[The mechanism coupling adrenergic and cholinergic influences on the smooth musculature of the small intestine].
Experimental results, substantiating the idea of a specific mechanism for the activation of small-intestinal smooth muscle by the adrenergic system are summarized. This mechanism is realized via catecholamines affecting excitatory beta-adrenoreceptors located on cholinergic interneurones of the myenteric plexus. The excitatory beta-adrenoreceptors are shown to contribute to the realization of small-intestinal motor responses to acetylcholine, vagal stimulation and 5-hydroxytryptamine, histamine, bradykinin. The data obtained are an evidence of physiological significance of this specific adrenosensitive input of small-intestinal cholinergic neurones. The cholinergic neurones are shown to participate in producing small-intestinal responses to 5-hydroxytryptamine, histamine, bradykinin, the responses being, for this reason, dependent on the level of catecholamines, stimulating excitatory beta-adrenoreceptors. It is suggested that cholinergic neurones of the enteric nervous system are under double adrenergic control: a stimulating effect of catecholamines mediated by excitatory beta-adrenoreceptors is counteracted by an inhibitory effect of alpha-adrenoreceptor activation by sympathetic neuromediator noradrenaline.
Ovsiannikov
V I
VI
Tkachenko
B I
BI
D000818:Animals; D002415:Cats; D007421:Intestine, Small / Q000187:drug effects / Q000502:physiology; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects / Q000502:physiology*; D011941:Receptors, Adrenergic / Q000187:drug effects / Q000502:physiology*; D011950:Receptors, Cholinergic / Q000187:drug effects / Q000502:physiology*
D011941:Receptors, Adrenergic; D011950:Receptors, Cholinergic
Mekhanizm sopriazheniia adrenergicheskikh i kholinergicheskikh vliianiĭ na gladkuiu muskulaturu tonkoĭ kishki.