大鼠血浆唾液酸水平变化的中枢调节机制

THE CENTRAL REGULATION OF THE CHANGES OF THE RAT PLASMA SIALIC ACID LEVEL

1目的 探讨大鼠血浆唾液酸 (SA)水平变化的调节机制。 2方法 采用紫外分光光度法 ,测定乌拉坦麻醉、侧脑室注射多巴胺 (DA)及弓状核 (ARC)区注射谷氨酸钠 (Glu)等后大鼠血浆 SA水平的变化。3结果 乌拉坦麻醉组血浆 SA水平较对照组明显降低 (t=3.2 0 ,P<0 .0 5 ) ;侧脑室注射 DA后 ,血浆 SA水平较注射前明显降低 (F=3.2 9,q=4.2 6 ,P<0 .0 5 ) ,与同一时间对照组相比 ,亦明显降低 (t=2 .5 7,P<0 .0 5 ) ;ARC区注射胞体兴奋剂 Glu溶液 15 ,2 5 m in后 ,血浆 SA水平较注射前明显降低 (F=8.45 ,q=4.90 ,6 .31,P<0 .0 5 ) ,与同一时间对照组相比 ,亦明显降低 (t=2 .35 ,2 .41,P<0 .0 5 ) ,且此效应可被侧脑室注射 DA受体阻断剂 (螺哌啶酮 )阻断。 4结论血浆 SA水平变化受神经和体液因素调节 ,此调节机制与中枢神经递质 DA有关 ,且 ARC可能是此效应的主要调节中枢部位。

Objective To study the regulating mechanism of plasma sialic acid (SA) level in rats. Methods The spectrophotometry were used to study the effect of urethane anesthasia, microinjection of dopamine (DA) into the lateral ventricle and microinjection of Glu into nucleus arcuatus (ARC) on plasma SA level. Results In anesthesia group, the plasma SA level was significantly decreased compared with the control group (t=3.20,P< 0.05 ); After microinjection of DA into LV, the plasma SA level decreased significantly than that before injection(F=3.29,q= 4.26 , P< 0.05 ), and that of the control group(t=2.57, P< 0.05 ); After microinjection of Glu into ARC, the plasma SA level was significantly decreased compared with that before injection(F=8.45,q=4.90,6.31,P<0.05), and that the control group(t= 2.35 , 2.41 , P< 0.05 ),and this effect can be blocked by DA receptor antagonist spiperone. Conclusion The changes of plasma SA level are regulated by the neuro hormonal system, and the mechanism is related to central neurotransmitter DA. And the ARC is the possible central site of this effect. [