No abstract

The presence of myo‐inositol in adult and fetal tissues has been confirmed by crystallization, and determination of the molecular weight, melting point, percentage composition and chromatographic purity of the crystals. A pattern of distribution of myo‐inositol among the tissues of a given animal was observed; cerebellar and cortical tissue having the highest concentration and liver and skeletal muscle, the lowest. This pattern was found to be comparable in both adult and fetal tissues with the exception of cardiac muscle. Several species differences in distribution were noted.

Oxygen dissociation curves of the bloods of pregnant sheep, fetal and newborn lambs have been prepared at plasma hydrogen-ion concentrations in the physiological range. At pH 7 4, the fetal blood was half saturated at about 16-0 mm.Hg oxygen pressure. The maternal oxygen dissociation curves of the blood of different animals showed variability in their positions; half saturation occurred at values of oxygen pressure ranging from 316 to 37-5 mm. Hg. The curves of bloods of newborn lambs had positions intermediate between fetal and adult types.

By means of indwelling plastic catheters the pCO2, pH and bicarbonate levels of the maternal and fetal plasmas have been compared in sheep and goats by repeated sampling during periods up to 24 hr. Comparisons have been made in “steady state” conditions, as well as during and following NH4Cl infusion of the mother. The results demonstrate: (1) that the pCO2 of the blood of the umbilical artery is about 20 mm. Hg higher than the maternal arterial pCO2 in “steady state” conditions; (2) that this difference remains relatively stable despite wide variations in the pCO2 of the maternal arterial blood; (3) that the bicarbonate level of the fetal plasma is virtually independent of the maternal over a 24‐hr. period; and (4) in some circumstances the pH's of the maternal and fetal bloods may change in opposite directions.