Aging-related severe hypertension causes prostatic gland atrophy and testicular injury in rats

The combined effects of aging and hypertension on the male reproduction system remain unclear. We investigated these effects on prostate and testis from histological and endocrinological perspectives. Male spontaneously hypertensive rats (SHRs) and normotensive Wistar Kyoto rats (WKYs) (n = 8 per group) were evaluated at 36 weeks (adult) and 72 weeks (aged). Compared with age-matched WKYs, adult SHRs showed significantly higher prostate weight, prostate weight-to-body weight ratio and glandular epithelial area in the ventral prostate. On the contrary, aged SHRs showed significantly lower prostate weight and outer glandular perimeter than age-matched WKYs. At both ages, SHRs had significantly higher blood pressure and lower prostatic blood flow than age-matched WKYs, and aging-dependent increase in the blood pressure was observed in SHRs but not in WKYs. Aged SHRs had significantly lower serum testosterone levels, higher testicular weight-to-body weight ratios, seminiferous epithelial desquamation and neutrophil infiltration than aged WKYs, while these alterations were not obvious in adult SHRs. In conclusion, whereas adult SHRs exhibit prostatic hyperplasia, aged SHRs exhibit severe hypertension, prostatic atrophy, testicular injury, and reduced serum testosterone levels. Aging-related severe hypertension may be a risk factor for prostatic atrophy which might be related to reduced testosterone levels.