TY - JOUR
T1 - Vasopressin and oxytocin excretion in the Brown-Norway rat in relation to aging, water metabolism and testosterone
AU - Goudsmit, E.
AU - Fliers, E.
AU - Swaab, D. F.
PY - 1988
Y1 - 1988
N2 - There is considerable disagreement in the literature on changes in the hypothalamo-neurohypophyseal system (HNS) with aging: some reports support HNS degeneration, whereas others claim an activation of this system in senescence. In order to study age-related changes in vasopressin (VP) and oxytocin (OT) excretion in relation to water metabolism, six young (4 months) and 12 aged (34 months) male Brown-Norway rats were placed in metabolism cages. Since plasma testosterone levels have been reported to affect HNS activity and to decline progressively with age, half of the aged animals were given subcutaneous testosterone implants. Urine volume and water intake were significantly increased in aged animals, while urine osmolality was significantly reduced. These changes could not be attributed to diminished VP secretion, since 24-h urinary excretion of this peptide was elevated in the aged animals. In addition, 24-h OT excretion was elevated in the aged animals, indicating an overall activation of the HNS in senescence. VP excretion was significantly correlated with urine osmolality, urine volume and urinary VP concentration. No significant differences were observed between testosterone- and sham-implanted aged rats. It is concluded that the moderate polyuria/polydipsia in the senescent Brown-Norway rat is probably due to renal changes and is accompanied by a compensatory rise in both VP and OT secretion. Testosterone does not affect these changes
AB - There is considerable disagreement in the literature on changes in the hypothalamo-neurohypophyseal system (HNS) with aging: some reports support HNS degeneration, whereas others claim an activation of this system in senescence. In order to study age-related changes in vasopressin (VP) and oxytocin (OT) excretion in relation to water metabolism, six young (4 months) and 12 aged (34 months) male Brown-Norway rats were placed in metabolism cages. Since plasma testosterone levels have been reported to affect HNS activity and to decline progressively with age, half of the aged animals were given subcutaneous testosterone implants. Urine volume and water intake were significantly increased in aged animals, while urine osmolality was significantly reduced. These changes could not be attributed to diminished VP secretion, since 24-h urinary excretion of this peptide was elevated in the aged animals. In addition, 24-h OT excretion was elevated in the aged animals, indicating an overall activation of the HNS in senescence. VP excretion was significantly correlated with urine osmolality, urine volume and urinary VP concentration. No significant differences were observed between testosterone- and sham-implanted aged rats. It is concluded that the moderate polyuria/polydipsia in the senescent Brown-Norway rat is probably due to renal changes and is accompanied by a compensatory rise in both VP and OT secretion. Testosterone does not affect these changes
U2 - https://doi.org/10.1016/0047-6374(88)90025-5
DO - https://doi.org/10.1016/0047-6374(88)90025-5
M3 - Article
C2 - 3216721
SN - 0047-6374
VL - 44
SP - 241
EP - 252
JO - Mechanisms of ageing and development
JF - Mechanisms of ageing and development
IS - 3
ER -