Dual-targeting AAV9P1-mediated neuronal reprogramming in a mouse model of traumatic brain injury

Traumatic brain injury results in neuronal loss and glial scar formation.Replenishing neurons and eliminating the consequences of glial scar formation are essential for treating traumatic brain injury.Neuronal reprogramming is a promising strategy to convert glial scars to neural tissue.However,previous studies have reported inconsistent results.In this study,an AAV9P1 vector incorporating an astrocyte-targeting P1 peptide and glial fibrillary acidic protein promoter was used to achieve dual-targeting of astrocytes and the glial scar while minimizing off-target effects.The results demonstrate that AAV9P1 provides high selectivity of astrocytes and reactive astrocytes.Moreover,neuronal reprogramming was induced by downregulating the polypyrimidine tract-binding protein 1 gene via systemic administration of AAV9P1 in a mouse model of traumatic brain injury.In summary,this approach provides an improved gene delivery vehicle to study neuronal programming and evidence of its applications for traumatic brain injury.

THE PHARMACOLOGY RESEARCH OF THENORPHINE,A NEW DRUG OF ANALGESIA AND DETOXIFICATION

Thenorphine is a new parrtail agonist of opioid recepter synthesized by our institute of pharmacology and toxicology.There are double effects of agonist and antegonist on opioid recepter. The agonist effect was showed by analgesia. The analgesic properties are stronger efficacy (ED50 1 mg/kg po) ; longer duration (t1/2 9h) and lower dependence (no

Restoration of GABA_(B) receptor expression in cerebral ischemia:a promising novel neuroprotective strategy

Although stroke is a major global health problem, a pharmacological treatment to inhibit ongoing neuronal death in patients is still lacking. In cerebral ischemia, the prevailing form of stroke, severely reduced blood supply by obstruction of blood vessels deprives neurons from oxygen and glucose, eventually leading to metabolic derailment and death of neurons in the affected brain area.

Changes of protein expression during tumorosphere formation of small cell lung cancer circulating tumor cells

Small cell lung cancer(SCLC)is frequently disseminated and has a dismal prognosis with survival times of approximately two years.This cancer responds well to initial chemotherapy but recurs within a short time as a globally chemoresistant tumor.Circulating tumor cells(CTCs)are held responsible for metastasis,the extremely high numbers of these cells in advanced SCLC allowed us to establish several permanent CTC cell lines.These CTCs are distinguished by the spontaneous formation of large spheroids,termed tumorospheres,in regular tissue culture.These contain quiescent and hypoxic cells in their interior and are associated with high chemoresistance compared to single cell cultures.Nine CTC lines were compared for their expression of 84 proteins associated with cancer either as single cells or in the form of tumorospheres in Western blot arrays.With the exception of the UHGc5 line,all other CTC lines express EpCAM and lack a complete EpCAM-negative,vimentin-positive epithelial-mesenchymal transition(EMT)phenotype.Upon formation of tumorospheres the expression of EpCAM,that mediates cell-cell adhesion is markedly upregulated.Proteins such as E-Cadherin,p27 KIP1,Progranulin,BXclx,Galectin-3,and Survivin showed variable changes for the distinct CTC cell lines.In conclusion,EpCAM presents the most critical marker for individual SCLC CTCs and the assembly of highly chemoresistant tumorospheres.

Temporal and Spatial Distribution of SARS-CoV-2 Aerosols in a Large-Scale Fangcang Shelter Hospital in Shanghai,China

