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The activities of various enzymes involved in glycolysis, tricarboxylic acid cycle and fatty acid oxidation were assayed in human myometrium. A gradient of the activities from fundal to cervical myometrium was observed. In contrast to studies performed in rodents, cyclic changes of glycolytic enzymes could not be detected. Hydroxyacyl-CoA-dehydrogenase (HAD) activity was higher in secretory phase myometrium and in cases with cystic hyperplasia of the endometrium than in proliferative phase myometrium. In pregnant myometrium, lactate dehydrogenase (LDH) and glycogen phosphorylase (GLP) were increased and in postmenopausal myometrium the activities of phosphofructokinase (PFK), LDH and succinate dehydrogenase (SDH) were decreased as compared to proliferative phase myometrium. We conclude that in the human myometrium, except for HAD, activities of enzymes involved in fuel metabolism are stable throughout the menstrual cycle and that only prolonged hormonal stimulation leads to alterations of some enzyme activities.

The placenta and the fetal membranes differ in their energy dependent functions and in their blood supply. In a search for quantitative differences in the expression of enzymes involved in energy metabolism in these tissues we measured in the placenta and in amnion and chorion the activities of enzymes involved in carbohydrate metabolism (hexokinase, phosphofructokinase, lactate dehydrogenase, glycogen phosphorylase), a tricarboxylic acid cycle enzyme (succinate dehydrogenase) and an enzyme involved in fatty acid oxidation (hydroxyacyl-CoA-dehydrogenase). The activities of succinate dehydrogenase and hydroxyacyl-CoA-dehydrogenase in the placenta were higher than those in the membranes, whereas the activities of the other enzymes assayed were lower. Lactate dehydrogenase activity was higher in the amnion than in the chorion (p less than 0.01). These results could indicate that the fetal membranes depend mainly on glycolysis for an energy supply.

Am Modell der In-vitro-Perfusion des isolierten Kotyledo der menschlichen Plazenta am Termin wurde der Transfer von Acyclovir, einem gegen Herpes-simplex-Virus wirksamen Guaninderivat, gepruft. Die Plazentapassage von Acyclovir wurde mit dem Transfer von Substanzen verschiedener molekularer Struktur verglichen (Antipyrin, Kreatinin). Die Ergebnisse zeigen, das Acyclovir entsprechend seinem Molekulargewicht von 225 durch die menschliche Plazenta diffundiert. Damit sind therapeutisch wirksame Blutspiegel beim Fetus zu erwarten.