[Intraperitoneal versus intravenous infusion of cis-platinum in advanced ovarian cancer--examination of pharmacokinetics]

The pharmacokinetics of i.p.- and i.v.-infused cis-platinum (55 mg/m2) was studied in five patients with advanced ovarian cancer. The area under the concentration time (AUC) of non-protein-binding platinum in ascites had on anti-tumor activity 44 times larger with i.p. infusion than that with i.v. infusion. Comparing with the concentration curve of non-protein-binding platinum in plasma, there was little difference between i.p. and i.v. infusion, and the AUC of non-protein-binding platinum was almost equal between i.p. and i.v. infusion. In cases of low renal function, cisplatin was infused at 70 mg/m2 with sodium thiosulfate (STS). The AUC of ultrafiltrable platinum in plasma was 3 times larger in STS combination therapy. Therefore, STS was confirmed to be a powerful antidote against cis-platinum in plasma. Amounts of total platinum in 24-h urinary secretion were slightly less for i.p. than for i.v. infusion. Consequently, i.p. infusion of cis-platinum was shown to be highly effective on the local site and as effective as i.v. infusion on the whole body. Moreover, this route is effective for reducing ascites production and is expected to be effective against metastatic sites other than the abdominal cavity.

[Ultrastructural study of the intercellular junction and lanthanum penetration in the mouse blastocyst]

Cell junctions in mouse blastocyst were ultrastructurally investigated with or without lanthanum tracer. Tight junctions, gap junctions and desmosomes were observed in the trophectoderm. The tight junction was located near the zona pellucida in all trophoblast interspaces, whereas the gap junction and the desmosome, which were infrequently observed, were localized far from the zona pellucida. However, the desmosomes in the trophectoderm of the expanded blastocyst after culture increased in number and came to be located near the zona pellucida. The trophoblast layer excluded lanthanum whose invasion was interrupted by the tight junction. There were a few intermediate junctions in the interspace between the trophoblast and the inner cell mass cell as well as between the inner cell mass cells. These findings indicate that a substances whose molecular weight exceeds that of lanthanum (138.9) may not flow into the blastocyst through the intercellular space. Moreover, it is speculated that the intercellular connection is strengthened during the expansion of the blastocyst.

Effects of indomethacin, prostaglandin E2, prostaglandin F2 alpha and 6-keto-prostaglandin F1 alpha on hatching of mouse blastocysts

The present study has been performed to investigate how PGs would participate the hatching process. Effects of indomethacin, an antagonist to PGs biosynthesis, on the hatching of mouse blastocysts were examined in vitro. Furthermore, it was studied that prostaglandin E2 (PGE2), prostaglandin F2 alpha (PGF2 alpha) or 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) were added to the culture media with indomethacin. The hatching was inhibited by indomethacin yet the inhibition was reversible. In the groups with indomethacin and PGE2, no improvement was seen in the inhibition of hatching and the inhibition was irreversible. In the groups with indomethacin and PGF2 alpha, inhibition of hatching was improved in comparison with the group with indomethacin. In the groups with indomethacin and 6-keto-PGF1 alpha, no improvement was seen. The above results indicated that PGF2 alpha possibly had an accelerating effect on hatching and a high concentration of PGE2 would exert cytotoxic effect on blastocysts.

[The evaluation of serum estradiol, progesterone, testosterone concentrations and urinary estrogen excretion level for the monitoring indices of follicular maturation]

We have evaluated serum estradiol, progesterone, testosterone, and urinary estrogen excretion in 24 hour urine samples to monitor indices of follicular maturation. The serum steroid levels were determined with the direct radioimmunoassay kit. The urinary estrogen level was measured with the estrogen micrometering kit using hemagglutination inhibition reaction. Moreover, relationships between these steroid levels and the follicular size measured with ultrasound were analyzed. The serum estradiol concentration and the estrogen excretion in 24 hour urine samples mostly showed a continuous increase during the late follicular phase, and had a positive correlation to the maximum follicular diameter of the leading follicle (MxFD) and to the total of the maximum diameter of the follicles (TFD). The serum progesterone concentration showed a remarkable increase especially on the day of the LH surge onset in many cases, and had a significant (p less than 0.01) correlation to MxFD but not to TFD. The serum testosterone concentration, however, showed neither a specific tendency on its daily change nor a correlation with the follicular size. These results indicated that the serum estradiol and progesterone, and the urinary estrogen excretion can be utilized as indices of follicular maturation.

