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At least 19 recordsLinked to original sources
PubMed1976

Capacity of immunologically purified FSH to stimulate cyclic AMP accumulation and steroidogenesis in Graafian follicles and to induce ovum maturation and ovulation in the rat.

Reference preparations of ovine follicle-stimulating hormone (NIH-FSH-S8 and S9; 10-50 mug/ml) induced ovum maturation and stimulated cyclic AMP formation, as well as progesterone and 17beta-estradiol secretion, by rat Graafian follicles in vitro. These actions of NIH-FSH were retained after immunoabsorption of any contaminating luteinizing hormone (LH) present in the preparations, by treatment with an antiserum to the beta-subunit of purified ovine LH (anti-betaLH). In contrast, the corresponding biological actions of NIH-LH-S18 (0.5-10 mug/ml) were abolished by treatment with this anti-betaLH serum. A highly purified FSH preparation (64-96 CD, 0.25 mug/ml) also triggered oocytic meiosis and increased follicular progesterone secretion in vitro. Intraperitoneal (ip) administration of anti-betaLH-treated NIH-FSH-S9 (50 mug/rat at 1430 h) consistently induced ovulation in proestrous rats in which the endogenous gonadotropin surge had been blocked by ip injection of either Nembutal (1345 h) or antiserum to the LH-releasing hormone (1200 h). Injection (ip) of anti-betaLH serum on its own into proestrous rats at 1200 h prevented ovum maturation and follicular rupture. We conclude that currently available reference preparations of ovine FSH possess the capacity to stimulate follicular adenylate cyclase, steroidogenesis, and ovum maturation in vitro, as well as ovulation in vivo, in the rat, and that this capacity cannot be attributed to contamination with material immunochemically identical with LH. However, it is inferred that the physiological triggering of ovulation and related events in this species depends principally on LH.

Animals↗
PubMed1979

Hormonal considerations in early normal pregnancy and blighted ovum syndrome.

The hormonal profiles of six pregnancies which terminated in miscarriage with the blighted ovum syndrome have been studied and compared with those of a group of patients similarly studied who had clinically normal pregnancies terminating in live birth at term. The serum chorionic gonadotropin (HCG) values were below normal or at the lowest limit of normal in five of six patients. Three patients had progesterone values within 1 SD of the normal, with normal serum estradiol values. It was concluded that the hormonal profile of early pregnancy is characterized by rising serum HCG and estradiol levels and a declining serum progesterone level from the 5th to the 8th week. The theoretical explanation for the dichotomy seems to be that the fetal adrenal anlagen, even at this early embryonic stage, can produce steroid precursors which are aromatized to estradiol. The production of progesterone, however, does not seem to be possible. Abnormal serum estradiol levels strongly suggest the absence of fetal development and a blighted ovum. However, no single hormonal level will distinguish between blighted ovum and potentially salvagable threatened abortion.

Abortion, Spontaneous↗
PubMed1977

Time course of ovum transport in guinea pigs.

The time course of ovum transport was determined in cycling guinea pigs. The occurrence of ovulation was determined in assessing changes in vaginal cytology. The day of the postovulatory leukocyte influx was considered day 1 of the cycle. Ovum transport in guinea pigs is characterized by a relatively long sojourn in the ampulla, followed by rapid transport through the isthmus. This pattern is similar to that seen in women and subhuman primates and different from the pattern in rabbits.

Animals↗
PubMed1979

Ovum transport in women treated with methyl ergonovine.

The location of ova in the genital tract was studied between 24 and 120 hours after the luteinizing hormone (LH) surge in 32 women who had been treated with methyl ergonovine in doses known to stimulate tubal contractility. Thirteen eggs were found in the fallopian tubes, between 48 and 120 hours after th LH peak, and no eggs were recovered from the endoemtrial cavity. No significant difference in tubal ovum recovery or in tubal segmental distribution of ova was found in comparison with these parameters in an untreated control group. These results indicate that stimulation of tubal contractility with methyl ergonovine does not accelerate ovum transport through the fallopian tubes in the human.

Ergonovine↗
PubMed1975

Effects of hormonal treatments which alter ovum transport on beta-adrenoceptors of the rabbit oviduct.

Beta-Adrenoceptor activity of rabbit oviductal isthmus has been determined quantitatively in vitro in tissues isolated 24 and 72 hours after human chorionic gonadotropin injection and after two hormonal treatments known to accelerate (progesterone) and retard (estrogen) ovum transport. Under conditions in which ova are located at the ampullary-isthmic junction and distal isthmus, the isthmus demonstrates a low incidence of spontaneous activity in vitro, poor response to acetylcholine, low affinity of beta-adrenoceptors for isoproterenol, and low efficacy of isoproterenol to inhibit acetylcholine-induced contractions. Under conditions in which ova are passing into the uterus, the isthmus shows the converse of these parameters. These data support the hypotheses that the oviductal isthmus functions as an adrenergic sphincter and that the actions of progesterone and estrogen in altering ovum transport rates are at least partially mediated through changes in adrenoceptors.

Acetylcholine↗
PubMed1978

Endotoxin-induced acceleration of ovum transport in rabbits.

