RADIOIMMUNOASSAY OF MOUSE VAS-DEFERENS PROTEIN - DEVELOPMENTAL PROFILE AND HORMONAL-REGULATION

This study investigated the hormonal regulation of the developmental p attern of a major protein of the mouse vas deferens (MVDP) which repre sents 10% of the vas deferens protein content. Using a specific radioi mmunoassay, MVDP was first detected in 10-day-old males and its concen tration increased sharply between 10 and 30 days, reaching adult level s at 40 days. In adult males, MVDP disappeared after castration, and t estosterone treatment for 15 days was necessary to reverse the effect of castration completely. In 10-day-old mice castrated at birth, MVDP levels were similar to those measured in controls of the same age. Tes tosterone administration from 1 to 10 days of age did not induce preco cious accumulation of MVDP. These results suggested that the neonatal expression of MVDP is independent of androgens. From 10 to 30 days, th e increase in MVDP levels was androgen-dependent as shown by the castr ation and injection experiments. In males castrated at birth, the andr ogen-induced accumulation of MVDP was greatly reduced in adulthood. Th is suggested that neonatal androgens are necessary to obtain full expr ession of the MVDP gene in adults.