Inhibition of Arachidonic Acid Release as the Mechanism by Which Glucocorticoids Inhibit Endotoxin‐induced Diarrhoea

Abstract

Dexamethasone blocked endotoxin‐induced diarrhoea in mice, but not that induced by arachidonic acid or prostaglandin E2. Indomethacin blocked endotoxin and arachidonic acid‐induced diarrhoea, but not that induced by prostaglandin E2. Codeine blocked all three forms of diarrhoea. The above data, when considered in relation to literature reports that endotoxin induces prostaglandin synthesis, suggest that dexamethasone blocks diarrhoea by preventing the release of arachidonic acid, the substrate for prostaglandin biosynthesis. The activities of indomethacin and dexamethasone in castor oil diarrhoea support the above conclusion and their inactivity in 5‐hydroxytryptophan‐induced diarrhoea confirms the absence of ‘codeine‐like’ direct effects on the gut. Other glucocorticoids (hydrocortisone, prednisolone) were also able to block endotoxin diarrhoea, but oestradiol, testosterone and progesterone did not. The inhibitory action of dexamethasone on endotoxin diarrhoea could not be blocked by the protein synthesis inhibitor, cycloheximide, nor by the glucocorticoid receptor antagonist, progesterone. Thus, involvement of glucocorticoid receptor‐mediated gene activation could not be demonstrated.

Antioxidant, antidiarrhoeal and cytotoxic properties of aerial parts of Trichosanthes dioica Roxb.

“…to the control group, Loperamide (3 mg/kg, p.o.) to the positive control group, the petroleum ether, ethyl acetate, methanol and water extracts at the doses of 200 and 400 mg/kg to the test groups (Doherty, 1981). The observations were made for 4 h and total numbers of diarrhoeal droppings were recorded.…”

Antinociceptive, antidiarrheal, and neuropharmacological activities ofBarringtonia acutangula

“…The experiment was carried out according to the method described by Doherty (1981). Diarrhea was induced by oral administration of magnesium sulphate at the dose of 2 g/kg.…”

Central Nervous System Depressant, Analgesic and Antidiarrheal Effects of the Seed Extracts of <i>Dimocarpus longan</i> Lour in Rats

“…Awouter et al [21] method was used for this test. Fifty rats were fasted for 18 h with free access to water and randomly separated into ten groups of five rodents each.…”