Prostacyclin inhibits gastric emptying and small-intestinal transit in rats and dogs
Prostacyclin (PGI2) antagonizes 16,16-dimethyl prostaglandin E2-induced diarrhea in rats, presumably by inhibiting the fluid accumulation of ''enteropooling'' in the small intestine. The effect of PGI2 on gastric emptying, small intestinal transit, and colonic transit was examined in rats and dogs to determine if interference with propulsion might also contribute to the antidiarrheal properties of this compound. Rats implanted with chronic duodenal cannulas were given subcutaneous PGI2 (0.1-1000 microgram/kg) followed 10 min later by intragastric /sup 2/Cr and a visually detectable duodenal transit marker. Forty-five minutes later, the animals were killed. Subcutaneous PGI2 inhibited gastric emptying maximally at 10 micrograms/kg. Small-intestinal transit was significantly decreased at 50 micrograms/kg and almost completely suppressed at 1.0 mg/kg. Subcutaneous naloxone (0.5 mg/kg) given 10 min before and 20 min after subcutaneous PGI2 administration did not block PGI2's effects. Intravenous or oral PGI2, had none of these effects. Small intestinal transit was only decreased by PGI2 infusion, suggesting that this parameter was more sensitive to a sustained blood level than gastric emptying. Hourly injections of subcutaneous PGI2 (0.5 mg/kg) had no effect on rat colonic transit measured over a 3-h period after deposition of the transit marker through a colonic cannula in a manner similar to that described for small-intestinal transit above. Small-intestinal transit was also measured in dogs given a barium suspension through a chronic duodenal cannula. In vehicle-treated dogs, barium reached the cecal area in an average of 2.8 h after instillation. In PGI2-treated dogs, barium never reached the cecum in the 5-h examination period. Thus, PGI2 inhibits gastric emptying in rat and small-intestinal transit in rat and dog but has no effect on rat colonic transit.
- Research Organization:
- UpJohn Co., Kalamazoo, MI
- OSTI ID:
- 6410371
- Journal Information:
- Gastroenterology; (United States), Vol. 87:2
- Country of Publication:
- United States
- Language:
- English
Similar Records
Biphasic effect of duodenal ulcerogens cysteamine (C), mepirizole (M) and 1-methyl-4-phenyl-1,2,3,6-tetrahydropryridine (MPTP) on gastric emptying in the rat
Impaired transit of chyme in chronic intestinal pseudoobstruction. Correction by cisapride
Related Subjects
59 BASIC BIOLOGICAL SCIENCES
PROSTAGLANDINS
BIOLOGICAL EFFECTS
SMALL INTESTINE
BIOLOGICAL FUNCTIONS
BIOMEDICAL RADIOGRAPHY
CHROMIUM 51
DIARRHEA
DOGS
RATS
TRACER TECHNIQUES
X RADIATION
ANIMALS
BETA DECAY RADIOISOTOPES
BODY
CHROMIUM ISOTOPES
DIAGNOSTIC TECHNIQUES
DIGESTIVE SYSTEM
ELECTROMAGNETIC RADIATION
ELECTRON CAPTURE RADIOISOTOPES
EVEN-ODD NUCLEI
FUNCTIONS
GASTROINTESTINAL TRACT
INTERMEDIATE MASS NUCLEI
INTESTINES
IONIZING RADIATIONS
ISOTOPE APPLICATIONS
ISOTOPES
MAMMALS
MEDICINE
NUCLEAR MEDICINE
NUCLEI
ORGANS
RADIATIONS
RADIOISOTOPES
RADIOLOGY
RODENTS
SYMPTOMS
VERTEBRATES
560305* - Chemicals Metabolism & Toxicology- Vertebrates- (-1987)
551001 - Physiological Systems- Tracer Techniques