运动对大鼠血小板L-精氨酸转运的影响

EFFECT OF EXERCISE ON L ARGININE TRANSPORT OF RAT PLATELETS

本工作在游泳大鼠模型上，观察血小板Ｌ－精氨酸（Ｌ－Ａｒｇ）转运特征，并观察凝血酶和ＰＡＦ对血小板Ｌ－Ａｒｇ转运的影响。结果发现，运动大鼠血小板Ｌ－Ａｒｇ转运明显高于未运动对照大鼠，表现在高亲和性最大转运速率（Ｖｍａｘ）明显增高（５０．５６±３．２７ｐｍｏｌ／１０８ｖｓ４５．８４±２．３６ｐｍｏｌ／１０８血小板／ｍｉｎ。Ｐ＜０．０５），米氏常数亦显著增加（２．１４±０．２３μｍｏｌ／Ｌｖｓ１．４６±０．１３μｍｏｌ／Ｌ，Ｐ＜０．０１）。应用刺激剂凝血酶和ＰＡＦ诱导运动大鼠血小板Ｌ－Ａｒｇ转运速率增加的幅度明显高于未运动对照大鼠（Ｐ＜０．０１）。实验结果表明，运动能增强血小板转运Ｌ－Ａｒｇ的效率。提示，运动可能促进血小板一氧化氮（ＮＯ）生成，抑制血小板聚集。

The present study observed the character of L arginine (L Arg) transport of platelets in swimming trained rats and the effect of thrombin and platelet activating factor (PAF) on L Arg transport of platelets. The results showed that L Arg transport of platelets in exercise rats was obviously higher than that in control rats. Maximum transport velocity (V max ) of the high affinity in exercise rats was also higher than that in control rats (50. 56±3. 27 pmol/min/10 8 vs 45. 84±2. 36 pmol/min/10 8 platelets, P <0. 05) and Michaelis Constant (Km) was also higher in exercise rats than that in the control (2. 14±0. 23 μmol vs 1. 46±0. 13 μmol/L, P <0. 01). The increase of L Arg transport induced by thrombin and PAF in platelets of exercise rats was also significantly higher than that in control rats ( P <0. 01). The above results indicated that exercise obviously enhanced L Arg transport in platelets, thus promoted platelet nitric oxide (NO) production and inhibited platelets aggregation. And consequently it might be suggested that adequate exercise may have preventive and therapeutic effect on cardiovascular obstructive diseases through its enhancing effect on L Arg transport of platelets.