Serotonin 5-HT2A receptors are playing an important role in the pathophysiology of aggressive behaviors and in the control of immune function. In the present study, we analyzed the effects of activation and blockade o...Serotonin 5-HT2A receptors are playing an important role in the pathophysiology of aggressive behaviors and in the control of immune function. In the present study, we analyzed the effects of activation and blockade of 5-HT2A receptors with selective ligands on the immune response formation in animals with aggressive behaviors induced by genetic factors (rats selected for the increased aggressiveness toward human) or by chronic social stress (mice of the CBA/Lac strain engaged in 10 days of social confrontations). Activation of 5-HT2A receptors with DOI at 1.0 mg/kg reduced the immune response level both in aggressive rats and mice compared to the corresponding vehicle-treated groups, while DOI administration did not alter the immune reaction in nonaggressive animals. The blockade of 5-HT2A receptors with ketanserin at 1.0 mg/kg resulted in immunostimulation both in mice of the CBA strain not subjected to social stress (the controls) and in nonaggressive rats selected for elimination of aggressiveness. On the other hand, its administration to CBA mice demonstrating offensive aggression enhanced the immune reaction, while the same dose of ketanserin did not modify the immune response level in rats with genetic predisposition to the increased defensive aggression. Thus, our data suggest that the role of 5-HT2A receptors in immunomodulation depends on the specific type of aggression that may be taking into account in the treatment of some neuropsychiatric disorders with the antipsychotic drugs and antidepressants targeting 5-HT2A receptors.展开更多
Background： To evaluate whether serotonin （5-HT）, 5-HT2A receptor （5-HT2AR）, and 5-HT transporter （serotonin transporter [SERT]） are associated with different disease states of depression, myocardial infarction...Background： To evaluate whether serotonin （5-HT）, 5-HT2A receptor （5-HT2AR）, and 5-HT transporter （serotonin transporter [SERT]） are associated with different disease states of depression, myocardial infarction （MI） and MI co-exist with depression in Sprague-Dawley rats. Methods： After established the animal model of four groups include control, depression, MI and MI with depression, we measured 5-HT, 5-HT2AR and SERT from serum and platelet lysate.Results： The serum concentration of 5-HT in depression rats decreased significantly compared with the control group （303.25 ± 9.99 vs. 352.98 ±13.73; P =0.000）, while that in MI group increased （381.78 ±14.17 vs. 352.98 ±13.73; P = 0.000）. However, the depression ＋ MI group had no change compared with control group （360.62 ±11.40 vs. 352.98 ±13.73; P = 0.036）. The changes of the platelet concentration of 5-HT in the depression, MI, and depression ＋ MI group were different from that of serum. The levels of 5-HT in above three groups were lower than that in the control group （380.40 ± 17.90, 387.75 ±22.28,246.40 ±18.99 vs. 500.29 ±20.91 ; P = 0.000）. The platelet lysate concentration of 5-HT2AR increased in depression group, MI group, and depression ＋ MI group compared with the control group （370.75 ±14.75,393.47 ±15.73,446.66 ±18.86 vs. 273.66 ±16.90; P= 0.000）. The serum and platelet concentration of SERT in the depression group, MI group and depression ＋ MI group were all increased compared with the control group （527.51 ±28.32, 602.02 ±23.32, 734.76 ±29.59 vs. 490.56 ±16.90; P 0,047, P = 0.000, P = 0.000 in each and 906.38 ±51.84, 897.33 ±60.34, 1030.17 ±58.73 vs. 708.62 ±51.15; P = 0.000 in each）. Conclusions： The concentration of 5-HT2AR in platelet lysate and SERT in serum and platelet may be involved in the pathway of MI with depression. Further studies should examine whether elevated 5-HT2AR and SERT may contribute to the biomarker in MI patients with depression.展开更多
