LIVER CATALASE ACTIVITY IN PARABIOTIC RATS, ONE OF WHICH IS THYROIDECTOMIZED

Abstract

THE fact that liver catalase activity is reduced in tumor-bearing animals has led to many investigations, but the meaning of this change has not yet been elucidated (Greenstein 1954). Because it seemed important to know more about what factors operate in regulating catalase activity in non-tumor-bearing animals, we have investigated further the role of endocrine factors.

Liver catalase activity is lowered by adrenalectomy and by castration of male mice (Adams 1952). On the other hand, an increase in catalase activity of the liver has been reported after hypophysectomy (Gaebler and Mathies 1951). In our previous experiments we found an increase in liver catalase activity after thyroidectomy in rats and after thiouracil administration in rats and mice (Zeckwer, Berwick, Lucke 1954).

The present experiments were carried out to see if the method of parabiosis would give a clue as to the mechanism by which hypothyroidism results in an increase in catalase activity.