冷暴露对大鼠脑组织游离氨基酸含量的影响

Effects of cold exposure on free amino acids content in rat brain tis-sue

作者将Wistar大鼠90只分为对照组(22±3℃)和低温组(0±2℃).经冷暴露1,2,3,4,5,7,9和11周后,用氨基酸分析仪测定大鼠全脑组织中14种游离氨基酸的含量.在冷暴露1周,Pro,Val,IIc,Leu和Tyr高于对照(P<0.01);在冷暴露2周,Arg上升、Ala下降(P<0.01),其它氨基酸均无显著变化(P>0.05);在冷暴露3-5周,Ala,Arg,Lcu,Phc,Tyr,Lys,Pro,Gly,His,Mct和IIc升高,7周达到最高值(P<0.01);9周后所有氨基酸含量趋于稳定,其中Val,Pro和Gly恢复到对照组水平(P>0.05).Glu和Asp低于对照组(P<0.01),其余氨基酸均高于对照组(P<0.01).结果提示:冷暴露对大鼠脑组织游离氨基酸含量的影响呈规律性变化,1周为波动期,2周为恢复期,3—7周为升高期,9—11周为稳定期.

Ninety Wistar rats were divided into control group (25± 3℃)and cold - exposured group (0 ±2 ℃). After 1, 2, 3, 4, 5, 7, 9 and 11 weeks of cold exposure (CF.), whole brain tissue was taken out and the content of 14 free amino acids (FAA )in rat- brain tissue was measured with amino aad analyzer . In the 1st week of CF , the content of Pro , Val , Ile , Leu , Tyr was obviously higher than that of the control group ( P<0.01 ): in the 2nd week , no difference was discovered in all amino acids (P>0.05 ) except that Arg increased and Ala decreased (P<0.01 ); during the 3rd to 5th weeks , the content of Ala , Arg , Leu , Phc , Tyr , Lys . Pro , Gly , His , Met and Ile increased (P<0.05 ) and by the end of the 7th week the foregoing 11 amino adds reached their apex (P< 0.01); in the 9th week and from then on the content of all FAA tended to be constant ( P>0.05 cs the 11th CF. week ), with Val , Pro and Gly back to normal the control group ( P>0.05 ), and Glu and Asp lower than the control group (P<0.01 )and all the other amino acids higher than the control group ( P<0.01 ). These results indicate that the effect of CF. on FAA content in rat brain tissue is one of penodic changes with the 1st week as the fluctuational period , the 2nd week as the recovery period , the 3rd - 7th weeks as the increase period and the 9th - llth weeks as the constant period .