[The effect of indomethacin on the implantation and metabolism of blastocysts]

The experiments were performed in order to reveal the role of prostaglandins in the implantation process, using indomethacin, a inhibitor of prostaglandin synthesis. Indomethacin was administered to mice on various days of pregnancy, and then the number of implantation sites and the uterine weight per the number of implantation sites were determined on day 10 of pregnancy. Furthermore [3H]uridine incorporation of blastocysts incubated in the medium containing indomethacin with/without prostaglandin F2 alpha was evaluated in vitro. The results were as follows. Indomethacin reduced the number of implantation sites in the uterus and the uterine weight per the number of implantation sites (embryonal growth). Indomethacin inhibited the [3H]uridine incorporation of blastocysts, but prostaglandin F2 alpha counteracted the effect of indomethacin. These results suggested that prostaglandins play a role in inducing implantation and embryonal growth, and that blastocysts might synthesize prostaglandins.

The uptake of [3H]estradiol by mouse preimplantation embryos in vitro

Mouse blastocysts collected on day 4 were cultured for 20 hours in media containing various concentrations of [3H]estradiol with/without 10(-6) M unlabelled estradiol. There was a significant reduction in the radioactivity of embryos cultured at 4 degrees C compared with that of embryos cultured at 37 degrees C. The radioactivity of embryos kept in the washing solution after washing was slight lower but showed no significant difference when it was compared with that of embryos not kept in this way. There was no significant difference between the radioactivity of embryos cultured in 2 X 10(-8) M [3H]estradiol and that of embryos cultured in 2 X 10(-8)M [3H]estradiol plus 10(-6)M non-labelled estradiol. Furthermore the radioactivity of embryos incubated in 2.5 X 10(-8)M [3H]estradiol is more than twice that of embryos incubated in 10(-8)M [3H]estradiol. These results demonstrate that preimplantation mouse embryos are capable of uptake and retaining of estrogen and that the mechanism of uptake is neither selective nor receptor mediated.

[Pharmacodynamic effects of the sustained-release tablet of isosorbide dinitrate and its bioavailability in conscious dogs (author's transl)]

Oral administration of isosorbide dinitrate (ISDN), 1 approximately 2 mg/kg, resulted in a dose-dependent decrease in the pulse pressure by reducing the systolic pressure and slightly elevating the diastolic pressure in conscious dogs. Therefore, this system was employed to evaluate the effectiveness of the sustained-release ISDN tablet as compared with that of the standard tablet. Four standard tablets (20 mg of ISDN) given in a single dose significantly decreased the pulse pressure, which became lowest at 2 hr after administration and returned to the near original level at 6 hr. On the other hand, with four sustained-release tablets (80 mg of ISDN) 4 hr was required to produce a maximum decrease, and at 10 hr, the pulse pressure was still much lower than the original level. The plasma concentration of ISDN was measured by a gas chromatographic method. The time course of the plasma concentration of ISDN after administration of each preparation was correlated with that of the decrease in the pulse pressure. This suggests that the system employed is useful in evaluating the bioavailability of various preparations of organic nitrates (ISDN). In addition, these data demonstrate that the sustained-release formulation of ISDN possesses a prolonged pharmacological effect.

Artificial surfactant therapy in hyaline-membrane disease

Ten preterm infants severely ill with hyaline-membrane disease (HMD) were given artificial surfactant endotracheally. Oxygenation and alveolar-arterial oxygen gradients improved, the levels of inspired oxygen and peak respirator pressure could be reduced, and many of the radiological abnormalities resolved. Acidosis and systemic hypotension were also reversed. In nine infants a patent ductus arteriosus became evident after recovery from HMD, necessitating further assisted ventilation. Eight infants survived, including five of six with birthweight less than 1500 g; two died of unrelated causes. Postnatal tracheal instillation of artificial surfactant may prove a useful treatment for severe HMD.