It has been postulated that the persistent short intravaginal ejaculation latency time （IELT） of men with lifelong premature ejaculation （LPE） is related to 5-hydroxytryptamine （HT）2c receptor functioning. The a...It has been postulated that the persistent short intravaginal ejaculation latency time （IELT） of men with lifelong premature ejaculation （LPE） is related to 5-hydroxytryptamine （HT）2c receptor functioning. The aim of this study was to investigate the relationship of Cys23Ser 5-HT2c receptor gene polymorphism and the duration of IELT in men with LPE. Therefore, a prospective study was conducted in 64 Dutch Caucasian men with LPE. Baseline IELT during coitus was assessed by stopwatch over a 1-month period. All men were genotyped for Cys23Ser 5-HT2c receptor gene polymorphism. Allele frequencies and genotypes of Cys and Ser variants of 5-HT2c receptor gene polymorphism were determined. Association between Cys/Cys and Ser/Ser genotypes and the natural logarithm of the IELT in men with LPE were.investigated. As a result, the geometric mean, median and natural mean IELT were 25.2, 27.0, 33.9s, respectively. Of all men, 20.0%, 10.8%, 23.1% and 41.5% ejaculated within 10, 10-20, 20-30 and 30-60s after vaginal penetration. Of the 64 men, the Cys/Cys and Ser/Ser genotype frequency for the Cys23Ser polymorphism of the 5-HT2c receptor gene was 81% and 19%, respectively. The geometric mean IELT of the wildtypes （Cys/Cys） is significantly lower （22.6s; 95% CI 18.3-27.8s） than in male homozygous mutants （Ser/Ser） （40.4s; 95% CI 20.3-80.4s） （P = 0.03）. It is concluded that Cys23Ser 5-HT2c receptor gene polymorphism is associated with the IELT in men with LPE. Men with Cys/Cys genotype have shorter IELTs than men with Ser/Ser genotypes.展开更多
OBJECTIVE Prepulse inhibition(PPI)of the acoustic startle response provides a measure of sensorimotor gating system mecha⁃nisms,which is known to be impaired in schizo⁃phrenia patients.We assessed the effects of the 5...OBJECTIVE Prepulse inhibition(PPI)of the acoustic startle response provides a measure of sensorimotor gating system mecha⁃nisms,which is known to be impaired in schizo⁃phrenia patients.We assessed the effects of the 5-HT2A/2C receptor agonist(±)2,5-dimethoxy-4-methylamphetamine(DOM),the NMDA receptor antagonist ketamine,the dopamine receptor ago⁃nist methamphetamine(Meth)on PPI and the startle magnitude in SD rats.METHODS AND RESULTS Systemic administration of the three compounds all dose-dependently reduced PPI.However,as far as startle magnitude,only DOM at the doses of 3 mg·kg-1 reduced that,while both ketamine and Meth did not change the startle magnitudes.Furthermore,to determine whether 5-HT2A receptor mediate this effect,the non-spe⁃cific 5-HT2 receptor antagonist cyproheptadine,specific 5-HT2A receptor antagonist ketanserin and specific 5-HT2C receptor antagonist SB242084 were tested.Cyproheptadine,ketan⁃serin and SB242084 did not alter startle ampli⁃tude by themselves in SD rats and only ketanserin slightly increased PPI at higher dose(3 mg·kg-1).PPI impairment induced by DOM was restored by pretreatment of cyproheptadine(1 mg·kg-1)and ketanserin(1 mg·kg-1),while not by pretreat⁃ment of SB242084(1 mg·kg-1).Damage of PPI induced by ketamine and Meth was not reversed by cyproheptadine(1 and 5 mg·kg-1).CONCLU⁃SION The receptor mechanisms underlying the disruption of PPI caused by DOM,ketamine and Meth were different from each other,at least 5-HT2A receptor was not the junction receptor for which the three chemicals acted.展开更多
