Prostacyclin inhibits gastric emptying and small-intestinal transit in rats and dogs

摘要: Abstract Prostacyclin (PGI 2 ) antagonizes 16,16-dimethyl prostaglandin E -induced diarrhea in rats, presumably by inhibiting the fluid accumulation of "enteropooling" small intestine. The effect PGI on gastric emptying, intestinal transit, and colonic transit was examined rats dogs to determine if interference with propulsion might also contribute antidiarrheal properties this compound. Rats implanted chronic duodenal cannulas were given subcutaneous (0.1–1000 μg/kg) followed 10 min later intragastric 51 Cr a visually detectable marker. Forty-five minutes later, animals killed. Small-intestinal expressed as percentage length traveled detected Gastric emptying total found Subcutaneous inhibited maximally at μg/kg. significantly decreased 50 μg/kg almost completely suppressed 1.0 mg/kg. naloxone (0.5 mg/kg) before 20 after administration did not block 's effects. Intravenous or oral doses high 0.2 mg/kg, respectively, had none these However, high-dose intravenous bolus (1.0 infusion mg/kg · 45 min) both emptying. Small only infusion, suggesting that parameter more sensitive sustained blood level than Hourly injections no rat measured over 3-h period deposition marker through cannula manner similar described for small-intestinal above. barium suspension cannula. simultaneously received (10 an additional treatment abdominal x-ray every 30 thereafter. In vehicle-treated dogs, reached cecal area average 2.8 h instillation. -treated never cecum 5-h examination period. Thus, inhibits dog but has transit. These could activity.