Selective effects of testosterone and isoproterenol upon regenerating submandibular gland isografts in BALB/c mice

Single submandibular glands were isografted intraperitoneally to normal BALB/c mice. From the day following transplantation, 20 mg testosterone enanthate fortnightly, or daily intraperitoneal injections of 0.25 mg per gram body weight of isoproterenol‐HCl were given. Control mice were untreated. The grafts were removed from five mice in each group 1, 2, 4, or 8 weeks after grafting. Regardless of treatments, only ductal cells were observed one week after transplantation. With testosterone treatment for longer than two weeks, their remaining ductal cells tended to accumulate secretory granules. Some appeared to be secretory tubules resembling those in the glands of normal adult male mice. When the glands were transplanted from females to male hosts, surviving grafts responded to endogenous androgen of the hosts, and some secretory tubules reappeared without testosterone treatment. Contrarily, with isoproterenol treatment for longer than two weeks, acinar cells reappeared in the grafts, but no secretory tubules were observed. The remaining ductal cells often underwent hyperplastic changes with reappearing tubules or acinar cells amongst them corresponding to post‐transplantational treatment. Mechanisms of differentiation of these three different components of submandibular glands were found to be different and each had specific affinity to testosterone or isoproterenol. Grafts were removed from hosts treated with testosterone for two months, and when 4 or 8 of these grafts were retransplanted into each new host, they demonstrated a lethal effect.