NMDA receptor antagonist blocks the bradycardic but not the pressor response to L-glutamate microinjected into the nucleus tractus solitarius (NTS) of unanesthetized rats

被引:29
作者
Colombari, E
Bonagamba, LGH
Machado, BH
机构
[1] UNIV SAO PAULO,SCH MED,DEPT PHYSIOL,BR-14049 RIBEIRAO PRET,BRAZIL
[2] UNIFESP,ESCOLA PAULISTA MED,DEPT PHYSIOL,BR-04023900 SAO PAULO,SP,BRAZIL
基金
巴西圣保罗研究基金会;
关键词
excitatory amino acid receptor; phosphonovaleric acid; cardiovascular regulation; cardiovagal excitation; sympatho-excitation; autonomic regulation;
D O I
10.1016/S0006-8993(96)01169-9
中图分类号
Q189 [神经科学];
学科分类号
071006 ;
摘要
In the present study we evaluated the role of NMDA receptors on the presser and bradycardic responses to L-glutamate (L-Glu) microinjected into the nucleus tractus solitarius (NTS) of unanesthetized rats. L-Glu (1 nmol/100 nl) was microinjected into the NTS before and 10 min after microinjection of phosponovaleric acid (AP-5), a selective NMDA receptor antagonist, into the NTS of three different groups of rats (0.5, 2.0 and 10.0 nmol/100 nl). Microinjection of AP 5 into the NTS produced a dose-dependent reduction in the bradycardic response to L-Glu. However, no significant change in the presser response to L-Glu was observed. These results indicate that the activation of the cardiovagal component (bradycardia) by L-Glu involves NMDA receptors and suggest that the activation of the sympatho-excitatory component (presser response) by L-Glu in the commissural NTS is mediated by non-NMDA receptors. (C) 1997 Elsevier Science B.V.
引用
收藏
页码:209 / 213
页数:5
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