1,25(OH)2 VITAMIN-D(3) BINDING-SITES IN MALE SEX-ORGANS OF THE SIBERIAN HAMSTER (PHODOPUS-SUNGORUS) - AN AUTORADIOGRAPHIC STUDY

Using autoradiography binding sites for 1,25(OH)2 vitamin D3 are found in certain genital organs of male Siberian hamsters (Phodopus sungoru s), in particular in basal epithelial cells and fibroblasts of the lam ina propria of prostate glands. Scattered labeled cells are also prese nt in the epithelium of coagulation and urethral glands. In contrast t o the findings in mice, under the conditions of the experiment, 1,25(O H)2 vitamin D3 binding sites are not recognizable in other accessory s ex glands and gonads. The frequency of basal epithelial cells with [H- 3]1,25(OH)2 vitamin D3 nuclear binding is higher in regressed dorsal p rostate glands of animals living in short photoperiods. The data sugge st that 1,25(OH)2 vitamin D3 may promote proliferation and differentia tion in basal epithelial cells, modulated by the seasonal and function al status of the animal.