.05,P<0.01);各治疗组海马中5-H T R3 m R N A表达及5-H T R4 m R N A表达显著降低(P<0.05,P<0.01).结论:健脾化湿颗粒可能通过下调脑中5-HT、5-HTR3、5-HTR4表达来改善D-IBS模型大鼠结肠运动和内脏敏感性.展开更多
基金supported by the Notional Natural Science Foundation of China,Nos.81371213 and 8107098 7the Natural Science Foundation of Shanghai,No.21ZR1468400 (all to QLY)。
文摘Extracellular amyloid beta(Aβ) plaques are main pathological feature of Alzheimer’s disease.However,the specific type of neuro ns that produce Aβ peptides in the initial stage of Alzheimer’s disease are unknown.In this study,we found that 5-hydroxytryptamin receptor 3A subunit(HTR3A) was highly expressed in the brain tissue of transgenic amyloid precursor protein and presenilin-1 mice(an Alzheimer’s disease model) and patients with Alzheimer’s disease.To investigate whether HTR3A-positive interneurons are associated with the production of Aβ plaques,we performed double immunostaining and found that HTR3A-positive interneurons were clustered around Aβ plaques in the mouse model.Some amyloid precursor protein-positive or β-site amyloid precursor protein cleaving enzyme-1-positive neurites near Aβ plaques were co-localized with HTR3A interneurons.These results suggest that HTR3A-positive interneurons may partially contribute to the generation of Aβ peptides.We treated 5.0-5.5-month-old model mice with tro pisetron,a HTR3 antagonist,for 8 consecutive weeks.We found that the cognitive deficit of mice was partially reversed,Aβ plaques and neuroinflammation we re remarkably reduced,the expression of HTR3 was remarkably decreased and the calcineurin/nuclear factor of activated T-cell 4 signaling pathway was inhibited in treated model mice.These findings suggest that HTR3A interneurons partly contribute to generation of Aβ peptide at the initial stage of Alzheimer’s disease and inhibiting HTR3 partly reve rses the pathological changes of Alzheimer’s disease.
基金Effect of 5-hydroxytryptamine Receptor in the Lower Esophageal Sphincter Regulation Mechanism(Number:18ZF23)。
文摘In the first and second parts of this study,5-hydroxytryptamine(5HT)receptors,including 5-HT3 and 5-HT4 with the highest expression level,were found in clasp and sling fibres of the lower esophageal sphincter(LES).Specific 5-HT3 and 5-HT4 receptor agonists can induce the contraction effect of clasp and sling fibres of the LES while specific 5-HT7 receptor agonists showed no effects.In the study of this part,the in-vitro muscle tension measurement technology and EFS methods were used to detect the effect of the selective 5-HT receptor antagonist on the clasp and sling fibres of the in-vitro LES under the electrical field stimulation(EFS),and further to ensure the effect of 5-HT receptor in the LES neuroregulatory pathway,and deeply explore the effect of 5-HT receptor in the systolic and diastolic function regulation of the LES.
文摘AIM:To study the effects of 5-hydroxytryptamine(5-HT)receptor antagonists on normal colonic motor activity in conscious dogs.METHODS:Colonic motor activity was recorded using a strain gauge force transducer in 5 dogs before and after 5-HT2B,5-HT3 and 5-HT4 receptor antagonist administration.The force transducers were implanted on the serosal surfaces of the gastric antrum,terminal ileum,ileocecal sphincter and colon.Test materials or vehicle alone was administered as an intravenous bolus injection during a quiescent period of the whole colon in the interdigestive state.The effects of these receptor antagonists on normal gastrointestinal motor activity were analyzed.RESULTS:5-HT2B,5-HT3 and 5-HT4 receptor antagonists had no contractile effect on the fasting canine terminal ileum.The 5-HT3 and 5-HT4 receptor antagonists inhibited phaseⅢof the interdigestive motor complex of the antrum and significantly inhibited colonic motor activity.In the proximal colon,the inhibitory effect was dose dependent.Dose dependency,however,was not observed in the distal colon.The 5-HT2B receptor antagonist had no contractile effect on normal colonic motor activity.CONCLUSION:The 5-HT3 and 5-HT4 receptor antagonists inhibited normal colonic motor activity.The5-HT2B receptor antagonist had no contractile effect on normal colonic motor activity.