The coronavirus disease 2019(COVID-19)pandemic caused by frequently mutating severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has had a worldwide impact.However,detailed data on the potential aerosol transmission of SARS-CoV-2 in real-world and controlled laboratory settings remain sparse.During the COVID-19 pandemic in Shanghai,China in 2022,samples were collected in a Fangcang shelter hospital,a large-scale temporary hospital rapidly built by converting the existing National Exhibition and Convention Center(Shanghai)into a health care facility.Aerosol samples at different sites and intervals around patients and in public areas,surface samples,and pharyngeal swab samples from corresponding patients were included.Samples were tested for SARS-CoV-2 using real-time quantitative polymerase chain reaction(RT-qPCR)assays,followed by sequencing if the cycle threshold(Ct)value was<30.The positivity rate for SARS-CoV-2 in aerosol samples was high in contaminated zones(37.5%,104/277),especially around the bed(41.2%,68/165)and near ventilation inlets(45.2%,14/31).The prevalence of SARS-CoV-2 around the bed,public areas,and air inlets of exhaust vents fluctuated and was closely related to the positivity rate among patients at corresponding sampling sites.Some surface samples of different personal protective equipment from medical staff had high positivity rates.Sixty sequences of joined ORF1ab and spike genes obtained from sixty samples represented two main clusters of Omicron SARS-CoV-2.There was consistency in virus sequences from the same patient and their environment,and the detected virus sequences matched those of virus strains in circulation during the collection periods,which indicated a high likelihood of cross-contamination in the Fangcang shelter hospital.In summary,the results provide a quantitative and real landscape of the aerosol transmission of SARS-CoV-2 and a patient-centered view of contamination in large and enclosed spaces and offer a useful guide for taking targeted measures to avoid nosocomial infections during the management of SARS-CoV-2 or other respiratory virus diseases in a Fangcang shelter hospital.

Induction of apoptosis of human gastric carcinoma SGC-7901 cell line by 5,7-dihydroxy-8-nitrochrysin in vitro

AIM: To investigate the effect of 5, 7-dihydroxy-8- nitrochrysin (NOChR) on apoptosis of human gastric carcinoma SGC-7901 cell line. METHODS: SGC-7901 cells were cultured in vitro and the inhibitory effect of NOChR on proliferation of SGC-7901 cells was measured by using an MTT assay. NOChR-induced apoptosis rate of SGC-7901 cells was detected using flow cytometry (FCM) with PI staining. DNA ladder bands were observed by DNA agarose gel electrophoresis. The influence of NOChR on the proxisome proliferator-activated receptor-γ (PPARγ), Bcl-2 and Bax protein expression of SGC-7901 cells was analyzed by Western blot. RESULTS: MTT assay showed that NOChR markedly inhibited proliferation of SGC-7901 cells in a dose- dependent manner, and when IC50 was 4.14 μmol/L, the potency of NOChR was 10 times than that of lead compound, chrysin (ChR, IC50 was 40.56 μmol/L), and was similar to 5-fluorouracil (5-FU, IC50 was 4.51 μmol/L). FCM with propidium iodide (PI) staining demonstrated that the apoptosis rates of SGC-7901 cells treated with 1.25, 5.00 and 20.00 μmol/L NOChR for 48 h were 9.8% ± 0.2%, 36.8% ± 1.9% and 45.5% ± 3.5%, respectively, and were significantly higher when treated with 5.00 and 20.00 μmol/L NOChR than that with 20.00 μmol/L ChR (12.9% ± 1.5%). DNA agarose gel electrophoresis showed that treatment of SGC-7901 cells with 20.00 μmol/L NOChR for 48 h resulted in typical DNA ladder bands of DNA of SGC-7901 cells, which could be eliminated by treating with 10.00 μmol/L GW9662, a blocker of PPARγ. Western blot analysis revealed that after 24 h of treatment with 20.00 μmol/L NOChR, PPARgamma and Bax protein expression of SGC-7901 cells increased but Bcl-2 expression decreased; however, pre-incubation with 10.00 μmol/L GW9662 could efficiently antagonize and weaken the regulatory effect of 20.00 μmol/L NOChR on Bax and Bcl-2 protein expression of SGC-7901 cells. CONCLUSION: NOChR induces apoptosis of SGC-7901 cell lines by activating PPARγ and decreasing ratio of Bcl-2 to Bax.