Hepatocytes were isolated from livers of adult male SpragueDawley rats and cultured in Williams'E Medium with 3 H thymidine. The effect of 5hydroxytryptamine (5HT) was investigated through adding various concentra...Hepatocytes were isolated from livers of adult male SpragueDawley rats and cultured in Williams'E Medium with 3 H thymidine. The effect of 5hydroxytryptamine (5HT) was investigated through adding various concentrations (10-810-3 mol/L) of 5HT to the hepatocyte cultures in the presence or absence of epidermal growth factor (EGF) and insulin. The involvement of 5HT2 receptor was examined by adding a 5HT2 receptor antagonist, ketanserin (10-6 mol/L), to some of the cultures containing 5HT. The increment of DNA synthesis was measured by 3 H thymidine incorporation. The results showed that 5HT2 (10-6 mol/L) significantly (P<005) increased the amount of DNA synthesis induced by EGF and insulin in the cultured adult rat hepaptocytes. The effect of 5HT in enhancing DNA synthesis began to appear at a concentration between 10-7 and 10-6 mol/L and reached maximum at concentrations of 10-4 mol/L. The enhancement of DNA synthesis by 5HT was significantly (P<005) antagonized by ketanserin, suggesting that this effect of 5HT was mediated by 5HT2 receptor subtype.展开更多
Deficits in serotonin (5-hydroxytryptamine, 5-HT) neurotransmission are implicated in abnormal emotional behaviors such as aggression, anxiety, and depression. However, the specific 5-HT receptor mechanisms involved a...Deficits in serotonin (5-hydroxytryptamine, 5-HT) neurotransmission are implicated in abnormal emotional behaviors such as aggression, anxiety, and depression. However, the specific 5-HT receptor mechanisms involved are not well understood. The role of 5-HT2 receptors in fear potentiated startle, (FPS) was examined in rats chronically treated with pchlorophenylalanine (PCPA) to reduce brain 5-HT. PCPA-treated rats show an enhanced magnitude of FPS. Systemic administration of the 5-HT2 receptor agonist (±)-2,5-Dimethoxy-4-iodoamphetamine hydrochloride (DOI) reduced FPS in both PCPA-treated and saline (SAL)-treated control animals, normalizing the exaggerated fear response in PCPA-treated rats. In both SAL- and PCPA-treated animals, the DOI-induced reduction of learned fear was reversed by the 5-HT2 antagonist ketanserin, but not by the 5-HT2B/2C antagonist SB 206553. Together, these findings suggest 5-HT2A receptors are critical regulators of learned fear, and that 5-HT2A receptors may be an important pharmacological target to normalize exaggerated learned fear resulting from chronic 5-HT-ergic disruption.展开更多
文摘Serotonin 5-HT2A receptors are playing an important role in the pathophysiology of aggressive behaviors and in the control of immune function. In the present study, we analyzed the effects of activation and blockade of 5-HT2A receptors with selective ligands on the immune response formation in animals with aggressive behaviors induced by genetic factors (rats selected for the increased aggressiveness toward human) or by chronic social stress (mice of the CBA/Lac strain engaged in 10 days of social confrontations). Activation of 5-HT2A receptors with DOI at 1.0 mg/kg reduced the immune response level both in aggressive rats and mice compared to the corresponding vehicle-treated groups, while DOI administration did not alter the immune reaction in nonaggressive animals. The blockade of 5-HT2A receptors with ketanserin at 1.0 mg/kg resulted in immunostimulation both in mice of the CBA strain not subjected to social stress (the controls) and in nonaggressive rats selected for elimination of aggressiveness. On the other hand, its administration to CBA mice demonstrating offensive aggression enhanced the immune reaction, while the same dose of ketanserin did not modify the immune response level in rats with genetic predisposition to the increased defensive aggression. Thus, our data suggest that the role of 5-HT2A receptors in immunomodulation depends on the specific type of aggression that may be taking into account in the treatment of some neuropsychiatric disorders with the antipsychotic drugs and antidepressants targeting 5-HT2A receptors.
