[Concentration of basic fibroblast growth factor in plasma and cavernous corpus of aged rat]

To investigate the concentration of basic fibroblast growth factor (bFGF) in aged rat plasma and penile tissues.

Twelve 24-month-old rats and ten 12-week-old rats were selected. We assessed the erectile responses of rats to cavernous nerve electrostimulation. Then the concentrations of bFGF in the rats' plasma and penile tissues were detected by ELISA kit and smooth muscle contents in the rats' cavernous corpus were evaluated by masson trichrome staining.

Compared with the young rats, we found that the erectile function of the aged rats were significantly attenuated (The Max ICP/MAP in the aged rats were 0.41±0.05, 0.44±0.04 and 0.51±0.06 at 2.5 volts, 5.0 volts and 7.5 volts respectively while the Max ICP/MAP in the normal controls were 0.70±0.06, 0.75±0.07 and 0.81±0.04 at 2.5 volts, 5 volts and 7.5 volts respectively, P<0.05). The concentrations of bFGF [The bFGF levels in plasma and penile tissues in the aged rat were (6.43±0.51) μg/L and (598.6±51.7) pg/mg protein respectively while the bFGF levels in the normal control were (10.53±0.42) μg/L and (985.8±76.8) pg/mg protein] were significantly reduced (P<0.05). Furthermore, the smooth muscle contents in the aged rats' penile tissues (0.038±0.005) were dramatically decreased compared with the normal control (0.075±0.006, P<0.05).

The reduced levels of bFGF may be related to the decreased smooth muscle contents in the penile tissues of the aged rats.