Minimally invasive treatment of pancreatic pseudocysts

A pancreatic pseudocyst(PPC) is typically a complication of acute and chronic pancreatitis, trauma or pancreatic duct obstruction. The diagnosis of PPC can be made if an acute fluid collection persists for 4 to 6 wk and is enveloped by a distinct wall.Most PPCs regress spontaneously and require no treatment, whereas some may persist and progress until complications occur. The decision whether to treat a patient who has a PPC, as well as when and with what treatment modalities, is a difficult one. PPCs can be treated with a variety of methods: percutaneous catheter drainage(PCD), endoscopic transpapillary or transmural drainage, laparoscopic surgery, or open pseudocystoenterostomy. The recent trend in the management of symptomatic PPC has moved toward less invasive approaches such as endoscopic- and image-guided PCD. The endoscopic approach is suitable because most PPCs lie adjacent to the stomach. The major advantage of the endoscopic approach is that it creates a permanent pseudocysto-gastric track with no spillage of pancreatic enzymes. However, given the drainage problems, the monitoring, catheter manipulation and the analysis of cystic content are very difficult or impossible to perform endoscopically, unlike in the PCD approach. Several conditions must be met to achieve the complete obliteration of the cyst cavity.Pancreatic duct anatomy is an important factor in the prognosis of the treatment outcome, and the recovery of disrupted pancreatic ducts is the main prognostic factor for successful treatment of PPC, regardless of the treatment method used. In this article, we review and evaluate the minimally invasive approaches in the management of PPCs.

Mitochondrial DNA alterations and mitochondrial dysfunction in the progression of hepatocellular carcinoma

Hepatocellular carcinoma(HCC)is one of the most common malignancies and is ranked third in mortality among cancer-related diseases.Mitochondria are intracellular organelles that are responsible for energy metabolism and cellular homeostasis,and mitochondrial dysfunction has been regarded as a hallmark of cancer.Over the past decades,several types of mitochondrial DNA(mtDNA)alterations have been identified in human cancers,including HCC.However,the role of these mtDNA alterations in cancer progression is unclear.In this review,we summarize the recent findings on the somatic mtDNA alterations identified in HCC and their relationships with the clinicopathological features of HCC.Recent advances in understanding the potential roles of somatic mtDNA alterations in the progression of HCC are also discussed.We suggest that somatic mtDNA mutations and a decrease in the mtDNA copy number are common events in HCC and that a mitochondrial dysfunction-activated signaling cascade may play an important role in the progression of HCC.Elucidation of the retrograde signaling pathways in HCC and the quest for strategies to block some of these pathways will be instrumental for the development of novel treatments for this and other malignancies.

Quantitative Mitochondrial Proteomics Study on Protective Mechanism of Grape Seed Proanthocyanidin Extracts Against Ischemia/Reperfusion Heart Injury in Rat

Cardiac ischemia/reperfusion(I/R) injury is a critical condition,often associated with high morbidity and mortality.The cardioprotective effect of grape seed proanthocyanidin extracts(GSPE) against oxidant injury during I/R has been described in previous studies.However,the underlying molecular mechanisms have not been fully elucidated.This study investigated the effect of GSPE on reperfusion arrhythmias especially ventricular tachycardia(VT) and ventricular fibrillation(VF),the lactic acid accumulation and the ultrastructure of ischemic cardiomyocytes as well as the global changes of mitochondria proteins in in vivo rat heart model against I/R injury.GSPE significantly reduced the incidence of VF and VT,lessened the lactic acid accumulation and attenuated the ultrastructure damage.Twenty differential proteins related to cardiac protection were revealed by isobaric tag for relative and absolute quantitation(iTRAQ) profiling.These proteins were mainly involved in energy metabolism.Besides,monoamine oxidase A(MAOA) was also identified.The differential expression of several proteins was validated by Western blot.Our study offered important information on the mechanism of GSPE treatment in ischemic heart disease.

