Influence of urothelial or suburothelial cholinergic receptors on bladder reflexes in chronic spinal cord injured cats.

Influence of urothelial or suburothelial cholinergic receptors on bladder reflexes in chronic spinal cord injured cats.
Exp Neurol. 2016 Nov;285(Pt B):147-158
Authors: Ungerer TD, Kim KA, Daugherty SL, Roppolo JR, Tai C, de Groat WC
Abstract
The effects of intravesical administration of a muscarinic receptor agonist (oxotremorine-M, OXO-M) and antagonist (atropine methyl nitrate, AMN) and of a nicotinic receptor agonist (nicotine) and antagonist (hexamethonium, C6) on reflex bladder activity were investigated in conscious female chronic spinal cord injured (SCI) cats using cystometry. OXO-M (50μM) decreased bladder capacity (BC) for triggering micturition contractions, increased maximal micturition pressure (MMP), increased frequency and area under the curve of pre-micturition contractions (PMC-AUC). Nicotine (250μM) decreased BC, increased MMP, but did not alter PMC-AUC. The effects of OXO-M on BC and PMC-AUC were suppressed by intravesical administration of AMN (50-100μM), and the effects of nicotine were blocked by hexamethonium (1mM). Antagonists infused intravesically alone did not alter reflex bladder activity. However, AMN (0.2mg/kg, subcutaneously) decreased PMC-AUC. 8-OH-DPAT (0.5mg/kg, s.c.), a 5-HT1A receptor agonist, suppressed the OXO-M-induced decrease in BC but not the enhancement of PMC-AUC. These results indicate that activation of cholinergic receptors located near the lumenal surface of the bladder modulates two...

Source: Experimental Neurology - October 26, 2016 Category: Neurology Authors: Ungerer TD, Kim KA, Daugherty SL, Roppolo JR, Tai C, de Groat WC Tags: Exp Neurol Source Type: research