neurological control
Last reviewed 01/2018
- parasympathetic nerves (S2,3,4) initiate contraction of the bladder
- there is some sympathetic innervation of the trigone and the urethra (both alpha-contraction, and beta-relaxation)
- higher motor centres facilitate voluntary control of bladder emptying (centres in the pons, midbrain, posterior hypothalamus and ultimately in the frontal lobe of the cerebral cortex)
- cholinergic stimulation results in contraction of the detrusor muscle and trigone - this leads to an increased intravesical pressure and funnelling/shortening of the upper part of the urethra