A Novel Thermosensitive In-situ Gel of Gabexate Mesilate for Treatment of Traumatic Pancreatitis:An Experimental Study

Gabexate mesilate(GM) is a trypsin inhibitor,and mainly used for treatment of various acute pancreatitis,including traumatic pancreatitis(TP),edematous pancreatitis,and acute necrotizing pancreatitis. However,due to the characteristics of pharmacokinetics,the clinical application of GM still needs frequently intravenous administration to keep the blood drug concentration,which is difficult to manage. Specially,when the blood supply of pancreas is directly damaged,intravenous administration is difficult to exert the optimum therapy effect. To address it,a novel thermosensitive in-situ gel of gabexate mesilate(GMTI) was developed,and the optimum formulation of GMTI containing 20.6%(w/w) P-407 and 5.79%(w/w) P188 with different concentrations of GM was used as a gelling solvent. The effective drug concentration on trypsin inhibition was examined after treatment with different concentrations of GMTI in vitro,and GM served as a positive control. The security of GMTI was evaluated by hematoxylin-eosin(HE) staining,and its curative effect on grade Ⅱ pancreas injury was also evaluated by testing amylase(AMS),C-reactive protein(CRP) and trypsinogen activation peptide(TAP),and pathological analysis of the pancreas. The trypsin activity was slightly inhibited at 1.0 and 5.0 mg/m L in GM group and GMTI group,respectively(P<0.05 vs. P-407),and completely inhibited at 10.0 and 20.0 mg/m L(P<0.01 vs. P-407). After local injection of 10 mg/m L GMTI to rat leg muscular tissue,muscle fiber texture was normal,and there were no obvious red blood cells and infiltration of inflammatory cells. Furthermore,the expression of AMS,CRP and TAP was significantly increased in TP group as compared with control group(P<0.01),and significantly decreased in GM group as compared with TP group(P<0.01),and also slightly inhibited after 1.0 and 5.0 mg/m L GMTI treatment as compared with TP group(P<0.05),and significantly inhibited after 10.0 and 20.0 mg/m L GMTI treatment as compared with TP group(P<0.01). HE staining results demonstrated that pancreas cells were uniformly distributed in control group,and they were loosely arranged,partially dissolved,with deeply stained nuclei in TP group. Expectedly,after gradient GMTI treatment,pancreas cells were gradually restored to tight distribution,with slightly stained nuclei. This preliminary study indicated that GMTI could effectively inhibit pancreatic enzymes,and alleviate the severity of trauma-induced pancreatitis,and had a potential drug developing and clinic application value.

Pharmacokinetic and pharmacodynamic analysis of ferulic acidpuerarin-astragaloside in combination with neuroprotective in cerebral ischemia/reperfusion injury in rats

Objective:To investigate the effects of the active ingredients combined therapy on inflammatory factors interleukin 1 beta(IL-1β)and neuropeptide Y(NPY)based on pharmacodynamics in rats.Methods:The animal model was built by transient middle cerebral artery occlusion(MCAO).The method for evaluating the concentrations of the FA-Pr-AI components in rat plasma was established by using HPLC and the expression levels of IL-1βand NPY were determined by ELISA.A new mathematics method of the trend of percentage rate of change(PRC)was used to assess the correlation between pharmacokinetics(PK)and pharmacodynamics(PD).Results:FA-Pr-Al in combination reduced neurological deficits,decreased infarct volume and inhibited the expression levels of IL-1βand NPY(all P<0.05)compared with the model group.FA,Pr and Al all displayed two compartment open models in rats.Clockwise hysteresis loops were obtained by time-concentration-effect curves.IL-1βand NPY level changes in the plasma followed an opposite trend to the plasma concentration tendency after C_(max)was reached.Astragaloside's PRC value was significantly higher than those of FA and puerarin between 120 to 180 min.Conclusions:The pharmacokinetics of FA-PrAl in combination were closely related its pharmacodynamics in treating ischemia/reperfusion injury,and the components of FA-Pr-Al may have a synergistic pharmacological effect.Astragaloside may play a more pronounced role in regulating IL-1βand NPY levels compared with puerarin or FA.

