Adrenergic control of the anuran cutaneous hydroosmotic response.

Adrenergic effectors were shown to play a major role in increasing cutaneous water uptake (the hydroosmotic response) in dehydrated anurans. A beta-adrenergic antagonist, propranolol, blocked 61% of the cutaneous response to dehydration and 67% of the response elicited by salt loading in the toad Bufo cognatus. A beta-adrenergic agonist, isoproterenol, elicited a response in normally hydrated animals equal to the propranolol-sensitive portion of the cutaneous hydroosmotic response of dehydrated animals. The isoproterenol-induced cutaneous water balance response in hydrated animals greatly exceeded the response induced by arginine vasotocin, the endogenous antidiuretic hormone.