FOETAL AND MATERNAL CORTISOL AND PROGESTERONE AND MATERNAL OESTRADIOL IN PROLONGED PREGNANCY AFTER FOETAL HYPOPHYSECTOMY IN SHEEP

in Journal of Endocrinology
Authors:
J. S. ROBINSON
Search for other papers by J. S. ROBINSON in
Current site
Google Scholar
PubMed
Close
,
J. R. G. CHALLIS
Search for other papers by J. R. G. CHALLIS in
Current site
Google Scholar
PubMed
Close
,
G. POOLEY
Search for other papers by G. POOLEY in
Current site
Google Scholar
PubMed
Close
, and
G. D. THORBURN
Search for other papers by G. D. THORBURN in
Current site
Google Scholar
PubMed
Close
Restricted access
Rent on DeepDyve

Sign up for journal news

John Radcliffe Hospital and Nuffield Institute for Medical Research, Headley Way, Headington, Oxford, 0X3 9DU

(Received 1 September 1976)

Liggins, Fairclough, Grieves, Kendall & Knox (1973) drew attention to the role of the foetal pituitary-adrenal system in the initiation of parturition in sheep by demonstrating prolonged pregnancy after foetal hypophysectomy and premature delivery after intra-foetal infusion of glucocorticoid or synthetic corticotrophin (ACTH). Bassett & Thorburn (1969) observed a rise of foetal cortisol before spontaneous parturition in this species. The increasing foetal cortisol induces the decline in maternal plasma progesterone observed in the last 10-15 days of pregnancy and the oestradiol increase in the last 24 h before delivery (see Thorburn, Challis & Robinson, 1976). In naturally occurring prolonged pregnancy in cows (Holm & Short, 1962) and sheep (Basson, Morgenthal, Bilbrough, Marais, Kruger & van der Merwe, 1969) the concentration of progesterone in maternal plasma remains raised after normal term. Similarly,

 

  • Collapse
  • Expand