Gullikson G W, Virina M A, Loeffler R, Erwin W D
Gastrointestinal Diseases Research Department, G.D. Searle and Co., Skokie, IL 60077.
Am J Physiol. 1991 Sep;261(3 Pt 1):G426-32. doi: 10.1152/ajpgi.1991.261.3.G426.
Motility-stimulating drugs can increase gastric antral and intestinal contractions but do not usually enhance emptying unless gastroparesis is present. An alpha 2-adrenergic agonist (SC-39585A) was used to inhibit antroduodenal motility and simulate gastroparesis in dogs. SC-39585A caused dose-related inhibition of emptying of solid and liquid meals as well as the antral and duodenal motility responses to the solid meal. The motility-enhancing agent renzapride (100 micrograms/kg iv) did not enhance emptying of the solid meal under nondelayed conditions. However, at the same dose it partially reversed the delay in solid emptying but only when antroduodenal motility was incompletely (30 micrograms/kg sc) and not totally (100 micrograms/kg sc) inhibited by SC-39585A. This was done in part by antagonizing antral but not duodenal inhibition of motility. Renzapride was also effective orally in reversing the delay in solid emptying. Similarly, renzapride reversed the delay in liquid emptying caused by SC-39585A (30 micrograms/kg sc). An alpha 2-adrenergic agonist can be used to model gastroparesis in dogs by inhibiting antroduodenal motility and can also be used to examine the actions of motor stimulants, such as renzapride, which promote gastric emptying.
促动力药物可增加胃窦和肠道收缩，但通常不会增强排空，除非存在胃轻瘫。一种α2 - 肾上腺素能激动剂（SC - 39585A）被用于抑制犬的十二指肠运动并模拟胃轻瘫。SC - 39585A引起固体和液体食物排空以及对固体食物的胃窦和十二指肠运动反应的剂量相关性抑制。在非延迟条件下，促动力剂伦扎必利（100微克/千克静脉注射）并未增强固体食物的排空。然而，在相同剂量下，仅当SC - 39585A对十二指肠运动的抑制不完全（30微克/千克皮下注射）而非完全（100微克/千克皮下注射）时，它能部分逆转固体排空延迟。这部分是通过拮抗胃窦而非十二指肠的运动抑制来实现的。伦扎必利口服也能有效逆转固体排空延迟。同样，伦扎必利能逆转由SC - 39585A（30微克/千克皮下注射）引起的液体排空延迟。一种α2 - 肾上腺素能激动剂可通过抑制十二指肠运动来模拟犬的胃轻瘫，还可用于研究促进胃排空的运动兴奋剂（如伦扎必利）的作用。
