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Biomedical subjects

H Morikawa

Publications and source records attributed to H Morikawa.

14 recordsLinked to original sources
PubMed1992

[A trial of low-dose aspirin therapy in high-risk pregnancy].

Intra-uterine growth retardation, intra-uterine fetal death and pre-eclampsia have common abnormalities: A reduction of uteroplacental perfusion, lack of vasodilation of spiral arteries and subsequent thrombosis. These physiological processes have been explained by an imbalance between prostacyclin and thromboxane A2 production. Many studies have suggested that treatment with low-dose aspirin and steroids is effective in preventing pregnancy loss or pre-eclampsia, but the mechanism has not been established. We evaluated the effectiveness of these therapies in patients at risk for pregnancy loss with the aspect of intracellular ionized calcium mobilization. Low-dose aspirin directs the prostacyclin/thromboxane A2 balance to the dominance of prostacyclin and steroids suppress the activities of lupus anticoagulant or antiphospholipid antibodies. The intracellular ionized calcium concentration in platelets is decreased significantly after these therapies. Concerning the pathological examination of placenta, there were deposits of fibrin in only 2 out of 8 cases and there were no abnormal findings in the other 6 cases. These data show that the aggregation of platelets is suppressed in microvascular circulations. These therapies do not cause any adverse effect on the mother or fetus. It is concluded that low-dose aspirin therapy with steroids is useful for patients with a poor obstetrical history.

6-Ketoprostaglandin F1 alpha↗
PubMed1978

A study on the effect of dehydroepiandrosterone sulfate on so-called cervical ripening.

Dehydroepiandrosterone sulfate (DHAS) is now used for a dynamic test of placental function by many obstetricians. While practicing this test, the authors found that DHAS markedly promoted so-called "cervical ripening". To study this problem, DHAS of 50 or 100 mg in multiple doses were injected into 132 Japanese pregnant women in their 38th--42nd week of gestation. The change in Bishop score was carefully recorded. Bishop score in the injected groups of primiparae (100 mg) began to rise much sooner than the control groups (p less than 0.01 on seventh day and 14th day). However, such significant difference in the rise of Bishop score was not noted in the multiparae and primiparae with 50 mg. Although the rise of score is not significant, the duration (day) from injection to delivery was shorter in the injected group than the control group (t=2.1529, p less than 0.05 in primiparae with 50 mg, t=3.8829, p less than 0.01 with 100 mg, t=2.1029, p less than 0.05 in multiparae with 50 mg). In some of these cases, labor began or delivery was finished within 24 hrs. Among the factors of Bishop score, mainly the effacement, consistency and dilatation of the cervix were remarkably improved by DHAS injection (p less than 0.01 and less than 0.05). Side effects of any type were not seen in the mothers and foetuses. As a conclusion, DHAS injection in considered to produce favorable conditions for delivery in women with "unripe cervix" by softening the soft birth canal. Furthermore, it is suggested that DHAS might play an important role in triggering labor.

Cervix Uteri↗
PubMed1977

A morphological and physiological study of mesotubarium ovarica in humans.

In order to clarify the mechanisms by which the egg is transported from the ruptured follicle into the fimbrial end of the Fallopian tube in the human being, the mesotubarium ovarica (MTO), the unique anatomical structure which connects the tubal fimbriae and the ovary, was studied in seven human adnexal specimens histochemically and electron microscopically. The results demonstrated clearly the presence of smooth muscle cells in the MTO, and failed to demonstrate the presence of cilia in the lining epithelial cells of the MTO. Based on these morphological results, contractility of the MTO was studied in vitro by using a muscle chamber and a pressure transducer with 26 human adnexal specimens. Spontaneous contractile activites of regular frequency and moderate intensity were observed in the MTOs of all specimens examined. A possible role of the MTO in the mechanisms of ovum pickup at the time of ovulation is discussed.

Adult↗
PubMed1977

A morphologic study of mesotubarium ovarica in the human.

In order to clarify the mechanisms by which the egg is transported from the ruptured follicle into the fimbrial end of the fallopian tube in the human, the mesotubarium ovarica (MTO), the unique anatomic structure which connects the tubal fimbriae and the ovary, was studied in seven human adnexal specimens histochemically and electronmicroscopically. The results demonstrated clearly the presence of smooth muscle cells in the MTO, and failed to demonstrate the presence of cilia in the lining epithelial cells of the MTO. A possible role of the MTO in the mechanisms of ovum pick-up at the time of ovulation is discussed.

Adult↗
PubMed1976

An enzymologic study of corpora lutea in early pregnant rats treated with abortifacient agents.

Luteal metabolism was investigated in corpora lutea of early pregnant rats treated with four abortifacient agents. In corpora lutea of rats treated with prostaglandin F2alpha or of rats 1 day postpartum, glucose-6-phosphate dehydrogenase (G6PDH) activity increased 140 to 170% and 20alpha-hydroxysteroid dehydrogenase (20alpha-HSD) was activated to significantly high levels, whereas malic enzyme activity decreased to 29% of control values. In aminoglutethimide-treated rats, the activities of G6PDH and malic enzyme decreased, while 20alpha-HSD activity was maintained at a very low level. With the increased dose, complete abortion was observed. In corpora lutea of these aborted rats, 20alpha-HSD was activated moderately and G6PDH values were slightly higher than control values, whereas malic enzyme activity fell to lower levels. All rats treated with clomiphene citrate aborted within 63 hours after the last injection. The activities of G6PDH, malic enzyme, and ATP citrate lyase in these corpora lutea decreased to 66, 68, and 72% of control levels, respectively; 20alpha-HSD activity was maintained at a very low level, and activities of 3beta-hydroxysteroid dehydrogenase, 6-phosphogluconate dehydrogenase, and pyruvate kinase were not appreciably altered. These findings indicated that, at the beginning of luteolysis and fetal resorption, the activities of steroidogenic enzymes decreased and 20alpha-HSD was not yet activated. Therefore, we could gauge the early changes of luteolysis by measuring the activities of G6PDH, MALIC ENZYME, AND ATP citrate lyase as well as 20alpha-HSD.

ATP Citrate (pro-S)-Lyase↗
PubMed1976

Growth hormone, prolactin and chorionic somatomammotropin in normal and molar pregnancy.

Twenty patients with molar pregnancy, ten normal pregnant women and ten healthy non-pregnant women were given 30 g of arginine intravenously. The serum concentration of growth hormone, prolactin and chorionic somatomammotropin (CS) was determined by radioimmunoassay. In addition, serum 17beta-estradiol, estriol and progesterone were also measured. Arginine infusion induced a sharp rise of GH in patients with molar pregnancy and in nonpregnant subjects, but the response in normal pregnancy was blunted. The response of PRL was high in patients with molar pregnancy, blunted in normal pregnancy and very small in nonpregnant subjects. CS did not respond at all to arginine infusion both in normal pregnancy and molar pregnancy. The high response to argine of PRL, normal response of GH and low baseline secretion and no response of CS may be characteristic of molar pregnancy.

Arginine↗
PubMed1975

Lipolytic action of human chorionic somatomammotropin.

Human chorionic somatomammotropin extracted and purified from placenta at term was proved to have a lipolytic action in the epididymal fat pad of rats. The following mechanism appears to be involved in the lipolytic action of the hormone; human chorionic somatomammotropin activates adenyl cyclase, thereby increasing the concentration of cyclic AMP in the tissue, which, in turn, activates protein kinase to lead to the activation of hormone sensitive lipase.

Adenylyl Cyclases↗