实验性膜迷路积水活体Ca^（2＋）浓度与内淋巴电位测定

Measure men t of Ca￣(2+) Concentration and Endocochl ear Potentlal in Experimental Endolymphatic Hydrops in Vivo

为了探索Ｍｅｎｉｅｒｅ病发病机理，阻塞豚鼠内淋巴囊造成膜迷路积水模型。对膜迷路积水成功的１７只动物的左耳分别于术后１、２、３个月在耳蜗第三回开窗，用双管离子选择性微电极插入中阶，测Ｃａ￣（２＋）浓度及内淋巴电位（ＥＰ）；１４只豚鼠健耳（右耳）作为对照。结果证明积水后中阶Ｃａ￣（２＋）浓度增高，与对照耳比较差异有显著性，随积水时间延长Ｃａ￣（２＋）浓度逐渐增高，且１、２、３个月之间差异有显著性。对照耳ＥＰ为７２．７８±１．９ｍＶ，积水耳为５５．８２±３．２８ｍＶ，差异有显著性。积水时间越长ＥＰ下降越明显，与Ｃａ￣（２＋）浓度呈负相关，按Ｎｅｒｓｔｉａｎ方程计算电化学梯度的斜率。两者之间差有显著性。对Ｍｅｎｉｅｒｅ病听力下降的原因、Ｃａ￣（２＋）浓度与ＥＰ的关系进行讨论。

This study washsed on obscrvations on 14 normal guinea pigs and 17 guinea pigs in which the left endolymphatic duct and sac had been surgically obliterated to induce endolymphatic hy-drops. Three groups of hydropic animals were tested 1, 2 and 3 months after surgery. The Ca￣(2+)concen-tration and endocochlear potential(EP)were recorded by means of double-barrelled ion selective micro-electrtxle in the third turn of the cochlea. The results indicated that a decrease in EP and an increase inCa￣(2+) in hydropic cochlea,a negative correlation was present.In the control ear,the values of Ca￣(2+) and EP were 26.4±0. 33μm/L(n=14)and 72. 78 mV (n=14),respectively;in the hydropic ear,the val-ue of Ca￣(2+) was 404. 47±79. 74 μm/L(n=17),while the EP was 55.82±3.28mV(n=17).Accord-ing to Nerstian formula,the slope of electrochemical gradient in the control was 31mV/decade(n=14),but in the hydropic ear it increased to 72.5mV/decade change in Ca￣(2+)(n=17).The statistical analysis showed significant difference between the control and hydropic ears. The changes were progressive and became more pronounced as the duration of hydrops prolonged.The cause of hearing loss in the Meniere's disease and the relation between the EP and Ca￣(2+) concentration had been discussed.