1. Using a preparation of rat colon mucosa mounted in vitro in small chambers, some factors which influence the electrical properties of the mucosa have been investigated.2. The mucosa behaved mainly as an ohmic resistance although a very brief transient occurred on first passing current. At 32° C, the fresh preparation had a mean resistance of 108Ω/cm2 and a mean short circuit current (s.c.c.) of 143 μA/cm2. Tissues taken from Na-depleted and adrenalectomized rats differed little from normal tissues in electrical resistance but those from Na-depleted rats had higher potential difference (p.d.) and s.c.c.3. Increase of temperature led to a rise of conductance of similar order to that found for ions in aqueous solution. S.c.c. also rose with increase of temperature but the effect was relatively greater consistent with its being dependent on metabolic processes.4. Anoxia or the addition of cyanide, iodoacetate or 2,4-dinitrophenol to the bath fluid caused considerable fall in the p.d. and s.c.c.5. Ouabain decreased the p.d. and s.c.c. when added to the serosal side but had no effect when on the luminal side.6. Aldosterone and acetazolamide had no effect.7. Varying serosal side [K] produced only minor changes in p.d.8. Reducing [Na] of the luminal solution caused a considerable fall of p.d. but similar reduction of [Na] on the serosal side had little effect.9. The frequently employed model which represents the transepithelial p.d. as the sum of diffusion potentials originating at the luminal and serosal sides of the cell layer is not consistent with the present results. The colonic transmucosal p.d. probably originates in the electrogenic transport of Na by a mechanism located on the serosal side of the epithelium.
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机译:1.采用体外小室制备的大鼠结肠粘膜制剂,研究了影响粘膜电学特性的一些因素。2。粘膜主要表现为欧姆电阻,尽管在首次通过电流时发生了非常短暂的瞬变。在32°C下,新鲜制剂的平均电阻为108Ω/ cm 2 sup>,平均短路电流(s.c.c.)为143μA/ cm 2 sup>。贫钠和肾上腺切除的大鼠的组织与正常组织的电阻差异不大,但贫钠的大鼠的组织具有更高的电位差(p.d.)和s.c.c.3。温度的升高导致电导的增加与水溶液中离子的电导相似。 S.c.c.随着温度的升高,其含量也上升,但效果相对更大,这取决于其对代谢过程的影响。4。缺氧或在浴液中添加氰化物,碘乙酸盐或2,4-二硝基苯酚会导致日平均沉降显着下降。和s.c.c.5。瓦巴因降低每日收入。和s.c.c.当添加到浆膜侧时,但当在腔侧时没有影响6。醛固酮和乙酰唑胺无作用。7。浆膜侧面[K]在第8页仅产生微小变化。管腔溶液的[Na]降低导致p.d的显着下降。但是在浆膜侧[Na]的类似减少几乎没有效果。9。代表跨上皮p.d.的常用模型因为起源于细胞层腔和浆膜侧面的扩散电位之和与当前结果不一致。结肠透粘膜p.d.可能是由于上皮浆膜侧的机制而导致Na的电迁移。
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