Theophylline-sensitive modulation of non-cholinergic excitatory neurotransmission in the guinea-pig ileum.
Atropine-resistant longitudinal contractions of the guinea-pig ileum due to field stimulation were greatly augmented by theophylline (150 microM). Adenosine exerted an opposite effect. Theophylline did not potentiate contractions evoked by exogenous substance P. It is suggested that a theophylline-sensitive inhibitory mechanism (possibly mediated by adenosine or a related substance) controls transmitter release from enteric non-cholinergic excitatory neurones.
D000241:Adenosine / Q000494:pharmacology; D000818:Animals; D001285:Atropine / Q000494:pharmacology; D001341:Autonomic Nervous System / Q000502:physiology*; D004558:Electric Stimulation; D006168:Guinea Pigs; D007082:Ileum / Q000294:innervation; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects; D009435:Synaptic Transmission / Q000187:drug effects*; D013806:Theophylline / Q000494:pharmacology*
D001285:Atropine; D013806:Theophylline; D000241:Adenosine