Nervous control of pancreatic endocrine secretion in pigs. II. The effect of pharmacological blocking agents on the response to vagal stimulation.

The glucose dependent glucagon and insulin responses to electrical vagal stimulation in anesthetized splanchnicotomized young pigs were studied after administration of various pharmacological blocking agents. Hexamethonium completely abolished the responses, regardless of the glucose level. Atropine was without effect on the glucagon as well as the insulin response, regardless of stimulation frequency, glucose level, or dose of atropine. Neither propranolol nor a combination of propranolol and phenoxybenzamine inhibited the response. Our findings indicate that neither adrenergic fibres nor fibres impinging on muscarinic cholinergic receptors are involved in the pancreatic endocrine response to vagal stimulation.