L-NAME对电刺激内脏大神经传入纤维引起血压变化的影响

EFFECT OF L-NAME ON THE DEPRESSOR RESPONSE-INDUCED BY STIMULATING GREATER-SPLANCHNOAFFERENTS

目的：观察Ｌ－ ＮＡＭＥ对内脏－ 减压反应的影响，并探讨内脏疼痛引起休克的机理。方法：用电刺激内脏大神经传入纤维的方法模拟内脏痛，比较静脉注入Ｌ－ ＮＡＭＥ前后刺激神经时血压的变化情况。结果：用药后基础血压升高（ Ｐ＜０．０１）。用药前刺激神经时为降压反应，ΔＭＢＰ＝ － ４．１７ ±１．７９ｋＰａ，而用药后刺激时却为升压反应，ΔＭＢＰ＝ ＋ １．２２ ±１．９３ｋＰａ（ Ｐ＜０．００１）；注射Ｌ－ ＮＡＭＥ前先注入Ｌ－ 精氨酸，不管是基础血压还是刺激后的反应性血压，其变化均未达到统计学显著水平。结论：在大鼠身上刺激内脏大神经传入纤维可引起内脏－ 减压反应；发现了Ｌ－ ＮＡＭＥ 对上述反应有翻转作用。该作用的原因，可能是抑制了内源性一氧化氮的生成。

AIM To study the effect of L-NAME on the viscero-depressor response and to probe into the mechanism and the prevention of shock induced by visceral pain.METHOD The visceral pain was imitated by electric stimulation of the greater-splanchnoafferents.The basal blood pressure (BP) and the pressure responses to the electric stimulation were observed before or after intravenous injection of L-NAME.RESULTS The basal BP was increased after injection of L-NAME (P<0.01).When the nerve was stimulated without injection of L-NAME,BP was deceased by 4.17±1.79kPa,while the responsive BP was increased by 1.22±1.93kPa (P<0.001) after injection of L-NAME.If L-arginine was injected before L-NAME,both the basal BP and the responsive BP were unchanged (P>0.05).CONCLUSION The viscero-depressor response was induced by stimulating the greater-splanchnoafferents in rats,which would be reversed by L-NAME,due to the inhibition of the intrinsic nitric oxide synthesis.