The circadian system modulates all visceral organ physiological processes including urine storage and voiding. The "master clock" of the circadian system lies within suprachiasmatic nucleus of the hypothalamus while "peripheral clocks" are found in most peripheral tissue and organs, including the urinary bladder. Disruptions of circadian rhythms can cause organ malfunction and disorder or exacerbate pre-existing ones. It has been suggested that
nocturia, which develops mostly in the elderly, could be a circadian-related disorder of the bladder. In the bladder, many types of gap junctions and
ion channels in the detrusor, urothelium and sensory nerves are likely under strict local peripheral circadian control. The pineal
hormone,
melatonin, is a circadian rhythm synchroniser capable of controlling a variety of physiological processes in the body.
Melatonin predominantly acts via the
melatonin 1 and
melatonin 2
G-protein coupled receptors expressed in the central nervous system, and many peripheral organs and tissues.
Melatonin could be beneficial in the treatment of
nocturia and other common bladder disorders. The ameliorating action of
melatonin on bladder function is likely due to multiple mechanisms which include central effects on voiding and peripheral effects on the detrusor and bladder afferents. More studies are warranted to determine the precise mechanisms of circadian rhythm coordination of the bladder function and
melatonin influences on the bladder in health and diseases.