Studies on Manganese Deficiency in the Rat

Abstract

Summary Pronounced manganese deficiency in the rat has been produced by use of rats weaned without access to manganese. This deficiency resulted in definitely impaired growth in the male and the female rat. In the manganese-deficient female rat estrous cycles were irregular or absent, and there was a marked delay in the opening of the vaginal orifice. A manganese deficiency in the male rat caused testicular degeneration and complete sterility due to lack of spermatozoa production. Both male and female manganese-deficient rats were unable to reproduce. No histological abnormalities were detected in the adrenal, kidney, pituitary, and thyroid of the manganese-deficient rat. The deficiency did not result in reduced ascorbic acid content of tissues, nor did ascorbic acid stimulate the growth of the manganese-deficient rat. Synthesis of ascorbic acid from mannose by rat liver and other tissues in vitro could not be obtained with or without added manganese. A reduced arginase concentration in the liver of the manganese-deficient rat was found. There were no essential differences in the activity of the intestinal dipeptidases studied.