通过分离的鱼皮（奇异吉利鱼）进行的活性氯化物转运的钠依赖性。

Sodium dependency of active chloride transport across isolated fish skin (Gillichthys mirabilis).

作者信息

Marshall W S

出版信息

J Physiol. 1981;319:165-78. doi: 10.1113/jphysiol.1981.sp013899.

DOI:10.1113/jphysiol.1981.sp013899

PMID:7320911

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC1243829/

Abstract

The effects of thiocyanate, ouabain, ion-substituted Ringer solution and electrochemical gradients on Na+ and Cl- transport were examined using the isolated skin of the marine teleost, Gillichthys mirabilis. 2. Bilateral replacement of Na+ with choline in the bathing solutions reduces net Cl- flux by 93%, indicating that active Cl- transport by the skin is Na-dependent. 3. Thiocyanate inhibits short-circuit current with an ED50 of 6.4 x 10(-4)M, and, at 10(-2)M, decreases Cl-efflux, influx, net flux and short-circuit current by 68, 33, 74 and 81%, respectively. 4. Ouabain (10(-5)M) reduces Cl- efflux and net flux by 56 and 86%, respectively, indicating that the Cl- transport requires Na,K-ATPase. 5. Subsequent addition of thiocyanate to ouabain-treated skin reduces Cl- efflux, net flux and short-circuit current, suggesting that the two agents operate at different sites involved in Cl- transport. 6. Unilateral substitution of gluconate for Cl- on the serosal side does not affect Cl- influx, indicating that Cl- passive transport is via Fickean diffusion, not Cl-Cl exchange diffusion. 7. The addition of NaCl to the mucosal side, which mimics the in vivo sea-water condition, increases Cl- influx and transepithelial potential and decreases tissue resistance. The net flux (secretion) of Cl- with hypertonic saline on the mucosal side (0.51 +/- 0.06 muequiv/cm2 . hr) demonstrates that the skin could secrete Cl- in vivo. 8. Na+ fluxes across the skin are passive, as the observed flux ration (efflux/influx) is similar to that predicted by the Ussing-Teorell equation under both closed- and open-circuit conditions. 9. The permeability ratio (PNa:PCl) in approximately 5.4:1.0, indicating that the skin is more permeable to Na+, and that at least part of the serosa-positive transepithelial potential may be a Na+ diffusion potential. 10. The results suggest that Cl- secretion by Gillichthys skin is secondary active transport involving Na,K-ATPase and serosal Na+.

摘要

使用海洋硬骨鱼奇异银汉鱼的离体皮肤，研究了硫氰酸盐、哇巴因、离子替代林格液和电化学梯度对Na⁺和Cl⁻转运的影响。2. 在浸泡溶液中用胆碱双侧替代Na⁺可使净Cl⁻通量降低93%，表明皮肤的主动Cl⁻转运是Na⁺依赖性的。3. 硫氰酸盐抑制短路电流，ED50为6.4×10⁻⁴M，在10⁻²M时，Cl⁻外流、内流、净通量和短路电流分别降低68%、33%、74%和81%。4. 哇巴因（10⁻⁵M）分别使Cl⁻外流和净通量降低56%和86%，表明Cl⁻转运需要Na⁺,K⁺-ATP酶。5. 在经哇巴因处理的皮肤中随后添加硫氰酸盐可降低Cl⁻外流、净通量和短路电流，提示这两种药剂作用于Cl⁻转运的不同位点。6. 在浆膜侧用葡萄糖酸盐单侧替代Cl⁻不影响Cl⁻内流，表明Cl⁻的被动转运是通过菲克扩散，而非Cl⁻-Cl⁻交换扩散。7. 在黏膜侧添加NaCl，模拟体内海水条件，可增加Cl⁻内流和跨上皮电位，并降低组织电阻。黏膜侧用高渗盐水时Cl⁻的净通量（分泌）（0.51±0.06微当量/平方厘米·小时）表明皮肤在体内可分泌Cl⁻。8. 皮肤的Na⁺通量是被动的，因为在闭路和开路条件下观察到的通量比（外流/内流）与乌斯辛-特奥雷尔方程预测的相似。9. 渗透比（PNa:PCl）约为5.4:1.0，表明皮肤对Na⁺的通透性更高，并且浆膜侧正向跨上皮电位的至少一部分可能是Na⁺扩散电位。10. 结果表明，奇异银汉鱼皮肤的Cl⁻分泌是涉及Na⁺,K⁺-ATP酶和浆膜Na⁺的继发性主动转运。