STUDIES ON OXYTOCIN IN THE BABOON DURING PREGNANCY AND DELIVERY
| Autor: | Fritz Fuchs, M Y Dawood, Olavi Ylikorkala, N H Lauersen, D Trivedi |
|---|---|
| Rok vydání: | 1979 |
| Předmět: |
endocrine system
medicine.medical_specialty Amniotic fluid Endocrinology Diabetes and Metabolism Oxytocin Uterine contraction Uterine Contraction Endocrinology Pregnancy Placenta Internal medicine biology.animal medicine Animals Infusions Parenteral Maternal-Fetal Exchange Fetus Labor Obstetric biology business.industry Haplorhini General Medicine Amniotic Fluid Fetal Blood medicine.disease medicine.anatomical_structure Pituitary Gland embryonic structures Pregnancy Animal Gestation Female medicine.symptom business hormones hormone substitutes and hormone antagonists Half-Life Papio medicine.drug Baboon |
| Zdroj: | Acta Endocrinologica. 91:704-718 |
| ISSN: | 1479-683X 0804-4643 |
| Popis: | Oxytocin was determined by radioimmunoassay in pregnant baboons throughout gestation, in the foetus at caesarean section, and after oxytocin infusion into the mother and foetus. Serial maternal plasma oxytocin in 6 baboons during pregnancy showed a significant correlation between the gestational age and maternal plasma oxytocin concentrations with a correlation coefficient of r = 0.3185 and P < 0.005. Seventy-one out of 75 plasma samples (94.7 %) during pregnancy had detectable levels of oxytocin. Uterine vein plasma had higher oxytocin concentrations than maternal plasma and amniotic fluid (18.6 ± 4.6 pg/ml; mean ± se) but lower than umbilical, jugular vein and cardiac blood from the foetus. Foetal pituitary gland contained 5.4–26.1 μg oxytocin/g. Regular uterine contractions were established with iv oxytocin of 4–20 mU/min and the plasma oxytocin measured showed a significant correlation with the uterine activity achieved (r = 0.64, P < 0.001). The disappearance of plasma oxytocin at 179 days gestation gave an apparent half-life of 1.1 and 1.7 min in 2 baboons with a late half-life of 9.9 and 17.3 min, respectively. In one baboon at 171 days gestation, the apparent half-life of oxytocin was 9.9 min. The metabolic clearance rates were calculated to be 3.1, 3.2 and 11.7 ml/kg/min, respectively. The production rates were 97, 74, 390 pg/kg/min, respectively. Oxytocin injected into the umbilical vessel near term showed an increase in oxytocin concentration in maternal and uterine vein plasma and amniotic fluid, suggesting that oxytocin can cross the placenta from the foetal to the maternal side. Our findings indicate that in the baboon (1) oxytocin is present throughout pregnancy, (2) uterine activity can be correlated with plasma oxytocin during oxytocin infusion, (3) foetal circulation has higher oxytocin concentration than maternal blood and (4) oxytocin probably can cross the placenta from the foetus to the mother. |
| Databáze: | OpenAIRE |
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