基金Supported by Grant G.0061.08 from the Fund for Scientific Research Flanders
文摘AIM: To investigate cellular 5-HT4(-h/+h) receptor distribution, particularly in the epithelial layer, by laser mi-crodissection and polymerase chain reaction (PCR) in porcine gastrointestinal (GI) tissues. METHODS: A stepwise approach was used to evaluate RNA quality and to study cell-specific 5-HT4 receptor mRNA expression in the porcine gastric fundus and colon descendens. After freezing, staining and laser microdissection and pressure catapulting (LMPC), RNA quality was evaluated by the Experion automated electrophoresis system. 5-HT4 receptor and glyceral-dehyde-3-phosphate dehydrogenase (GAPDH) expressions were examined by endpoint reverse transcription (RT)-PCR in mucosal and muscle-myenteric plexus (MMP) tissue fractions, in mucosal and MMP parts of hematoxylin and eosin (HE) stained tissue sections andin microdissected patches of the epithelial and circular smooth muscle cell layer in these sections. Pig gastric fundus tissue sections were also stained immunohisto-chemically (IHC) for enterochromaffin cells (EC cells; MAB352); these cells were isolated by LMPC and examined by endpoint RT-PCR. RESULTS: After HE staining, the epithelial and circular smooth muscle cell layer of pig colon descendens and the epithelial cell layer of gastric fundus were identified morphologically and isolated by LMPC. EC cells of pig gastric fundus were successfully stained by IHC and isolated by LMPC. Freezing, HE and IHC staining, and LMPC had no influence on RNA quality. 5-HT4 recep-tor and GAPDH mRNA expressions were detected in mucosa and MMP tissue fractions, and in mucosal and MMP parts of HE stained tissue sections of pig colon descendens and gastric fundus. In the mucosa tissue fractions of both GI regions, the expression of h-exon containing receptor [5-HT4(+h) receptor] mRNA was significantly higher (P<0.01) compared to 5-HT4(-h) re-ceptor expression, and a similar trend was obtained in the mucosal part of HE stained tissue sections. Large microdissected patches of the epithelial and circular smooth muscle cell layer of pig colon descendens and of the epithelial cell layer of pig gastric fundus, also showed 5-HT4 receptor and GAPDH mRNA expression. No 5-HT4 receptor mRNA expression was detected in gastric LMPC-isolated EC cells from IHC stained tissues, which cells were positive for GAPDH. CONCLUSION: Porcine GI mucosa predominantly expresses 5-HT4(+h) receptor splice variants, suggesting their contribution to the 5-HT4 receptor-mediated mu-cosal effects of 5-HT.
基金supported by the National Natural Science Foundation of China(Nos.82071516,32171065,91949105,and 81771227)the Innovation Capability Support Program of Shannxi Province in China(No.2020TD-037)the Fundamental Research Funds for the Central Universities(Nos.GK202105001,GK202205019,and CK202205022),China.
文摘5-Hydroxytryptamine(5-HT)type 3 receptor(5-HT_(3)R)is the only type of ligand-gated ion channel in the 5-HT receptor family.Through the high permeability of Na+,K+,and Ca2+and activation of subsequent voltage-gated calcium channels(VGCCs),5-HT_(3)R induces a rapid increase of neuronal excitability or the release of neurotransmitters from axon terminals in the central nervous system(CNS).5-HT_(3)Rs are widely expressed in the medial prefrontal cortex(mPFC),amygdala(AMYG),hippocampus(HIP),periaqueductal gray(PAG),and other brain regions closely associated with anxiety reactions.They have a bidirectional regulatory effect on anxiety reactions by acting on different types of cells in different brain regions.5-HT_(3)Rs mediate the activation of the cholecystokinin(CCK)system in the AMYG,and theγ-aminobutyric acid(GABA)“disinhibition”mechanism in the prelimbic area of the mPFC promotes anxiety by the activation of GABAergic intermediate inhibitory neurons(IINs).In contrast,a 5-HT_(3)R-induced GABA“disinhibition”mechanism in the infralimbic area of the mPFC and the ventral HIP produces anxiolytic effects.5-HT_(2)R-mediated regulation of anxiety reactions are also activated by 5-HT_(3)R-activated 5-HT release in the HIP and PAG.This provides a theoretical basis for the treatment of anxiety disorders or the production of anxiolytic drugs by targeting 5-HT_(3)Rs.However,given the circuit specific modulation of 5-HT_(3)Rs on emotion,systemic use of 5-HT_(3)R agonism or antagonism alone seems unlikely to remedy anxiety,which deeply hinders the current clinical application of 5-HT_(3)R drugs.Therefore,the exploitation of circuit targeting methods or a combined drug strategy might be a useful developmental approach in the future.
