呼吸性酸碱失衡家兔肾脏内髓集合管细胞单层H+/K+交换功能及cH-K-ATP酶mRNA表达的实验研究

为了研究呼吸性酸碱失衡时内髓集合管（IMCD）细胞病理生理学改变，分别以3％CO2和10％CO2模拟慢性呼碱和慢性呼酸家兔肾脏IMCD细胞培养模型，对照组用5％CO2。荧光探针法测定IMCD细胞H^ /K^ 交换功能，原位杂交和RT－PCR检测IMCD细胞cH－K－ATP酶mRNA表达。结果显示，呼酸组H^ /K^ 交换显著高于对照组（P＜0．05），呼酸组cH－K－ATP酶mRNA原位杂交积分光密度和RT－PCR积分光密度比值均非常显著地高于对照组（P＜0．01）；而这三项指标，对照组与呼碱组之间差异均无显著性意义（P＞0．05）。提示慢性呼酸显著增加IMCD细胞H^ /K^ 交换和cH－K－ATP酶mRNA表达，慢性呼碱有抑制和下调趋势，但差异无显著性意义，其原因尚待进一步研究。

EXPERIMENTAL STUDY ON H+/K+ EXCHANGE FUNCTION AND cH-K-ATPase mRNA EXPRESSION IN RENAL IMCD CELL MONOLAYER UNDER RESPIRATORY ACID-BASE DISORDERS IN RABBIT

To study the cellular pathophysiological change in kidney IMCD cell under respiratory acid base disorders. 3% or 10% CO 2 was used to initiate chronic respiratory alkalosis(ALG) or chronic respiratory acidosis(ACG) of cultured rabbit IMCD cell. 5% CO 2 was used in control group(CG). Fluorescent probe was used to measure H + /K + exchange function of these cells. In situ hybridization and RT PCR were used to measure cH K ATPase mRNA expression of these cells.The results showed that H + /K + exchange in ACG was significantly higher than that in CG ( P <0 05), the accumulation light density ratio of cH K ATPase mRNA in situ hybridization and the accumulation light density ratio of cH K ATPase mRNA with RT PCR in ACG were siginificantly higher than those in CG( P <0 01).There was no siginificant difference among the three indexes between CG and ALG ( P >0 05). It is suggested that chronic respiratory acidosis could induce an increase in H + /K + exchange function and cH K ATPase mRNA expression. However, chronic respiratory alkalosis could induce decreases in H + /K + exchange function and cH K ATPase mRNA expression with no statistical significance, the reason of which calls for further study.