A better understanding of basic science may help our management of LUTS/LUTD in older persons with nocturnal polyuria and nocturia: ICI-RS 2024.

Aims: To discuss the role of autocrine/paracrine signaling of urothelial arginine vasopressin (AVP) on mammalian bladder capacities and micturition thresholds, impact of distension on water/urea reabsorption from the bladder, review of the literature to better characterize the central/peripheral effects of AVP, desmopressin (dAVP) toxicity, and urine biomarkers of nocturia.

Methods: This review summarizes discussions during an International Consultation on Incontinence-Research Society 2024 think tank with respect to the role of urothelial AVP in aged individuals with nocturnal polyuria, impact of solute and water reabsorption by the bladder on uninterrupted sleep, central effects of AVP, pharmacological basis of dAVP toxicity, and biomarkers in nocturia/lower urinary tract dysfunction (LUTD) with neurological diseases.

Results: Consensus recognized AVP function and pathways in the central nervous system (CNS), pre-proAVP localized using immunohistochemistry in bladder sections from adult/aged noncancerous human punch biopsies and rodent bladder sections is likely to accelerate the systemic uptake of water and urea from the bladder of anesthetized mice instilled with ³H-water and ¹⁴C-urea. Mechanisms for charged and uncharged solutes and water transport across the bladder, mechanism of dAVP toxicity, and utility of urine biomarkers in those with neurological diseases/nocturia were determined from literature reviews.

Conclusion: Pre-proAVP is present in human/rodent bladders and may be involved in water reabsorption from bladder that prevents the sensation of fullness for uninterrupted sleep in healthy adults. The mechanism of action of AVP in the CNS was discussed, as was electrolyte/water transport across the bladder, the basis for dAVP toxicity, and feasibility of urine biomarkers to identify nocturia/LUTD with neurological diseases.