Two-step inhibitory effect of kanzo on oxytocin-induced and prostaglandin F2α-induced uterine myometrial contractions.

We previously reported that shakuyaku-kanzo-to, a kampo medicine consisting of shakuyaku and kanzo, has an inhibitory effect on myometrial contractions in pregnant women. In this study, we evaluated the effects of kanzo, glycyrrhizin (a major component of kanzo), glycyrrhetinic acid (GA; a major metabolite of glycyrrhizin), shakuyaku, and paeoniflorin (a major component of shakuyaku) on agonist-induced contractions of the uterus of pregnant humans and rats. We prepared myometrial strips from the uterus of pregnant humans and rats and induced contractions with oxytocin (50 µU/mL) or prostaglandin F2α (PGF2α) (10(-7) or 10(-6) M). Kanzo (250 µg/mL) and GA (5 × 10(-6) M) inhibited the oxytocin-induced and PGF2α-induced contractions in pregnant human and rat myometrium, but shakuyaku (250 µg/mL), paeoniflorin (10(-5) M), and glycyrrhizin (10(-5) M) did not inhibit contractions in either. Interestingly, kanzo and GA showed an inhibitory effect after temporarily enhancing the PGF2α-induced contractions in the rat myometrium, but not in the human myometrium. These results suggest that kanzo has at least a two-step inhibitory effect on the myometrial contractions that originate from the kanzo itself and a metabolite of glycyrrhizin in kanzo. Furthermore, kanzo was found to be safe for inhibiting PGF2α-induced contractions in humans because it did not temporarily enhance PGF2α-induced contractions.

A placental polyp arising from an exaggerated placental site.

There are very few reported cases of the clinical course of exaggerated placental site, and a case of a placental polyp arising from an exaggerated placental site has not been reported previously. Here, we report a case of a 43-year-old woman whose chief complaint was of massive genital bleeding. She had undergone an operation for induced abortion in the first trimester 41 days previously. A placental polyp measuring 45 mm with an abundant blood flow could be detected by transvaginal color Doppler ultrasonography and enhanced magnetic resonance imaging. We performed a transabdominal simple total hysterectomy. At the anterior wall of the uterus, a protruding lesion into the uterine cavity was observed and a placental polyp was attached to the protruding lesion. The histological specimen of the protruding lesion, which was considered to be the implantation site, showed intermediate trophoblastic cells infiltrated into the myometrium. An exaggerated placental site was diagnosed, which might lead to a placental polyp.

Effects of pulmonary surfactant system on rifampicin release from rifampicin-loaded PLGA microspheres.

Pulmonary surfactants little affected the release ratio of rifampicin from rifampicin-loaded poly(lactide-co-glycolide) PLGA microspheres. The release ratio of rifampicin was depending on pH of pulmonary surfactant solution, showing that rifampicin-loaded PLGA microspheres have an ideal property to deliver rifampicin into alveolar macrophages inside of which Mycobacterium tuberculosis bacilli reside and to kill them. That is, little amount of rifampicin is released in alveolar lining liquid before the microspheres are phagocytosed by alveolar macrophages, then rifampicin is released in phagosome or cytoplasm, but little amount of rifampicin is released in lysosome of alveolar macrophages after the microspheres are internalized. Pulmonary surfactants also little affected the changes in molecular weight of residual PLGA during its hydrolytic degradation process. From the electrophoretic mobility measurements of PLGA microspheres, it was shown that pulmonary surfactants changed the surface charge density of PLGA microspheres by adsorbing on their surfaces.