大鼠脑内多巴胺受体超敏与Na^+-K^+-ATP酶活性变化的相关性研究

STUDIES ON THE CORRELATION BETWEEN THE SUPERSENSITIVITY OF DOPAMINE RECEPTOR AND THE ALTERATION OF Na +-K +-ATPase ACTIVITIES IN RAT STRIATUM,HIPPOCAMP AND CORTEX IN VIVO

目的研究超敏状态下多巴胺（ＤＡ）受体调节功能的变化与Ｎａ＋－Ｋ＋－ＡＴＰ酶活性变化的可能相关性。方法采用慢性连续给予ＤＡ受体拮抗剂的方法导致大鼠脑内ＤＡ受体的超敏，应用分光光度法测定Ｎａ＋－Ｋ＋－ＡＴＰ酶催化ＡＴＰ水解释放的无机磷（Ｐｉ）而确定酶的活性。结果急性给予利血平（０．５ｍｇ·ｋｇ－１，ｉｐ）、氯氮平（４０ｍｇ·ｋｇ－１，ｉｐ）和氟哌啶醇（１ｍｇ·ｋｇ－１，ｉｐ）对大鼠纹状体、海马和皮层Ｎａ＋－Ｋ＋－ＡＴＰ酶的活性均无显著影响；而以相同剂量的利血平、氯氮平和氟哌啶醇连续给药７ｄ和２１ｄ，利血平显著降低纹状体、海马和皮层Ｎａ＋－Ｋ＋－ＡＴＰ酶的活性，氟哌啶醇仅在给药２１ｄ时显著降低上述脑区Ｎａ＋－Ｋ＋－ＡＴＰ酶的活性，氯氮平对各脑区Ｎａ＋－Ｋ＋－ＡＴＰ酶的活性无显著影响。结论抗精神病药物导致的ＤＡ受体超敏时伴有纹状体和海马Ｎａ＋－Ｋ＋－ＡＴＰ酶活性的改变。

Objective To investigate the correlation between the changes of Na +-K +-ATPase activity and the supersensitivity of dopamine (DA) receptors in rat brain.Method The DA receptor supersensitivity was made by means of chronic treatment with DA receptor antagonists;Na +-K +-ATPase activity was assayed by colorimetric method.Results Na +-K +-ATPase activities in rat striatum,hippocamp and cortex had no significant changes after acute treatment with reserpine (0.5mg·kg -1 ,ip),clozapine (40mg·kg -1 ,ip) and haloperidol (1mg·kg -1 ,ip). Following continued administration of the drugs of the same dosage,the Na +-K +-ATPase activity in the above brain regions was markedly decreased by reserpine from 7d and by haloperidol from 21d. No changes were observed after the use of clozapine for 21d.Conclusion The changes of Na +-K +-ATPase activity may be an index for the supersensitivity of DA receptors in rat striatum, hippocamp and cortex.