Changes in the Function and Expression of T-Type and N-Type Calcium Channels in the Rat Bladder after Bladder Outlet Obstruction

Purpose: We evaluated possible changes in the function and expression of T-type and N-type Ca2+ channels in the bladder of rats with bladder outlet obstruction.Materials and Methods: Female Sprague Dawley® rats were divided into a group with bladder outlet obstruction created by partial urethral ligation and a sham operated group. Six weeks postoperatively we determined the mRNA expression of T-type and N-type Ca2+ channels in the bladder, dorsal root ganglion and spinal cord. We also cystometrically investigated expression by intravenous administration of the T-Ca blocker RQ-00311610 or the N-type Ca2+ channel blocker ω-conotoxin GVIA. We then performed in vitro functional studies of detrusor strips using these blockers.Results: mRNA expression of T-type Ca2+ channels in the bladder detrusor and mucosa layers, and the spinal cord dorsal horn, and N-type Ca2+ channels in the whole bladder and detrusor layer, and the spinal cord dorsal horn was greater in the obstructed group than the sham operated group. ...