Effect of thermal stress on serum prolactin, cortisol and plasma arginine vasopressin concentration in the pregnant and non-pregnant state.
The thermal responses of serum prolactin, cortisol and plasma arginine vasopressin were studied on pregnant and non-pregnant women. Group I consisted of 15 healthy non-pregnant women, group II of 23 women 13-14 weeks pregnant and group III of 23 women 36-37 weeks pregnant. Blood samples were taken before the stress (21-23 degrees C), at the end of a 20 min stay in a heat chamber (70 degrees C, 15% relative humidity) and 20 min and 45 min after the stress (21-23 degrees C). The rectal temperature increased 0.3-0.4 degrees C. Serum concentration of prolactin increased from the pre-stress level by 82% in group I (NS), by 25% in group II (P less than 0.05) by the end of the stress but declined steadily in group III by 12% till the end of the recovery period (P less than 0.001). The cortisol concentration increased only in group II during the recovery period (54-72%, P less than 0.05). In this group the subjects who felt discomfort after the stress had higher cortisol levels already before the stress. Arginine vasopressin levels increased significantly only in group I by 17% (P less than 0.05) and there were no differences in the proportional changes between the groups. The response of prolactin to thermal stress seems to be abolished at late pregnancy while the responses of cortisol and arginine vasopressin are not influenced by pregnancy.
Vähä-Eskeli
K
K
Department of Obstetrics & Gynecology, University of Turku, Finland.
Erkkola
R
R
Irjala
K
K
Viinamäki
O
O
D001127:Arginine Vasopressin / Q000097:blood*; D005260:Female; D006358:Hot Temperature / Q000009:adverse effects*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D008297:Male; D011247:Pregnancy / Q000097:blood*; D011261:Pregnancy Trimester, First; D011263:Pregnancy Trimester, Third; D011388:Prolactin / Q000097:blood*; D013997:Time Factors
D001127:Arginine Vasopressin; D011388:Prolactin; D006854:Hydrocortisone