Neural influence on the action of insulin in the adrenomedullary catecholamine content in the pigeon

Abstract

Insulin-induced (4 IU/100 g b.wt.) changes of adrenomedullary catecholamines (CA) were investigated in unilaterally splanchnic denervated pigeons 0.5, 4, 12, 24, 72, 144 and 216 h after injection. Insulin caused depletion of more norepinephrine (NE) from the denervated glands 0.5 h after treatment. This indicates that the splanchnic nerve prevents early phase of insulin-induced depletion of NE. Accelerated resynthesis of NE exceeding the control value was more in the innervated glands 24 h after administration. Insulin brought about augmented synthesis of epinephrine (E) surpassing the control value in the innervated glands 72 h after treatment. The findings point out that the splanchnic nerve stimulates resynthesis of NE and synthesis of E induced by insulin.