基金Supported by National Natural Science Foundation of China, No. 30270607
文摘AIM： To delineate the mechanisms of renal vasoconstriction in hepatorenal syndrome （HRS）, we investigated the expression of type I inositol 1, 4, 5-triphosphate receptors （IP3R I） of kidney in mice with fulminant hepatic failure （FHF）. METHODS： FHF was induced by lipopolysaccharide （LPS） in D-galactosamine （GAIN） sensitized BALB/c mice. There were 20 mice in normal saline （NS）-treated group, 20 mice in LPS-treated group, 20 mice in GaIN- treated group, and 60 mice in GalN/LPS-treated group （FHF group）. Liver and kidney tissues were obtained at 2, 6, and 9 h after administration. The liver and kidney specimens were stained with hematoxylin-eosin for studying morphological changes under light microscope. The expression of IP3R I in kidney tissue was tested by immunohistochemistry, Western blot and reverse transcription （RT）-PCR. RESULTS： Kidney tissues were morphologically normal at all time points in all groups. IP3R I proteins were found localized in the plasma region of glomerular mesangial cells （GMC） and vascular smooth muscle cells （VSMC） in kidney by immunohistochemical staining. In kidney of mice with FHF at 6 h and 9 h IP3R I staining was upregulated. Results from Western blot demonstrated consistent and significant increment of IP3R I expression in mice with FHF at 6 h and 9 h （t = 3.16, P 〈 0.05; t = 5.43, P 〈 0.01）. Furthermore, we evaluated IP3R I mRNA expression by RT-PCR and observed marked upregulation of IP3R I mRNA in FHF samples at 2 h, 6 h and 9 h compared to controls （t = 2.97, P 〈 0.05; t = 4.42, P 〈 0.01; t = 3.81, P 〈 0.01）. CONCLUSION： The expression of IP3R I protein increased in GMC and renal VSMC of mice with FHF, possibly caused by up-regulation of IP3R I mRNA.
基金The Foundation of Xinjiang Uygur Autonomous Region in China, No. 200821137the National Natural Science Foundation of China, No. 81160153
文摘A rabbit model of traumatic optic nerve injury, established by occlusion of the optic nerve using a vascular clamp, was used to investigate the effects of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist GYKI 52466 on apoptosis of retinal ganglion cells following nerve injury. Hematoxylin-eosin staining and a terminal deoxynucleotidyl transferase dUTP nick end labeling assay showed that retinal ganglion cells gradually decreased with increasing time of optic nerve injury, while GYKI 52466 could inhibit this process. The results demonstrate that following acute optic nerve injury, apoptosis of retinal ganglion cells is a programmed process, which can be inhibited by the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor antagonist.
文摘Alzheimer’s disease (AD) is a progressive neurological disorder primarily affecting new memory formation as well as retrieval of previously acquired memories. According to World Health Organization, current global population suffering from cognitive impairment is estimated to 37 million. The number is projected to double in next one and half decade. Half of the population afflicted with dementia is represented by AD patients. Current therapies, which provide marginal symptomatic relief to AD patients, are effective only in half of the patient population. In depth understanding of the molecular mechanism of the disease is urgently required to develop more effective therapies. Therapies in clinical development may either offer symptomatic relief to patients or provide pure disease modifications, thus limiting benefit to patients. 5-HT4 receptor agonists offer an attractive option for the treatment of AD patients. Activation of 5- HT4 receptor under preclinical conditions is demonstrated to improve neurotransmission and enhance the release of acetylcholine resulting in the memory formation. In various cell based and animal models, partial 5-HT4 receptor agonists are demonstrated to promote the release of soluble amyloid precursor protein alpha and block the release of amyloid beta peptide offering suitable candidates as disease modification agents. Remarkably, 5-HT4 receptor agonists are also reported to induce neurogenesis in hippocampus as well as enteric system through the activation of cyclic AMP response element binding protein in rodents. Taken together, 5-HT4 agonists address all major facets of Alzheimer’s disease and may provide therapeutic potential for other neurological disorders.
基金Supported by The National Institute of Dental and Craniofacial Research Grants,Nos.R01 DE022880 and K02 DE023551
文摘Persistent postsurgical pain is a serious issue in public health, which has received increased interest in recent years. Previous studies have reported that psychological factors promote the development of chronic postsurgical pain. However, it is unclear how chronification of postsurgical pain occurs. The α-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid receptor(AMPA) phosphorylation in the central nervous system plays a critical role in synaptic plasticity and contributes to central sensitization and chronic pain development. Here, we discuss the role of AMPA receptor regulation in stress-induced pain chronification after surgery.
