Weights of testes, seminal vesicles, ventral prostate and pituitary, plasma testosterone and LH concentrations, pituitary LH content and concentration, the LH in-vivo response after LHRH administration (1 μg), and basal and LHRH-stimulated secretion in vitro were analysed in adult male spontaneously hypertensive (SH) and normotensive control (WKY) rats.
Spontaneously hypertensive rats showed: (1) testis and pituitary hypertrophy; (2) seminal vesicle and ventral prostate atrophy; (3) increased plasma testosterone and LH concentrations; (4) increased pituitary LH content and concentration; (5) unchanged net increase of plasma concentrations of LH 15 and 45 min after administration of 1 μg LHRH; and (6) increased basal LH secretion in vitro with a normal response to LHRH stimulation.
These results provide evidence that SH rats show increased LH secretion with a normal response to LHRH stimulation. The coexistence of high plasma concentrations of testosterone with seminal vesicle and ventral prostate atrophy suggest a reduction in the effectiveness of testosterone in these structures.
J. Endocr. (1987) 113, 255–260