THE RELATIONSHIP OF SERUM PHOSPHATASES TO SEX HORMONES

Abstract
Castration produces a fall in serum inorganic phosphorus values in adult male rats but not in adult female rats. The alterations of phosphorus levels that occur following castration in male rats and after the injection of some hormones into normal and castrated rats of both sexes may be accounted for by corresponding alterations in metabolic requirements. Neither castration nor hormone injection produces any significant change in serum acid phosphatase activity in male or in female rats. A fall of about 30% to levels approaching values for normal female rats is found in serum alkaline phosphatase of castrated male rats in about eight weeks. There is no change in the enzyme values in castrated females. In those instances where injections of a sex hormone into castrated or normal rats produce alterations in alkaline serum phosphatase values such changes may be accounted for on the basis of altered food intake. The sole exception to this finding is the very marked decrease in the activity of the enzyme produced by progesterone after oestrogen in normal male rats.