【摘要】 利用全细胞膜片钳技术 ,在用胶原酶急性分离的豚鼠胃窦环行肌细胞上观察了外源性花生四烯酸 (arachidonicacid ,AA)及其它不饱和脂肪酸对容积敏感氯电流 (volume sensitivechloridecurrent,VSCC)的影响。细胞膜电位钳制在- 6 0mV条件下 ,低渗性细胞膨胀激活VSCC。当给予按 2 0mV间隔的去极化阶跃性方波刺激时 ,VSCC的电流 电压曲线具有外向性整流的特点 ,并表现出去极化到 +40mV以上时呈现时间依赖性衰减的特点。AA呈齐量依赖性地抑制VSCC ,而对VSCC的随时间衰减部分的抑制效应更明显。其它不饱和脂肪酸 ,如含有 2个双键的亚油酸 (Linoleicacid,LA)、含有 1个双键的油酸 (Oleicacid ,OA)也抑制VSCC ,抑制强度顺序为AA >LA >OA ,但饱和脂肪酸 (stearicacid,SA)对VSCC无抑制作用。提示外源性不饱和脂肪酸抑制VSCC ,其抑制效应在VSCC的随时间衰减部分更明显。外源性不饱和脂肪酸对VSCC的抑制作用可能与脂肪酸链中的双键数目有关更多还原

【Abstract】 In order to investigate the effect of unsaturated fatty acids on volume sensitive chloride current the whole cell patch clamp technique was used in the myocytes isolated by collagenase in antral circular myocytes of guinea pig stomach. Hypoosmotic cell swelling activated volume sensitive chloride currents (VSCC), the VSCC exhibited time dependent attenuation when membrane potential depolarized above +40mV and outward rectifier in I V curve. Arachidonic acid (AA) significantly inhibited VSCC in a dose dependent manner and the inhibitory effect was more significant on the part of time dependent attenuation. Linoleic acid (LA) and Oleic acid (OA) also inhibited VSCC. The inhibitory potency of unsaturated fatty acids was AA > LA > OA. Saturated fatty acid, stearic acid(SA) didn’t inhibit VSCC. The results suggest that exogenous unsaturated fatty acids inhibit VSCC and the inhibitory effect is more significant on the part of time dependent attenuation; The inhibitory effects of exogenous unsaturated fatty acids on VSCC are related to double bonds in fatty acid chain.更多还原