A comparison of the excitatory and inhibitory effects of non-adrenergic, non-cholinergic nerve stimulation and exogenously applied ATP on a variety of smooth muscle preparations from different vertebrate species.
1. The responses to non-adrenergic, non-cholinergic nerve stimulation have been compared with those to exogenously applied ATP on seventeen different tissues from a number of vertebrate classes.2. Stimulation of all the mammalian gut preparations studied (with the exception of the guinea-pig ileum) after blockade of the effects of adrenergic and cholinergic nerve stimulation by guanethidine (3.5 muM) and hyoscine (1.3 muM) caused inhibition; exogenously applied ATP mimicked this inhibitory response.3. Stimulation of the guinea-pig ileum in the presence of hyoscine and guanethidine, usually caused a diphasic response, relaxation followed by contraction; exogenously applied ATP mimicked this response, in contrast to acetylcholine and noradrenaline which caused excitation and relaxation respectively.4. Stimulation of preparations of lower vertebrate gut and guinea-pig bladder in the presence of hyoscine and guanethidine caused contraction; exogenously applied ATP mimicked this contractile response.5. In each preparation the time course of the response to ATP was similar or identical to the response to non-adrenergic, non-cholinergic nerve stimulation.6. The results are consistent with the hypothesis that a purine nucleotide may be the transmitter substance released from non-adrenergic, non-cholinergic nerves supplying smooth muscle preparations from a number of vertebrate classes.
D000109:Acetylcholine / Q000494:pharmacology; D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000818:Animals; D002024:Bufo marinus; D003106:Colon / Q000502:physiology; D004386:Duodenum / Q000502:physiology; D004558:Electric Stimulation; D005399:Fishes; D006145:Guanethidine / Q000494:pharmacology; D006168:Guinea Pigs; D006801:Humans; D007082:Ileum / Q000502:physiology; D008116:Lizards; D051379:Mice; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000502:physiology*; D009638:Norepinephrine / Q000494:pharmacology; D051381:Rats; D012007:Rectum / Q000502:physiology; D012601:Scopolamine / Q000494:pharmacology; D013270:Stomach / Q000502:physiology; D001743:Urinary Bladder / Q000502:physiology
D000255:Adenosine Triphosphate; D012601:Scopolamine; D000109:Acetylcholine; D009638:Norepinephrine; D006145:Guanethidine