OBJECTIVETo investigate the changes of the expressions of the nerve growth factor (NGF) and its mRNA in the prostate tissues of spontaneously hypertensive rats (SHR) of different ages and their significance.

METHODSSHRs and normotensive Wistar Kyoto (WKY) rats were killed at 1 month (young), 6 months (adult) and 12 months (aging), respectively, 5 in each group. Their prostate indexes were calculated, and the expressions of NGF and its mRNA in the ventral prostate tissue were detected by immunohistochemistry and RT-PCR.

RESULTSThe prostate indexes of the SHR and WKY groups were 1.16 +/- 0.06 and 1.03 +/- 0.09 at 1 month, 1.12 +/- 0.14 and 0.93 +/- 0.07 at 6 months, and 1.11 +/- 0.05 and 0.96 +/- 0.09 at 12 months, significantly higher in the former group than in the latter either at 6 or at 12 months (P < 0.05), but with no obvious difference at 1 month (P > 0.05). The expressions of NGF and its mRNA in the ventral prostate tissue were detected in all groups, and elevated gradually with the increase of age (P < 0.05). Among those of the same age, the expression levels were markedly higher in the SHR than in the WKY group (P < 0.05).

CONCLUSIONIn SHRs with benign prostate hyperplasia (BPH), the enhanced excitation of the sympathetic nervous system may be a common mechanism underlying BPH and hypertension, and NGF plays an important role in it.