brl-37344 and Colitis--Ulcerative

Ulcerative colitis is characterized by dysfunctional motility. Our main objective in this investigation was to study the effect of an acetic acid-induced ulcerative colitis on the expression and function of beta(3)-adrenoceptors in the rat colon. Inflammation was induced by administering acetic acid intrarectally into rats. Levels of myeloperoxidase activity and beta(3)-adrenoceptor mRNA were measured in colon samples taken following acetic acid administration. Relaxation responses to beta(3)-adrenoceptor agonists were also studied. Ulcerative colitis was associated with significantly elevated levels of myeloperoxidase activity in the colon segments. Levels of beta(3)-adrenoceptor mRNA as well as the relaxation responses to isoprenaline and BRL 37344 were however not significantly different between inflamed and control tissue. Acetic acid-induced ulcerative colitis in rats was not associated with changes in the expression and/or function of beta(3)-adrenoceptors in the rat colon. Therefore, the dysfunctional motility that is characteristic of ulcerative colitis, is not likely to be due to changes in beta(3)-adrenergic mechanisms in this model.

Topics: Acetic Acid; Adrenergic beta-Agonists; Adrenergic beta-Antagonists; Animals; Colitis, Ulcerative; Colon; Dose-Response Relationship, Drug; Ethanolamines; Female; Isoproterenol; Muscle Relaxation; Muscle, Smooth; Peroxidase; Pindolol; Potassium Chloride; Rats; Rats, Sprague-Dawley; Receptors, Adrenergic, beta-3; RNA, Messenger