On the Influence of Pilocarpine upon the Epinephrine Output from the Suprarenal Glands in Dogs and Cats

Abstract

Pilocarpine was in most cases intravenously given into cats and dogs, provided with the cava pocket under narcosis. Epinephrine was determined by means of the cat paradoxical pupil reaction.
Subcutaneous 1 mgrm. pilocarpine per kilo was proved to have sometimes an accelerating effect in the dog. This dose apparently checks with that in the non-anaesthetized dog.
Intravenous 1-2 mgrms. pilocarpine was proved to accelerate the epinephrine output in the dogs anaesthetized, but its magnitude was small and the period when it became manifest was much earlier than in the experiments with the non-anaesthetized dogs.
Experiments on cats anaesthetized show nearly similar effective doses, that is, 1 mgrm. pilocarpine per kilo was not effective, where-as 2-5 mgrms. was usually capable of accelerating the output.
Apparently peculiar is the fact that in the cage pocket experiment which is carried out under anaesthesia and laparotomy, the epinephrine output rate underwent a decided reduction when a small amount of pilocarpine was given. If the amount be intermediate, a transitory reduction is followed by an appearance of an accelerated liberation of epinephrine. No reduction was discovered in the dogs, non-anaes-thetized (F. Watanabe).
Briefly said: Accelerating action of pilocarpine upon the epine-phrine discharge from the suprarenals appears in a somewhat small degree if given to the animal under anaesthesia, and it becomes manifest much earlier than in the non-anaesthetized animal, and continues for a much shorter time.
On a small dose of pilocarpine the epinephrine discharge rate, estimated by means of the cava pocket method, becomes definitely smaller than the initial rate, which is much larger than the basal rate in the non-anaesthetized, non-laparotomized animal.