CORTISOL IS NATRIURETIC IN THE IMMATURE OVINE FETUS.

in Journal of Endocrinology
Authors:
E.M. Wintour
Search for other papers by E.M. Wintour in
Current site
Google Scholar
PubMed
Close
,
J.P. Coghlan
Search for other papers by J.P. Coghlan in
Current site
Google Scholar
PubMed
Close
, and
M. Towstoless
Search for other papers by M. Towstoless in
Current site
Google Scholar
PubMed
Close
Restricted access
Rent on DeepDyve

Sign up for journal news

ABSTRACT

Cortisol was infused, intravenously, for 4 h continuously into 5 chronically cannulated ovine fetuses at 111-120 days of gestation (term is 142-152 days). The dose used was 100 μg/h, and raised fetal blood cortisol concentrations from 8.2±4.0 to 56.5±19.0 nmol/l (values are mean ± SEM). The effects observed were 1) a 4-5 fold increase in sodium and chloride excretion, 2) a doubling of potassium excretion and free water clearance, 3) no significant changes in urine pH, urea and creatinine excretions, and 4) an increase in urine osmolality from 129±7.5 to 154.4±11.3 mosmol/kg water. There were no significant changes in any of the measured parameters in 5 fetuses infused with 0.9% NaCl for 4 h. It is suggested that the hyponatremia and inability to retain sodium observed in many premature or very low birth weight babies may be due to the fact that their kidneys are behaving as fetal rather than neonatal organs and responding to the high plasma cortisol concentrations found in such babies with a natriuresis.

 

  • Collapse
  • Expand