Action of Adrenalin on the Metabolism of Peripheral Tissues.

Abstract

It has been found impossible to affect the carbon dioxide or total acid production of excised frog muscles by placing them in adrenalin solutions. 1 The absence of a calorigenic effect 2 under such unphysiological conditions was not surprising; and more recent work has indicated that the absence of the viscera 3 and particularly of the liver 4 may have been as responsible for the negative result as the lack of proper circulation or other abnormal conditions to which the muscles themselves were immediately exposed.

It is not known in what manner the viscera cooperate in the calorigenic action of adrenalin; whether by serving as the locus of its action, or by keeping the peripheral tissues in the proper physiological condition to respond to the adrenalin itself. The following experiments were undertaken to determine some of the effects that might be produced in one of the hind legs of an anesthetized cat upon the addition of a known amount of adrenalin, directly to its arterial blood supply.

All experiments were done on cats under chloralose anesthesia. The animal was always prepared so that simultaneous samples could be taken of the arterial blood going to and venous blood coming from the left hind leg. At the time of collection of the venous sample the rate of flow was also determined in a manner somewhat similar to that described by Himwich and Castle. 5 The usual precautions were taken to prevent alteration in the gas content of the blood; and this was determined by the manometric method of Van Slyke and Neill, using 0.2 cc. samples in duplicate.

In large cats that could stand the additional loss of blood, 2 normal sets of samples, 10 or 15 minutes apart, were taken before the adrenalin injection; these served to establish the average spontaneous variation to be expected under the conditions of these experiments. In the remaining experiments the adrenalin was injected immediately after taking a single normal pair of samples.