Ageing in the hypothalamo-neurohypophysial-renal system.

Ageing is characterised by a failure in the maintenance of the internal environment (homeostasis) which is regulated by the hypothalamic neuroendocrine system. Of the many systems that undergo age-related degeneration is the control of water metabolism which leads to a variety of complications in the elderly. The magnocellular neurons of the hypothalamus produce the peptide anti-diuretic hormone (vasopressin) which acts on the kidney regulating water loss in the urine. This physiological axis lends itself to both fundamental studies of the cellular and molecular biology of ageing, and to studies of age-related alterations in the functional ability of elderly people. This review summarises some of the recent research into age-related changes in this system. The morphological and functional changes in the hypothalamus, neurohypophysis and kidney are described for the various species examined and the results discussed in terms of ageing in humans.