NKA enhances bladder afferent mechanosensitivity via urothelial and detrusor activation.

NKA enhances bladder afferent mechanosensitivity via urothelial and detrusor activation. Am J Physiol Renal Physiol. 2018 Jun 13;: Authors: Grundy L, Chess-Williams R, Brierley SM, Mills K, Moore KH, Mansfield K, Rose'Meyer R, Sellers DJ, Grundy D Abstract Tachykinins are expressed within bladder innervating sensory afferents and have been shown to generate detrusor contraction and trigger micturition. The release of tachykinins from these sensory afferents may also activate tachykinin receptors on the urothelium, or sensory afferents directly. Here we investigated the direct and indirect influence of tachykinins on mechanosensation by recording sensory signalling from the bladder during distension, urothelial transmitter release ex-vivo, and direct responses to NKA on isolated mouse urothelial cells and bladder-innervating DRG neurons. Bath application of NKA induced concentration-dependent increases in bladder afferent firing and intravesical pressure that were attenuated by nifedipine and by the NK2 receptor antagonist GR159897 (100nM). Intravesical NKA significantly decreased bladder compliance, but had no direct effect on mechanosensitivity to bladder distension (30µl/min). GR159897 alone enhanced bladder compliance, but had no effect on mechanosensation. Intravesical NKA enhanced both the amplitude and frequency of bladder micromotions during distension, which induced significant transient increases in afferent firing, and wer...
Source: Am J Physiol Renal P... - Category: Urology & Nephrology Authors: Tags: Am J Physiol Renal Physiol Source Type: research