title: Desensitization of the guinea-pig urinary bladder by the enantiomers of adenylyl 5'-(beta, gamma-methylene)-diphosphonate and by substance P.
abstract: Adenosine 5'-triphosphate (ATP), substance P (SP) and non-cholinergic nerve stimulation contracted the guinea-pig urinary bladder. SP and two poorly-degradable analogues of ATP, the enantiomers of adenylyl 5'-(beta, gamma-methylene)-diphosphonate (AMP-PCP and L-AMP-PCP), were used to desensitize the guinea-pig bladder. Desensitization of the bladder by AMP-PCP (50 microM) or by L-AMP-PCP (50 microM) abolished the responses to ATP, and inhibited the responses to non-cholinergic nerve stimulation and to SP. The responses to histamine were unaffected. Desensitization by SP (1 microM) inhibited the responses to SP itself, but not the responses to ATP, L-AMP-PCP or non-cholinergic nerve stimulation. These results suggest that SP may act partly by releasing ATP, and support the suggestion that ATP rather than SP is the non-cholinergic stimulatory transmitter.
mesh_terms: D000255:Adenosine Triphosphate / Q000031:analogs & derivatives* / Q000494:pharmacology; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D004347:Drug Interactions; D004558:Electric Stimulation; D006168:Guinea Pigs; D006632:Histamine / Q000378:metabolism; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects*; D018377:Neurotransmitter Agents / Q000378:metabolism; D013237:Stereoisomerism; D013373:Substance P / Q000494:pharmacology*; D001743:Urinary Bladder / Q000187:drug effects
chemical_list: D018377:Neurotransmitter Agents; D013373:Substance P; C005147:5'-adenylyl (beta,gamma-methylene)diphosphonate; D001285:Atropine; D006632:Histamine; D000255:Adenosine Triphosphate; C002630:alpha,beta-methyleneadenosine 5'-triphosphate