文摘Background： To evaluate whether serotonin （5-HT）, 5-HT2A receptor （5-HT2AR）, and 5-HT transporter （serotonin transporter [SERT]） are associated with different disease states of depression, myocardial infarction （MI） and MI co-exist with depression in Sprague-Dawley rats. Methods： After established the animal model of four groups include control, depression, MI and MI with depression, we measured 5-HT, 5-HT2AR and SERT from serum and platelet lysate.Results： The serum concentration of 5-HT in depression rats decreased significantly compared with the control group （303.25 ± 9.99 vs. 352.98 ±13.73; P =0.000）, while that in MI group increased （381.78 ±14.17 vs. 352.98 ±13.73; P = 0.000）. However, the depression ＋ MI group had no change compared with control group （360.62 ±11.40 vs. 352.98 ±13.73; P = 0.036）. The changes of the platelet concentration of 5-HT in the depression, MI, and depression ＋ MI group were different from that of serum. The levels of 5-HT in above three groups were lower than that in the control group （380.40 ± 17.90, 387.75 ±22.28,246.40 ±18.99 vs. 500.29 ±20.91 ; P = 0.000）. The platelet lysate concentration of 5-HT2AR increased in depression group, MI group, and depression ＋ MI group compared with the control group （370.75 ±14.75,393.47 ±15.73,446.66 ±18.86 vs. 273.66 ±16.90; P= 0.000）. The serum and platelet concentration of SERT in the depression group, MI group and depression ＋ MI group were all increased compared with the control group （527.51 ±28.32, 602.02 ±23.32, 734.76 ±29.59 vs. 490.56 ±16.90; P 0,047, P = 0.000, P = 0.000 in each and 906.38 ±51.84, 897.33 ±60.34, 1030.17 ±58.73 vs. 708.62 ±51.15; P = 0.000 in each）. Conclusions： The concentration of 5-HT2AR in platelet lysate and SERT in serum and platelet may be involved in the pathway of MI with depression. Further studies should examine whether elevated 5-HT2AR and SERT may contribute to the biomarker in MI patients with depression.
文摘It has been postulated that the persistent short intravaginal ejaculation latency time （IELT） of men with lifelong premature ejaculation （LPE） is related to 5-hydroxytryptamine （HT）2c receptor functioning. The aim of this study was to investigate the relationship of Cys23Ser 5-HT2c receptor gene polymorphism and the duration of IELT in men with LPE. Therefore, a prospective study was conducted in 64 Dutch Caucasian men with LPE. Baseline IELT during coitus was assessed by stopwatch over a 1-month period. All men were genotyped for Cys23Ser 5-HT2c receptor gene polymorphism. Allele frequencies and genotypes of Cys and Ser variants of 5-HT2c receptor gene polymorphism were determined. Association between Cys/Cys and Ser/Ser genotypes and the natural logarithm of the IELT in men with LPE were.investigated. As a result, the geometric mean, median and natural mean IELT were 25.2, 27.0, 33.9s, respectively. Of all men, 20.0%, 10.8%, 23.1% and 41.5% ejaculated within 10, 10-20, 20-30 and 30-60s after vaginal penetration. Of the 64 men, the Cys/Cys and Ser/Ser genotype frequency for the Cys23Ser polymorphism of the 5-HT2c receptor gene was 81% and 19%, respectively. The geometric mean IELT of the wildtypes （Cys/Cys） is significantly lower （22.6s; 95% CI 18.3-27.8s） than in male homozygous mutants （Ser/Ser） （40.4s; 95% CI 20.3-80.4s） （P = 0.03）. It is concluded that Cys23Ser 5-HT2c receptor gene polymorphism is associated with the IELT in men with LPE. Men with Cys/Cys genotype have shorter IELTs than men with Ser/Ser genotypes.
