2. Change in Tissue Respiration of the Various Organs of the Rat in the Course of Normal Pregnancy, Parturition and Puerperium and That of the Placenta in Prolonged Pregnancy

Abstract

Oxygen consumptions of various organs were determined with a Warburg manometer in pregnancy, parturition and puerperium, and also that of the placenta in prolonged pregnancy induced by the administration of progesterone.1) Changes of Qo2 of the diencephalon, body of the uterus, thyroid, kidney, adrenal and placenta were statisticaly significant, but those of the ovary, fetal membrane, cervix of the uterus and liver were not significant.2) Qo2 of the diencephalon was elevated already on the 15th day of pregnancy, attaining the maximum on the 21st. It was decreased in parturition, later tended to decrease slightly, and approached the normal level on the 3rd puerperal day.3) Qo2 of the ovary did not show any significant change during the whole course, but tended to be higher on the 15th day of pregnancy and in puerperium, and lower in parturition.4) Qo2 of the body of the uterus was elevated already on the 15th day of pregnancy, remarkably elevated further on the 21st, lowered in parturition, and still more in puerperium, but remained on the same level with that on the 15th day.5) Qo2 of the cervix of the uterus did not change significantly, showing nearly the same tendency as that of the body of the uterus, except only that decrease in parturition was greater in the cervix than in the body.6) In parturition, Qo2 of the body of the uterus was remarkably higher than that of the cervix of the uterus.7) Oxgen consumption tended to show linear increase both in the body and the cervix of the uterus with progession from the normal period through pregnancy, parturition and puerperium.8) Qo2 of the placenta showed linear decrease with the advance of ppregnancy, and placental weight showed linear increase. Oxygen consumption per one placenta increased with the advance of pregnancy, but was lower in parturition than in later pregnancy. It was increased linearly on the 10th, 15th and 20th, but tended to decrease with the lapse of time in parturition.9) When pregnancy was prolonged by the injection of progesteron, Qo2 of the placenta on the 23rd of pregnancy was higher than in parturition and normal later pregnancy (on the 21st day). This was the same with oxygen consumption per one placenta, which continued linear increase in prolonged as in normal pregnancy.10) Qo2 of the fetal membrane did not show any significant change, exhibiting only slight tendency of decrease in parturition.11) Qo2 of the adrenal increased during pregnancy, attaining the maximum on the 21st day, decreased in parturition, again rose at 24 puerperal hours, and slightly lowered on the 3rd puerperal day.12) Qo2 of the thyroid on the 15th and 21st day of pregnancy showed gradual increase, but decreased in parturition, and in puerperium it was on the same level as on the 15th day pregnancy.13) Qo2 of the liver did not show significant difference between these stages, but tended to be lower from the 21st day of pregnancy, to hours post delivery, especially in parturition.14) Qo2 of the kidney significantly decreased during pregnancy. It still more decreased in parturition, and the some level as that in pregnancy was recovered in puerperium.