Maternal and Fetal Blood Ammonia Concentrations in Normal Term Human Pregnancies
| Autor: | Michał Jóźwik, Cecilia Teng, Bartosz Pietrzycki, Marcin Chojnowski, Frederick C. Battaglia, Maciej Jóźwik, Marcin Jóźwik |
|---|---|
| Rok vydání: | 2005 |
| Předmět: |
Adult
Umbilical Veins medicine.medical_specialty Physiology Gestational Age Biology Umbilical Arteries Ammonia production Species Specificity Blood concentration Ammonia Pregnancy Reference Values Fetal membrane Placenta medicine Animals Humans Neonatology Fetus Sheep Obstetrics Term pregnancy Infant Newborn Fetal Blood medicine.anatomical_structure Pediatrics Perinatology and Child Health Female Blood ammonia Developmental Biology |
| Zdroj: | Neonatology. 87:38-43 |
| ISSN: | 1661-7819 1661-7800 |
| Popis: | Background: The current evidence on the primary source of ammonia production in the human fetoplacental unit is potentially misleading. Objective: The aim of the present investigation was to determine the concentration of ammonia in human maternal and fetal blood at birth and to compare them with published data in late gestation sheep. Methods: In 12 normal human pregnancies, umbilical arterial and venous and maternal venous blood was sampled, and whole blood ammonia concentrations were measured. Data from 12 pregnant sheep and fetuses from our previous studies were utilized for comparison. Results: The human fetus at delivery has higher concentrations of ammonia (60–80 µM) than the late gestation fetal lamb (25–35 µM). In the human, the arterial umbilical ammonia concentration exceeds the venous umbilical concentration, indicating a net ammonia production by fetal tissues. In sheep, the venous umbilical ammonia concentration exceeds the arterial umbilical concentration, indicating the net placental ammonia production. Conclusions: In contrast to fetal lambs, human fetuses exhibit a net production of ammonia, which may reflect differences in biologic state or a species difference. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|