Evidence for a non-classical splanchnic neural control of the feline pylorus.

Electrical stimulation of the divided splanchnic nerves proximal to the celiac ganglion in chloralosed cats induced a dilation of the pylorus in the majority of animals. However, in some cats a pure contractile motor response or a biphasic motor response (contraction followed by dilation) was elicited suggesting that the splanchnic nerves convey excitatory fibres to the pylorus as well. The pyloric and gastric contraction at such stimulation was sensitive to atropine, while the pyloric dilation was not sensitive to cholinergic, adrenergic or ganglionic blocking agents in contrast to the adrenergic gastric dilation. Since the splanchnic nerve and the pyloric wall contain numerous neuropeptides, these substances might be involved in a nonclassical neurotransmission of the splanchnic motor responses of the pylorus.