目的:探讨老龄大鼠血清及阴茎海绵体中碱性成纤维细胞生长因子(basic fibroblast growth factor,b FGF)的含量。方法:12只24月龄SD雄性大鼠作为老龄大鼠组,10只12周龄SD雄性大鼠作为正常对照组。采用电刺激海绵体神经方法评价大鼠阴茎勃起功能,留取标本后ELISA方法检测血清和阴茎海绵体组织中b FGF水平,masson染色方法检测阴茎海绵体组织中平滑肌含量。结果:与正常对照相比,老龄大鼠的勃起功能明显下降(阴茎海绵内压/颈动脉压值在2.5、5.0和7.5 V电压刺激时分别为0.41±0.05 vs.0.70±0.06,0.44±0.04 vs.0.75±0.07和0.51±0.06 vs.0.81±0.04,P〈0.05),血清和阴茎海绵体组织中b FGF水平明显降低[分别为(6.43±0.51)vs.(10.53±0.42)μg/L,P〈0.05;(598.6±51.7)pg/mg protein vs.(985.8±76.8)pg/mg protein,P〈0.05],同时海绵体平滑肌含量也明显减少(大鼠阴茎组织平滑肌与胶原纤维的比值0.038±0.005 vs.0.075±0.006,P﹤0.05)。结论:阴茎海绵体组织中b FGF水平降低可能与海绵体平滑肌含量减少有关。
Objective: To investigate the concentration of basic fibroblast growth factor( b FGF) in aged rat plasma and penile tissues. Methods: 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 b FGF 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. Results: 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 and7. 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 b FGF[The b FGF 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 b FGF 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). Conclusion: The reduced levels of b FGF may be related to the decreased smooth muscle contents in the penile tissues of the aged rats.