Distribution of soltriol [1,25(OH)2-vitamin D3] binding sites in male sex organs of the mouse: an autoradiographic study.

After injection of [3H]-1,25(OH)2-vitamin D3 (soltriol), nuclear labeling is found in Sertoli cells of testes, being highest at the stage of spermiosis, in epithelium of efferent ductules and caput epididymidis and in connective tissue cells of epididymis, in lamina propria and muscular sheath of deferent duct, and in epithelium and muscular sheath of dorsal and ventral prostate of the mouse. This labeling pattern is characteristic for [3H]-soltriol and differs from that for [3H]-dihydrotestosterone and [3H]-estradiol, although with overlap. The nuclear labeling with [3H]-soltriol suggests an action of the hormone on certain processes during spermatogenesis, on sperm maturation, on epididymal fluid resorption, and on secretion and transport of spermatozoa.