文摘OBJECTIVE Prepulse inhibition(PPI)of the acoustic startle response provides a measure of sensorimotor gating system mecha⁃nisms,which is known to be impaired in schizo⁃phrenia patients.We assessed the effects of the 5-HT2A/2C receptor agonist(±)2,5-dimethoxy-4-methylamphetamine(DOM),the NMDA receptor antagonist ketamine,the dopamine receptor ago⁃nist methamphetamine(Meth)on PPI and the startle magnitude in SD rats.METHODS AND RESULTS Systemic administration of the three compounds all dose-dependently reduced PPI.However,as far as startle magnitude,only DOM at the doses of 3 mg·kg-1 reduced that,while both ketamine and Meth did not change the startle magnitudes.Furthermore,to determine whether 5-HT2A receptor mediate this effect,the non-spe⁃cific 5-HT2 receptor antagonist cyproheptadine,specific 5-HT2A receptor antagonist ketanserin and specific 5-HT2C receptor antagonist SB242084 were tested.Cyproheptadine,ketan⁃serin and SB242084 did not alter startle ampli⁃tude by themselves in SD rats and only ketanserin slightly increased PPI at higher dose(3 mg·kg-1).PPI impairment induced by DOM was restored by pretreatment of cyproheptadine(1 mg·kg-1)and ketanserin(1 mg·kg-1),while not by pretreat⁃ment of SB242084(1 mg·kg-1).Damage of PPI induced by ketamine and Meth was not reversed by cyproheptadine(1 and 5 mg·kg-1).CONCLU⁃SION The receptor mechanisms underlying the disruption of PPI caused by DOM,ketamine and Meth were different from each other,at least 5-HT2A receptor was not the junction receptor for which the three chemicals acted.
文摘Hepatocytes were isolated from livers of adult male SpragueDawley rats and cultured in Williams'E Medium with 3 H thymidine. The effect of 5hydroxytryptamine (5HT) was investigated through adding various concentrations (10-810-3 mol/L) of 5HT to the hepatocyte cultures in the presence or absence of epidermal growth factor (EGF) and insulin. The involvement of 5HT2 receptor was examined by adding a 5HT2 receptor antagonist, ketanserin (10-6 mol/L), to some of the cultures containing 5HT. The increment of DNA synthesis was measured by 3 H thymidine incorporation. The results showed that 5HT2 (10-6 mol/L) significantly (P<005) increased the amount of DNA synthesis induced by EGF and insulin in the cultured adult rat hepaptocytes. The effect of 5HT in enhancing DNA synthesis began to appear at a concentration between 10-7 and 10-6 mol/L and reached maximum at concentrations of 10-4 mol/L. The enhancement of DNA synthesis by 5HT was significantly (P<005) antagonized by ketanserin, suggesting that this effect of 5HT was mediated by 5HT2 receptor subtype.
文摘Deficits in serotonin (5-hydroxytryptamine, 5-HT) neurotransmission are implicated in abnormal emotional behaviors such as aggression, anxiety, and depression. However, the specific 5-HT receptor mechanisms involved are not well understood. The role of 5-HT2 receptors in fear potentiated startle, (FPS) was examined in rats chronically treated with pchlorophenylalanine (PCPA) to reduce brain 5-HT. PCPA-treated rats show an enhanced magnitude of FPS. Systemic administration of the 5-HT2 receptor agonist (±)-2,5-Dimethoxy-4-iodoamphetamine hydrochloride (DOI) reduced FPS in both PCPA-treated and saline (SAL)-treated control animals, normalizing the exaggerated fear response in PCPA-treated rats. In both SAL- and PCPA-treated animals, the DOI-induced reduction of learned fear was reversed by the 5-HT2 antagonist ketanserin, but not by the 5-HT2B/2C antagonist SB 206553. Together, these findings suggest 5-HT2A receptors are critical regulators of learned fear, and that 5-HT2A receptors may be an important pharmacological target to normalize exaggerated learned fear resulting from chronic 5-HT-ergic disruption.
