Precocious induction of secretory granules by hormones in convoluted tubules of mouse submandibular glands.

Precocious differentiation of convoluted tubules of the submandibular glands of mice was induced by daily injection of thyroxine, insulin, hydrocortisone and 5alpha-dihydrotestosterone from day 4 after birth. This treatment induced enlargement of the tubules and synthesis of secretory granules in the tubules. Treatment with 5alpha-dihydrotestosterone alone had no effect on enlargement of the tubules or synthesis of the granules. These findings suggest that, besides androgenic hormones, these three hormones are also involved in synthesis of granules in developing mice.