CONCENTRATION OF GONADOTROPHINS IN THE PLASMA AND TESTICULAR RESPONSIVENESS TO GONADOTROPHIC STIMULATION IN ANDROGEN-DEFICIENT C57BL/10J MICE

Abstract

Worcester Foundation for Experimental Biology, Shrewsbury, Massachusetts 01545, U.S.A. (Received 24 May 1977) Deficient testicular function was suspected in male C57BL/10J mice from the observations that they have small testes (Shire & Bartke, 1972) and fail to produce the androgen-dependent pregnancy-blocking pheromone (Chapman & Whitten, 1969). Comparison with male DBA/2J mice and several other strains indicated that C57BL/10J mice have fewer spermatogonia, spermatocytes and spermatids, low testicular weight, a progressive decrease in the absolute weight of the testes after sexual maturation, excessive accumulation of esterified cholesterol in the testes and a low level of testosterone in the plasma (Bartke & Shire, 1972; Shire & Bartke, 1972; Bartke, 1974). The relative androgen deficiency of the C57BL/10J mice is also suggested by the observations of Ivanyi (1973), Hill, Clemens, Liu, Vessel & Johnson (1975) and Hoppe (1975). To define the causes of androgen deficiency in C57BL/10J mice, the levels of gonadotrophins in