title: Characterization of the effect of penehyclidine hydrochloride on muscarinic receptor subtypes mediating the contraction of guinea-pig isolated gastrointestinal smooth muscle.
abstract: OBJECTIVE
  The aim was to characterize the effect of penehyclidine hydrochloride, which mediates the relaxation of guinea-pig isolated gastrointestinal smooth muscle, on muscarinic receptor subtypes.
  
  
  METHODS
  Radioimmune assay was used to determine cAMP levels in isolated guinea-pig gastrointestinal smooth muscle to compare the selective effects of penehyclidine hydrochloride on muscarinic receptor subtypes.
  
  
  RESULTS
  The results indicated that the relaxing effect of penehyclidine hydrochloride on isolated gastrointestinal smooth muscle contraction induced by acetylcholine was stronger than that of atropine (based on PA2 values). In the radioimmune assay, penehyclidine hydrochloride increased the cAMP content in isolated guinea-pig stomach smooth muscle and decreased the cAMP content in isolated guinea-pig intestinal smooth muscle, but the difference was not statistically significant at a dose of 10 mumol/l.
  
  
  CONCLUSIONS
  The results suggest that penehyclidine hydrochloride has little or no effect on M2 receptor subtypes in guinea-pig gastrointestinal smooth muscle.
authors: Department of Pharmacy, Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital, Chengdu, China. xht927@163.com
authors: Hong-Tao
authors: HT
authors: Xiao
authors: Zhi
authors: Z
authors: Liao
authors: Xian-Min
authors: XM
authors: Meng
authors: Xiao-Yan
authors: XY
authors: Yan
authors: Shu-Jie
authors: SJ
authors: Chen
authors: Zheng-Ji
authors: ZJ
authors: Mo
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D000242:Cyclic AMP / Q000096:biosynthesis; D004305:Dose-Response Relationship, Drug; D005260:Female; D041981:Gastrointestinal Tract / Q000187:drug effects* / Q000502:physiology; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009126:Muscle Relaxation / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects* / Q000502:physiology; D011812:Quinuclidines / Q000494:pharmacology*; D011869:Radioligand Assay; D043585:Receptor, Muscarinic M2 / Q000037:antagonists & inhibitors / Q000502:physiology*; D043587:Receptor, Muscarinic M3 / Q000037:antagonists & inhibitors / Q000502:physiology*
chemical_list: D011812:Quinuclidines; D043585:Receptor, Muscarinic M2; D043587:Receptor, Muscarinic M3; C486140:penehyclidine; D001285:Atropine; D000242:Cyclic AMP; D000109:Acetylcholine