睾酮对大鼠心肌梗塞后心肌肥大的影响

本文应用立体形态定量技术,观察睾酮(T)对心肌梗塞后心肌肥大的影响。实验分为:假手术组(S组)、心肌梗塞组(MI组)。心肌梗塞后睾酮治疗组(MIT组)。结果证明,与S组相比,MI及MIT组大鼠心肌细胞核密度明显减少,尤其以MIT组变化显著,MIT组平均核长度明显增加;MI组的 dp/dt max明显降低,T值延长,MIT组的上两指标无显著差异。MI后血浆T总浓度与平均每核心肌细胞体积呈显著正相关关系。提示:睾酮确实促进了MI后心肌肥大,从而促进了心功能的恢复。

Effect of testosterone on myocardial hypertrophy and cardiac function after myocardial infarction in rats

To determine the effects of testosterone (T) on hypertrophy and cardiac function of rats with myocardial infarction (MI), the rats were divided into 3 groups: ie, the sham-operated group (S group), the coronary artery ligating groups with or without the injection of T (MIT and MI group). T level of plasma was tested on all rats, by RIA on1/4, 1, 3, 9, 20 day after operation; then the nuclear profiles per unit area of myocardium N_((n)A) the average nuclear length D_((n)) and the volume fraction of number of myoeytes in the myoeardium V_((m)v) were measured under microscope; The number of myocyte nuclei per unit ovolume of myocardium N_((n)v) and average myocyte cell volume per nucleus V_((m)n) were calculated. The results were as follows: (1) Comparing with S group N_((n)A), N_((n)v) and V_((m)n) in MI had marked changes (P<0.01) while D_((n)) of the MI group increased insignificantly (P>0.05). Of all the mentioned changes were more marked in MIT group than that in MI group. (2) The total plasma concentration of T was correlated with V_((m)n) (r=0.60, P<0.01). (3) Compared with S group. dp/dt max was reduced (P<0.05) while T value was prolonged (P<0.05) in MI group, but notable different (P>0.05) were not found in MIT rats. These results indicated that T may improve myocardial hypertrophy and promote the recovery of eardial function of MI.