Studies on the expression and function of beta-3-adrenoceptors in the colon of rats with acetic acid-induced colitis.
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.
Khan
Islam
I
Department of Biochemistry, Faculty of Medicine, Kuwait University, Safat 13110, Kuwait.
Hussein
Shaima M K
SM
Oriowo
Mabayoje  A
M
D019342:Acetic Acid / Q000494:pharmacology; D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D003093:Colitis, Ulcerative / Q000139:chemically induced / Q000235:genetics / Q000503:physiopathology*; D003106:Colon / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D004305:Dose-Response Relationship, Drug; D004983:Ethanolamines / Q000037:antagonists & inhibitors / Q000494:pharmacology; D005260:Female; D007545:Isoproterenol / Q000494:pharmacology; D009126:Muscle Relaxation / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects / Q000503:physiopathology; D009195:Peroxidase / Q000378:metabolism; D010869:Pindolol / Q000031:analogs & derivatives* / Q000494:pharmacology; D011189:Potassium Chloride / Q000494:pharmacology; D012333:RNA, Messenger / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D022702:Receptors, Adrenergic, beta-3 / Q000187:drug effects / Q000235:genetics / Q000502:physiology*
D000318:Adrenergic beta-Agonists; D000319:Adrenergic beta-Antagonists; D004983:Ethanolamines; D012333:RNA, Messenger; D022702:Receptors, Adrenergic, beta-3; C047975:cyanopindolol; C057368:BRL 37344; D011189:Potassium Chloride; D010869:Pindolol; D009195:Peroxidase; D007545:Isoproterenol; D019342:Acetic Acid