Abstract
Plasma of Elaphe quadrivirgata was incubated in vitro under various conditions, and angiotensin I produced was estimated. Renin-like activity deduced from the amount of angiotensin I formation was higher at 37° than at 20° or 4°. The enzyme activity in the snake was higher at pH 4.5 than at 5.0, while that in mammals is highest at pH 5.0. The activity was markedly reduced in winter during hibernation, compared with that in summer. Among the organs renin-like activity was found only in the kidney. Thus, the renin-like active enzyme present in the plasma of Elaphe quadrivirgata may originate mainly from the kidney. The enzyme activity depends on the incubation conditions, and the season of sample collection.
