Aging increases the expression of vasopressin receptors in both the kidney and urinary bladder

Abstract

Aims: The goal of this study was to determine whether aging effects the expression of V 1a and V 2 vasopressin receptors in the urinary bladder mucosa (UBM) and kidney. Methods: UBM and kidneys were obtained from young (3 months-of-age) and old (25-30 months-of-age) female Fisher 344 rats. Tissue samples were analyzed by western blotting for V 1a and V 2 receptor expression, and rat plasma levels of vasopressin levels were measured by ELISA. Results: V 1a and V 2 receptors were detected in both the UBM and kidneys. Aging significantly (P < 0.05) increased the expression of V 2 receptors by 2.80 ± 0.52 and Neurourology and Urodynamics. 2019;38:393-397.wileyonlinelibrary.com/journal/nau

Intrarenal Renin–Angiotensin System Involvement in the Pathogenesis of Chronic Progressive Nephropathy—Bridging the Informational Gap Between Disciplines

“…60 The RAS is altered during aging, with reduced plasma renin activity (PRA) and decreased aldosterone levels, partially compensated for by increases in the density of AngII and vasopressin receptors in aging rats and in older human patients. 61 –65 Despite the decline in RAS activity with age, local renal secretion of AngII is markedly increased and responsiveness to AngII is enhanced. 66 –68 Recent work in the field of CKD in humans has focused on one arm of this axis, the intrarenal renin–angiotensin system (IRAS).…”

Pathophysiological Mechanisms of Nocturia and Nocturnal Polyuria: The Contribution of Cellular Function, the Urinary Bladder Urothelium, and Circadian Rhythm

“…[22][23][24] Urothelium expresses both V 1a and V 2 receptors and, in aging animals, V 2 receptor expression in the UT and kidneys and V 1a receptor expression in the kidneys increase, suggesting that the UT is an active participant in water homeostasis, particularly during old age. 25 Consequently, desmopressin treatment for nocturia due to NP may be particularly effective in elderly people, in whom there is increased expression of the V 2 receptor (the intended target for desmopressin) in both the bladder UT and the kidney. 25 The expression of V 1a , V 1b , and V 2 AVP receptor subtypes in the urinary bladder suggest that AVP may be involved in modulating bladder smooth muscle tone through the regulation of intravesical pressure.…”

“…25 Consequently, desmopressin treatment for nocturia due to NP may be particularly effective in elderly people, in whom there is increased expression of the V 2 receptor (the intended target for desmopressin) in both the bladder UT and the kidney. 25 The expression of V 1a , V 1b , and V 2 AVP receptor subtypes in the urinary bladder suggest that AVP may be involved in modulating bladder smooth muscle tone through the regulation of intravesical pressure. Intravenous or in situ AVP evokes a huge increase in intravesical pressure due to binding in V 1a or V 2 receptors localized in the bladder.…”

Re: Birder LA, Wolf‐Johnston AS, Jackson EK, Wein AJ, Dmochowski R. Aging increases the expression of vasopressin receptors in both the kidney and urinary bladder. Neurourol Urodyn. 2019 Jan;38(1):393–397

“…The authors are to be congratulated on their important paper "Aging increases the expression of vasopressin receptors (VRs) in both the kidney and urinary bladder" that provides solid evidence for their speculation that the urinary bladder mucosa may be an additional site for vasopressin action. 1 Their speculation is supported by our recurring and yet unexplained clinical observation, that predominantly older patients develop polyuria, primarily at night, following urinary undiversion. We have observed the same phenomen in patients with continuous bladder drainage either by indwelling transurethral catheters or by suprapubic tubes.…”

“…The authors are to be congratulated on their important paper “Aging increases the expression of vasopressin receptors (VRs) in both the kidney and urinary bladder” that provides solid evidence for their speculation that the urinary bladder mucosa may be an additional site for vasopressin action …”