title: Non-uniform changes in membrane receptors in the rat urinary bladder following outlet obstruction.
abstract: The aim of the present study was to investigate the expression and distribution of membrane receptors after bladder outlet obstruction (BOO). Partial bladder outlet obstruction (BOO) was induced in female rats and bladders were harvested after either 10 days or 6 weeks of BOO. The expression of different receptors was surveyed by microarrays and corroborated by immunohistochemistry and western blotting. A microarray experiment identified 10 membrane receptors that were differentially expressed compared to sham-operated rats including both upregulated and downregulated receptors. Four of these were selected for functional experiments on the basis of magnitude of change and relevance to bladder physiology. At 6 weeks of BOO, maximal contraction was reduced for neuromedin B and vasopressin (AVP), consistent with reductions of receptor mRNA levels. Glycine receptor-induced contraction on the other hand was increased and receptor mRNA expression was accordingly upregulated. Maximal relaxation by the β3-adrenergic receptor agonist CL316243 was reduced as was the receptor mRNA level. Immunohistochemistry supported reduced expression of neuromedin B receptors, V1a receptors and β3-adrenergic receptors, but glycine receptor expression appeared unchanged. Western blotting confirmed repression of V1a receptors and induction of glycine receptors in BOO. mRNA for vasopressin was detectable in the bladder, suggesting local AVP production. We conclude that changes in receptor expression following bladder outlet obstruction are non-uniform. Some receptors are upregulated, conferring increased responsiveness to agonist, whereas others are downregulated, leading to decreased agonist-induced responses. This study might help to select pharmacological agents that are effective in modulating lower urinary tract symptoms in BOO.
authors.affiliation: Department of Experimental Medical Science, BMC D12, Lund University, SE-221 84 Lund, Sweden; Department of Urology, Qing Yuan City People's Hospital, Jinan University, Guang Dong, China.
authors.forename: Jianwen
authors.initials: J
authors.lastname: Zeng
authors.affiliation: Department of Experimental Medical Science, BMC D12, Lund University, SE-221 84 Lund, Sweden.
authors.forename: Mari
authors.initials: M
authors.lastname: Ekman
authors.affiliation: Department of Urology, Qing Yuan City People's Hospital, Jinan University, Guang Dong, China.
authors.forename: Chonghe
authors.initials: C
authors.lastname: Jiang
authors.affiliation: Department of Urology, Clinical Sciences, Lund University, Lund, Sweden.
authors.forename: Bengt
authors.initials: B
authors.lastname: Uvelius
authors.affiliation: Department of Experimental Medical Science, BMC D12, Lund University, SE-221 84 Lund, Sweden. Electronic address: karl.sward@med.lu.se.
authors.forename: Karl
authors.initials: K
authors.lastname: Swärd
mesh_terms: D000818:Animals; D005260:Female; D005786:Gene Expression Regulation; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D021381:Protein Transport; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D001743:Urinary Bladder / Q000378:metabolism*; D001748:Urinary Bladder Neck Obstruction / Q000235:genetics / Q000378:metabolism*
chemical_list: D008565:Membrane Proteins; D012333:RNA, Messenger
keywords: AVP; Bladder outlet obstruction; Detrusor; Endothelin type A receptor; Glycine receptor; Lgr5; Lgr6; Membrane receptor; Neuromedin B receptor; P(2×5); Purinergic receptors; Tachykinin receptor 1; Thrombin receptor; V(1a) receptor; β(3)-Adrenoceptor