Acute pancreatitis in HIV/AIDS patients:an issue of concern

Pancreatitis is a well-described complication of human immunodeficiency virus(HIV)itself and its comhinalion antiretroviral therapy.Historically,this has been predominantly associated with the usage of nucleoside reverse transcriptase inhibitors such as didanosine and stavndine.but only rarely with the usage of protease inhibitors via the induction of hypertriglyceridemia.Pancreatitis rales in HIV/AIDS population may have been exceedingly high because of the comorbid conditions prevalent in HIV/AIDS patients(e.g.ethanol use and biliary disease),and the use of noncombinalion antiretroviral therapy medications such as pentamidine,corticosteroids,ketocouazole.sulphonamides,metronidazole,isoniazid and opportunistic infections(e.g.cytomegalovirus,crvptosporidiosis.mycobacterial disease).In resource limited settings,where didanosine and stavudine are widely available in cheaper generic lived dose combinations it is likelv that their usage will remain in the first line HIV treatment in common.In such settings management or estimation of a patient's risk of pancreatitis still remains an issue of concern.

Inhibition of α5 GABAA receptors has preventive but not therapeutic effects on isoflurane-induced memory impairment in aged rats

The α5 subunit-containing gamma-amino butyric acid type A receptors(α5 GABAARs) are a distinct subpopulation that are specifically distributed in the mammalian hippocampus and also mediate tonic inhibitory currents in hippocampal neurons. These tonic currents can be enhanced by low-dose isoflurane, which is associated with learning and memory impairment. Inverse agonists of α5 GABAARs, such as L-655,708, are able to reverse the short-term memory deficit caused by low-dose isoflurane in young animals. However, whether these negative allosteric modulators have the same effects on aged rats remains unclear. In the present study, we mainly investigated the effects of L-655,708 on low-dose(1.3%) isoflurane-induced learning and memory impairment in elderly rats. Young(3-month-old) and aged(24-month-old) Wistar rats were randomly assigned to receive L-655,708 0.5 hour before or 23.5 hours after 1.3% isoflurane anesthesia.The Morris Water Maze tests demonstrated that L-655,708 injected before or after anesthesia could reverse the memory deficit in young rats. But in aged rats, application of L-655,708 only before anesthesia showed similar effects. Reverse transcription-polymerase chain reaction showed that low-dose isoflurane decreased the mRNA expression of α5 GABAARs in aging hippocampal neurons but increased that in young animals. These findings indicate that L-655,708 prevented but could not reverse 1.3% isoflurane-induced spatial learning and memory impairment in aged Wistar rats. All experimental procedures and protocols were approved by the Experimental Animal Ethics Committee of Academy of Military Medical Science of China(approval No. NBCDSER-IACUC-2015128) in December 2015.

Propofol effectively inhibits lithium-pilocarpine-induced status epilepticus in rats via downregulation of N-methyl-D-aspartate receptor 2B subunit expression

Status epilepticus was induced via intraperitoneal injection of lithium-pilocarpine.The inhibitory effects of propofol on status epilepticus in rats were judged based on observation of behavior,electroencephalography and 24-hour survival rate.Propofol(12.5-100 mg/kg) improved status epilepticus in a dose-dependent manner,and significantly reduced the number of deaths within 24 hours of lithium-pilocarpine injection.Western blot results showed that,24 hours after induction of status epilepticus,the levels of N-methyl-D-aspartate receptor 2A and 2B subunits were significantly increased in rat cerebral cortex and hippocampus.Propofol at 50 mg/kg significantly suppressed the increase in N-methyl-D-aspartate receptor 2B subunit levels,but not the increase in N-methyl-D-aspartate receptor 2A subunit levels.The results suggest that propofol can effectively inhibit status epilepticus induced by lithium-pilocarpine.This effect may be associated with downregulation of N-methyl-D-aspartate receptor 2B subunit expression after seizures.

