Inhibition of stress-induced gastric ulcers by sulphasalazine and its constituents (sulphapyridine and 5-aminosalicylic acid) in rats.
The effects of sulphasalazine and of its major constituents, sulphapyridine and 5-aminosalicylic acid (5-ASA), on gastric ulceration as well as on changes in mast cell counts and mucus levels in the glandular mucosa were examined in restrained rats exposed to 4 degrees C (stress) for 2 h. Sulphasalazine (50, 100, 200 mg/kg), sulphapyridine (31.25, 62.5, 125 mg/kg) or 5-ASA (18.75, 37.5, 75 mg/kg) was injected subcutaneously 0.5 h before stress induction. Cold-restraint stress produced gastric glandular mucosal ulcers which were significantly reduced by all three doses of sulphasalazine and the higher doses of sulphapyridine and 5-ASA. Sulphasalazine prevented mast cell degranulation and increased the amount of mucus adhering to the mucosa. In contrast, the higher doses of sulphapyridine significantly increased only the mucus levels, whereas those of 5-ASA effectively prevented mast cell degranulation. The results show that the total effect of sulphasalazine is approximately equivalent to the summation of the actions of its component doses of sulphapyridine and 5-ASA. It is notable that sulphapyridine itself appears to be biologically active in reducing ulcer severity.
Garg
G P
GP
Department of Pharmacology, Faculty of Medicine, University of Hong Kong.
Cho
C H
CH
Ogle
C W
CW
D000636:Aminosalicylic Acids / Q000627:therapeutic use*; D000818:Animals; D003080:Cold Temperature / Q000009:adverse effects*; D004338:Drug Combinations; D005260:Female; D019804:Mesalamine; D011292:Premedication; D051381:Rats; D011919:Rats, Inbred Strains; D013276:Stomach Ulcer / Q000209:etiology / Q000517:prevention & control*; D013312:Stress, Physiological / Q000150:complications*; D013427:Sulfapyridine / Q000627:therapeutic use*; D012460:Sulfasalazine / Q000627:therapeutic use*; D013997:Time Factors
D000636:Aminosalicylic Acids; D004338:Drug Combinations; D012460:Sulfasalazine; D019804:Mesalamine; D013427:Sulfapyridine