Dysfunctions of the lower urinary tract are the product of storage failure. Spontaneous regional bladder wall movements (nonmicturition contractions, NMCs) are proposed to generate afferent activity that signals volume status to the central nervous system. The sympathetic nervous system, via activation of β-adrenoceptors (β-AR), causes bladder relaxation and promotes urine storage. It is hypothesized that β-AR regulation of micturition is mediated by suppression of NMCs. In an unanesthetized decerebrate rat preparation, systemic isoprenaline increased intervoid interval and bladder compliance accompanied by a decrease in NMC amplitude, voiding pressure, and voiding threshold. Isoprenaline also reduced arterial pressure and increased heart rate. The β3-AR agonist mirabegron selectively increased intervoid interval and bladder compliance and reduced NMC amplitude yet preserved active voiding function with no cardiovascular effects.
See article at J Pharmacol Exp Ther 2013, 347:506–515.
- Copyright © 2013 by The American Society for Pharmacology and Experimental Therapeutics