基金Key Research and Development Program of Shaanxi Province(2021SF-288)Natural Science Basic Research Program of Shaanxi Province(2020JQ-950,2022JM-570)+1 种基金Health Research Program of Shaanxi Province(2022D002)Incubation Fund of Shaanxi Provincial People’s Hospital(2018YXQ-07)。
文摘Objective:Clinical and laboratory studies have demonstrated that prelimbic(PrL)and serotonin-4(5-HT4)receptors may have the key role in regulating anxiety.However,the pathophysiology of anxiety in Parkinson’s disease(PD)remains obscure.In this research,the effects of PrL 5-HT4 receptors on anti-anxiety behaviors in hemiparkinsonian rats were investigated.Methods:PD model rats were used as the research subjects,starting with behavioral changes,from the point of view of electrophysiology,the regulatory effect of PrL 5-HT4 receptors on PD-related anxiety and the possible mechanism were explored.Results:Anxiety-like behaviors were induced via MFB lesion in rats.Intra-PrL injection of 5-HT4 receptors agonist RS67333 induced anti-anxiety effects in both sham and PD group.In the sham group,PrL administration of 5-HT4 receptors antagonist SB204070 produce anti-anxiety effects,but in the PD group,the expression of anxiety-like behavior was increased.Compared to the sham group,the effective dose of the behavioral effects of the two drugs in the PD group was obviously higher.Electrophysiological data suggested that PrL administration of RS67333(SB204070)increased(decreased)the firing activities ofγ-aminobutyric acid(GABA)neurons in both groups.Compared with rats in sham group,lesioned rats had a shorter duration of the excitation(inhibition)effects on firing activities of GABA neurons.Conclusion:PrL 5-HT4 receptors regulate anxiety behaviors in PD rats,and its mechanism may be related to the down-regulation of expression or function of PrL 5-HT4 receptors in PD.
文摘目的:从前额叶皮质、海马及下丘脑中5-羟色胺(5-hydroxytryptamine,5-HT)和5-羟色胺受体3(5-hydroxytryptamine receptor3,5-HTR3),5-羟色胺受体4(5-HTR4)角度探讨健脾化湿颗粒改善腹泻型肠易激综合征(diarrhea-predominant irritable bowel syndrome,D-IBS)模型大鼠结肠运动和内脏敏感性的作用机制.方法:采用番泻叶灌胃结合束缚应激法建立D-IBS大鼠模型,应用健脾化湿颗粒进行干预,采用酶联免疫法(ELISA)检测大鼠海马中5-HT含量,采用免疫组织化学法检测前额叶皮质、海马及下丘脑中5-HT、5-HTR3、5-HTR4阳性表达,采用逆转录-聚合酶链反应法检测海马中5-H T R3 m R N A和5-H T R4m RNA的表达水平.结果:与正常组相比,模型组海马中5-HT含量(327.30±22.35 vs 265.33±13.60),前额叶皮质、海马、下丘脑中5-HT阳性表达(0.16±0.02 vs 0.08±0.01,0.19±0.02 vs 0.09±0.01,0.17±0.02 vs 0.08±0.01)明显升高(P<0.01);前额叶皮质、海马、下丘脑中5-HTR3阳性表达(0.29±0.02 vs 0.10±0.01,0.23±0.02 vs 0.09±0.01,0.22±0.02 vs 0.09±0.02)及5-HTR4阳性表达(0.25±0.02 vs0.11±0.01,0.28±0.02 vs 0.10±0.02,0.27±0.02 vs 0.11±0.02)明显升高(P<0.01);海马中5-H T R3 m R N A和5-H T R4 m R N A的表达(0.54±0.01 vs 0.17±0.05,0.73±0.08 vs 0.10±0.02)显著升高(P<0.01).与模型组相比,阳性对照组、中、高剂量组海马中5-H T含量(298.92±12.16、286.29±24.43、279.86±20.05 vs 327.30±22.35)显著下降(P<0.05,P<0.01),中、高剂量组前额叶皮质中5-HT表达(0.12±0.01、0.11±0.01 vs 0.16±0.02)显著下降(P<0.01),阳性对照组、中、高剂量组海马、下丘脑中5-H T表达显著下降(P<0.05,P<0.01);各治疗组前额叶皮质、海马、下丘脑中5-H T R3表达及5-H T R4表达下降显著(P<0.05,P<0.01);各治疗组海马中5-H T R3 m R N A表达及5-H T R4 m R N A表达显著降低(P<0.05,P<0.01).结论:健脾化湿颗粒可能通过下调脑中5-HT、5-HTR3、5-HTR4表达来改善D-IBS模型大鼠结肠运动和内脏敏感性.
