Kiyohara T, Okuno M, Ishikawa H, Nakanishi T, Shinomura Y, Yanaihara C, Matsuzawa Y
Second Department of Internal Medicine, Osaka University Medical School, Japan.
Am J Physiol. 1992 Oct;263(4 Pt 1):G502-7. doi: 10.1152/ajpgi.1992.263.4.G502.
Effects of rat and porcine galanin on rat intestinal ion transport were examined in vitro. In the rat distal colon, a sustained increase in short-circuit current (Isc) was produced by the serosal addition of rat galanin at a concentration as low as 10(-9) M, and a maximal increment was observed at 10(-7) M. Porcine galanin was approximately 100 times less potent than rat galanin. In the rat jejunum, rat galanin produced only a slight and transient decrease in basal Isc. The response to rat galanin was not influenced by atropine, hexamethonium, or amiloride, but was virtually abolished by tetrodotoxin or furosemide. Rat galanin did not significantly influence the increase in Isc elicited by electrical field stimulation in the rat colon and jejunum. Transmural unidirectional 22Na and 36Cl fluxes in the rat colonic mucosa were measured under short-circuited conditions, and rat galanin significantly decreased net sodium and net chloride absorption. These findings suggest that galanin acts as a secretory modulator in the rat colon via noncholinergic neural transmission.
在体外研究了大鼠和猪甘丙肽对大鼠肠道离子转运的影响。在大鼠远端结肠，通过在浆膜侧添加低至10(-9)M浓度的大鼠甘丙肽，短路电流（Isc）持续增加，在10(-7)M时观察到最大增量。猪甘丙肽的效力约为大鼠甘丙肽的1/100。在大鼠空肠，大鼠甘丙肽仅使基础Isc轻微且短暂降低。大鼠甘丙肽的反应不受阿托品、六甲铵或氨氯吡咪影响，但几乎被河豚毒素或呋塞米消除。大鼠甘丙肽对大鼠结肠和空肠中电场刺激引起的Isc增加无显著影响。在短路条件下测量大鼠结肠黏膜的跨壁单向22Na和36Cl通量，大鼠甘丙肽显著降低钠和氯的净吸收。这些发现表明甘丙肽通过非胆碱能神经传递在大鼠结肠中作为分泌调节剂起作用。
