title: Increased expression of 5-HT(2A) and 5-HT(2B) receptors in detrusor muscle after partial bladder outlet obstruction in rats.
abstract: Serotonin (5-hydroxytryptamine; 5-HT)-induced bladder contraction is enhanced after partial bladder outlet obstruction (pBOO) in rats. We investigated time-dependent changes in bladder contraction and expression of 5-HT(2A) and 5-HT(2B) receptor mRNA in bladder tissue to elucidate the mechanism of this enhancement. On day 3 and 7 after pBOO, contractile responses of isolated rat bladder strips to 5-HT were increased compared with that in sham-operated rats; on day 14, the response had decreased to the same level as that in sham rat bladders. In contrast, carbacholinduced contraction was not enhanced by pBOO at any time point. In sham rats, 5-HT(2A) receptor mRNA was expressed in the urothelium, and 5-HT(2B) receptor mRNA was expressed in the detrusor muscle layer. In pBOO rats, both receptor mRNAs were increased in the detrusor muscle and subserosal layers, but not in the urothelium. The increase of 5-HT(2A) receptor mRNA was maintained from day 3 to day 14 after pBOO, and 5-HT(2B) receptor mRNA was increased on day 7 after pBOO. These results suggested that pBOO induced up-regulation of the 5-HT(2A) and 5-HT(2B) receptors in the detrusor muscle and subserosal layers of the bladder, and such up-regulation may be related to the enhanced bladder contractile response to 5-HT.
authors.affiliation: Laboratory for Pharmacology, Pharmaceuticals Research Center, Asahi Kasei Pharma Corporation.
authors.forename: Mai
authors.initials: M
authors.lastname: Michishita
authors.forename: Kazuo
authors.initials: K
authors.lastname: Yano
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Kasahara
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Tomita
authors.forename: Osamu
authors.initials: O
authors.lastname: Matsuzaki
mesh_terms: D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D015870:Gene Expression; D017403:In Situ Hybridization; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D044402:Receptor, Serotonin, 5-HT2A / Q000235:genetics* / Q000378:metabolism; D044403:Receptor, Serotonin, 5-HT2B / Q000235:genetics* / Q000378:metabolism; D012701:Serotonin / Q000494:pharmacology; D001748:Urinary Bladder Neck Obstruction / Q000235:genetics* / Q000378:metabolism
chemical_list: D012333:RNA, Messenger; D044402:Receptor, Serotonin, 5-HT2A; D044403:Receptor, Serotonin, 5-HT2B; D012701:Serotonin