The roles of carboxylesterase and CYP isozymes on the in vitro metabolism of T-2 toxin

Background: T-2 toxin poses a great threat to human health because it has the highest toxicity of the currently known trichothecene mycotoxins. To understand the in vivo toxicity and transformation mechanism of T-2 toxin, we investigated the role of two principal phase Ⅰ drug-metabolizing enzymes(cytochrome P450 [CYP450] enzymes) on the metabolism of T-2 toxin, which are crucial to the metabolism of endogenous substances and xenobiotics. We also investigated carboxylesterase, which also plays an important role in the metabolism of toxic substances.Methods: A chemical inhibition method and a recombinant method were employed to investigate the metabolism of the T-2 toxin by the CYP450 enzymes, and a chemical inhibition method was used to study carboxylesterase metabolism. Samples incubated with human liver microsomes were analyzed by high performance liquid chromatography-triple quadrupole mass spectrometry(HPLC- Qq Q MS) after a simple pretreatment.Results: In the presence of a carboxylesterase inhibitor, only 20% T-2 toxin was metabolized. When CYP enzyme inhibitors and a carboxylesterase inhibitor were both present, only 3% of the T-2 toxin was metabolized. The contributions of the CYP450 enzyme family to T-2 toxin metabolism followed the descending order CYP3A4, CYP2E1, CYP1A2, CYP2B6 or CYP2D6 or CYP2C19.Conclusions: Carboxylesterase and CYP450 enzymes are of great importance in T-2 toxin metabolism, in which carboxylesterase is predominant and CYP450 has a subordinate role. CYP3A4 is the principal member of the CYP450 enzyme family responsible for T-2 toxin metabolism. The metabolite produced by carboxylesterase is HT-2, and the metabolite produced by CYP 3A4 is 3'-OH T-2. The different metabolites show different toxicities. Our results will provide useful data concerning the toxic mechanism, the safety evaluation, and the health risk assessment of T-2 toxin.

Heat shock protein inhibitor, quercetin, as a novel adjuvant agent to improve radiofrequency ablation-induced tumor destruction and its molecular mechanism

Background: We investigated the effect of a small molecular inhibitor of heat shock protein(HSP), quercetin, on tumor radiofrequency(RF) ablation, and explored the underlying molecular mechanisms.Methods: In in vivo study, rats with R3230 breast adenocarcinoma were sacrificed 24 h post-treatment and gross coagulation areas were compared, and next, randomized into four treatment arms(control, quercetin alone, RF alone, and combination) for Kaplan-Meier analysis of defined endpoint survival. Then the distribution and expression levels of heat shock protein 70(HSP70), cleaved caspase-3 and heat shock factor 1(HSF1) were analyzed after different treatments. In in vitro study, we used quercetin to promote SKHEP-1(hepatic) and MCF-7(breast) cancer cell apoptosis in heat shock cell model, and si RNA was used to block c-Jun and to explore the role of activating protein-1(AP-1) signaling pathways.Results: We found the effects of quercetin plus RFA resulted in increase on the tumor destruction/endpoint survival(26.5±3.4 d) in vivo, compared with RF alone(17.6±2.5 d) and quercetin alone(15.7±3.1 d). Most importantly, quercetin-induced cancer cell death required the presence of HSF1 in animal model. Furthermore, quercetin directly down-regulated expression of HSF1 in vitro, which our findings have revealed, required the activation of AP-1 signaling pathways by loss-of-function analysis using si RNA mediated targeting of c-Jun.Conclusions: These results indicated a protective role of quercetin in tumor ablation and highlighted a novel mechanism involving HSP70 with HSF1 pathway in thermal ablation of solid tumors.

Construction of a Metagenomic DNA Library of Sponge Symbionts and Screening of Antibacterial Metabolites

为了学习简历，活跃代谢物由导出海绵的未耕作的共生者生产了，海绵 Gelliodes gracilis 的共生者的一个 metagenomic DNA 图书馆被构造。DNA 的平均尺寸在图书馆插入是 20kb。这个图书馆用纸圆盘 assaying 为抗菌素活动被屏蔽。二克隆对小球菌 tetragenus 显示了抗菌剂活动。这二克隆的代谢物通过 HPLC 被分析。结果证明他们的代谢物与主人 E 的那些相当不同。包含向量 pHZ132 的关口 i DH5 α和主人。这研究可以介绍一条新途径给探索简历海绵共生者的活跃代谢物。

Predominant mucosal expression of 5-HT_(4(+h)) receptor splice variants in pig stomach and colon

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.