Biodynamic Studies of Hamster Flank Organ Growth: Hormonal Influences

The biodynamic response of flank organs of male and female hamsters to androgenic stimulation has been studied by autoradiographic and electron microscopic techniques, as well as by routine histology and gross observation. Intraperitoneal administration of 2.5mg of testosterone on alternate days resulted in bilateral increase in palpable bulk, and pigmentation of flank organs of females, males, and castrated males. Topical application of testosterone, dihydrotestosterone (DHT), methyltestosterone, or androstenedione to one flank organ of females resulted in unilateral stimulation of sebaceous gland growth and pigmentation. Androsterone, epiandrosterone, and progesterone did not cause flank organ growth or increased pigmentation when applied topically. Histologic changes in flank organs of castrated males following testosterone administration are described. Auto0radiographic studies indicate a decrease in the labeling index of flank organ sebaceous gland cells within 20 hours after castration and a subsequent significant increase in the labeling index within 10 hours after a single intraperitoneal administration of 2.5mg of testosterone. Pigmentation of flank organs is due to the presence of dendritic cells in the dermis which contain dense structures resembling stage IV melanosomes