Gynecologic and Obstetric Investigation

doi: 10.1159/000302034pmid: N/A

Carr, M.C.

doi: 10.1159/000302021pmid: N/A

The ability of related or unrelated intrapartum maternal plasma to damage the syncytiotrophoblast lining of human placental chorionic villi was studied using a suspension culture system. It was found that the degree of syncytiolysis was a function of concentration of plasma, length of incubation, and incubation temperature. Less cytolytic activity was evidenced when the plasma was heated for 1 h at 56 °C or if the initial pH of the medium was decidedly alkaline. Although the precise mechanism for this cytolysis was unclear, this study established that maternal plasma can severely damage syncytial trophoblast in vitro. This may have relevance as one of the available pathways by which syncytiotrophoblast can be damaged in vivo.

Pauerstein, C.J.; Fremming, B.D.; Martin, J.E.

doi: 10.1159/000302022pmid: N/A

Previous investigations of the influence of exogenous progesterone on the rate of egg transport through the rabbit oviduct have yielded some conflicting data. This study was designed to measure the effects of exogenous progesterone on tubal ovum passage, and to examine possible interaction between alpha adrenergic receptors and progesterone. Groups of New Zealand does were given progesterone for 3 days prior to ovulation, or on the day of ovulation and the 2 following days. Some groups were treated with phenoxybenzamine in doses sufficient to induce alpha adrenergic blockade. Progesterone given prior to ovulation accelerated ovum transport through the oviduct. When given after ovulation, progesterone did not increase the rate of transport of eggs through the oviduct. Phenoxybenzamine treatment did not alter the changes in rate of egg transport induced by progesterone.

Huisjes, H.J.; Wobbes, T.

doi: 10.1159/000302023pmid: N/A

Previous studies have suggested the possibility of diagnosing post-maturity by the demonstration of C-reactive protein (CRP) in amniotic fluid by latex agglutination tests. In our study we found that 72 of 75 samples of amniotic fluid obtained from mothers at varying times of gestation gave a positive latex agglutination reaction. The latex agglutination test, therefore, appears to be of no value for the diagnosis of post-maturity.

Wobbes, T.; Huisjes, H.J.

doi: 10.1159/000302024pmid: N/A

Employing several methods, we investigated the identity of a substance in human amniotic fluid which gives a positive agglutination reaction with latex-albumin. It was shown that the substance was particulate and originated from the vernix caseosa.

Aleem, F.A.; Valdivia, E.; Colás, A.E.

doi: 10.1159/000302025pmid: N/A

Examination with the electron microscope showed that mitochondrial and microsomal fractions from py human placenta were not homogeneous, despite their careful preparation by several methods. Repeated washing of the mitochondrial fraction, which substantially reduced its glucose-6-phosphatase activity, caused only a small decrease in the aromatizing activity of this fraction. In incubations with 4-androstene-3,17-dione, testosterone and 3Β-hydroxy-5-androstene-17-one, the ratio of 17Β-estradiol to estrone produced was greater with the microsomal ( > 2.00) than with the mitochondrial fraction (0.59–1.82) at each substrate level.

Braaksma, J.T.; Janssens, J.; Eskes, T.K.A.B.; Arp, A.; Hein, P.R.

doi: 10.1159/000302026pmid: N/A

In order to resolve some of the conflicting opinions concerning the relative accuracy of open vs. closed systems used in recording uterine activity, the various types of catheter recording systems were tested under in vivo and in vitro conditions. The findings indicate that open tip catheters accurately reflect true manometric pressures. Balloon tip catheters not only fail to record accurately, but are also subject to additional errors as the recording continues, or if there is any alteration of the fluid volume within the balloon at any time during the recording.

Martin, J.E.; McGuire, W.L.; Pauerstein, C.J.

doi: 10.1159/000302027pmid: N/A

Macromolecular binding of estradiol in the ampullary and isthmic portions of the rabbit oviduct and the rabbit uterus was examined by in vivo uptake studies, sucrose gradient centrifugation, and binding assays. The studies revealed that the in vivo uptake was similar in the 3 mullerian areas examined. In addition, the estrogen receptor complex from all 3 areas had almost identical sedimentation characteristics in sucrose gradient centrifugation. Finally, the binding assays revealed that the number of estrogen-binding sites and the dissociation constants were similar in the 3 areas studied. These results indicate that the initial interaction of estrogen with the uterus and both portions of the oviduct is identical.

Chez, R.A.; Josimovich, J.B.; Schultz, S.G.

doi: 10.1159/000302028pmid: N/A

These experiments examined the unidirectional transfer of radioisotopically-labeled human placental lactogen (HPL) across term human amnion-chorion using in vitro techniques. Conditions of both equal and unequal concentrations of nonlabeled HPL were employed in the bathing solutions. All the data indicate that the bidirectional transfer of HPL can be accounted for by simple diffusion. There is no evidence of asymmetrical transfer, obligatory exchange diffusion, solvent drag, or a carrier mediated process. These results do not provide an explanation for the difference in the maternal plasma and amniotic fluid concentrations of HPL that exist in human gestation at term. Rather, a fetal metabolic role is postulated.

Sadovsky, E.; Pfeifer, Y.; Polishuk, W.Z.; Sulman, F.G.

doi: 10.1159/000302029pmid: N/A

Intra-amniotic injection of pregnant rat mothers with pargyline HCl (Eutonyl), a MAO blocker, produces fetal death through activation of endogenous serotonin. In the present paper 5 progesterone derivatives were tested for their capacity to prevent serotonin abortion. While progesterone, dydrogesterone, medroxy-progesterone acetate and allylestrenol were not effective in preventing serotonin abortion, treatment with the retroprogesterone trengestone (RO 4-8347) prevented abortion and premature delivery in the 2nd and 3rd trimesters, though it could not prevent serotonin abortion in rats in the 1st trimester. The fetus-saving effect of trengestone appears to be due to the fact that it increases formation of serotonin-metabolizing enzymes, including MAO in the endometrium, whereas estrogens decrease it.