Salmonella enteritidis-Boivin endotoxin (1--20 microgram/kg) induced accelerated oviductal ovum transport in rabbits in a dose-related manner. Indomethacin prevented this effect. Levels of prostaglandin E and F in uterine vein blood increased following endotoxin injection.

Animals↗
PubMed1979

Relationship between concentration of prostaglandins E and F in the regulation of ovum transport in rabbits.

Prostaglandin E and F levels were measured by a radioimmunoassay technique in different parts of the rabbit fallopian tube treated with indomethacin and in untreated rabbit at 0, 24, 48 and 72 hours after Human Chorionic Gonadotrophin (HCG) administration. The results indicate a significant rise in the levels of PGE and fall in the levels of PGF throughout the isthmus at 48 hours and in the distal isthmus at 72 hours in the untreated rabbits. In the indomethacin treated rabbits, PGF levels were reduced relatively more than PGE levels in different parts of the rabbit fallopian tube at various time intervals after HCG administration. Prostaglandins E and F may have a role in regulating ovum transport.

Animals↗
PubMed1977

Effect of inhibitors of prostaglandin synthesis and metabolism on ovum transport in the rabbit.

Several drugs known to affect prostaglandin synthesis, release, or metabolism have been tested for their effects on ovum transport in the rabbit after systemic or local administration. Acceleration of transport was obtained with several drugs; among the most effective were benzydamine, a blocker of thromboxane production, and L11204, an inhibitor of prostaglandin metabolism.

Animals↗
PubMed1978

Polycationic macromolecules inhibit cilia-mediated ovum transport in the rabbit oviduct.

In both in vitro and in vivo experiments, polycationic macromolecules,such as poly(L-lysine), inhibited the transport of either surrogate or freshly ovulated cumulus masses across the oviduct epithelial surface without affecting the ciliary beat. Whereas transport across the fimbria in vivo was completely inhibited, transport down the ampulla was 3 to 7 times slower than normal. The effects of these polycations suggest that cilia-mediated ovum transport may involve the formation of transient adhesive bonds between the tip of the cilium and elements of the cumulus mass during each beat cycle of the cilium.

Animals↗
PubMed1979

New observations on the structure of the hen ovum at ovulation.

Scanning electron microscopy of the perivitelline layer (PL) of a hen body cavity ovum revealed dispersed groups of atrophied granulosa cells. Those overlying the animal pole were flattened and had numerous ramifying processes which penetrated the porous ground substance of the PL. Alternatively, the granulosa cells overlying the vegetal pole were rounded and formed fewer processes which penetrated a nonporous ground substance. The latter observation suggests that the PL is not structurally uniform in all ova.

Animals↗
PubMed1976

Transmission of auto-immune haemolytic anaemia and murine leukaemia virus in F1 (BALB/c X NZB) hybrid mice derived by ovum transplantation.

F1(BALB/c X NZB)hybrid progeny derived by ovum transplantation were used to study the transmission of auto-immune haemolytic anaemia and murine leukaemia virus (MuLV) by male New Zealand black (NZB) mice. Fertilized ova, collected from the normal BALB/c partners 3 1/2 days after mating, were transferred to other, surrogate, BALB/c mothers, which then carried, delivered, and reared the hybrid young. This technical manoeuvre effectively closed the congenital transplacental route theoretically available to any infectious MuLV originating from the NZB father. Nevertheless, such progeny developed exactly the same profile of auto-immune haemolytic disease and the same range of diverse malignancies as their normally-derived F1(BALB/c X NZB) counterparts, and they carried type C MuLV particles readily detectable by electronmicroscopy. We concluded, therefore, that both the auto-immunity and virus were transmitted before placentation, presumably by the NZB male at fertilization, and probably as genetic information.

Anemia, Hemolytic, Autoimmune↗
PubMed1979

Fine structural localization of alkaline phosphatase in rat ovum during cleavage.

On a submicroscopic level alkaline phosphatase activity was demonstrated by cytochemical methods in all stages of segmenting rat ova under survey, i.e. in the unfertilized and fertilized ovum, in the two-, four- and eight-cell stages and in the blastocyst. The reaction product was present in some cytoplasmic organelles as well as on cell membranes. A considerable number of cytoplasmic organelles with alkaline phosphatase activity was found in all stages from the one-cell up to the eight-cell stage. The reaction product was deposited in the tubules and vesicles of the smooth endoplasmic reticulum, in the nuclear envelope and in the Golgi complex as well. Some multivesicular bodies, autophagic vacuoles and majority of residual bodies out of the secondary lysosomes showed enzymatic activity. In the multicellular stages no significant differences were observed between the individual blastomeres in the incidence and distribution of the alkaline phosphatase activity. On the blastocyst-stage was found a low incidence of enzymatically active cytoplasmic organelles. Alkaline phosphatase activity was demonstrated in some minute vesicles below the cell membrane and in some secondary lysosomes. No essential differences were found between the cells of the embryoblast and the cells of the trophoblast in the incidence of enzymatically active structures. In the one-cell stage the activity of alkaline phosphatase was present on the cell membrane only sporadically, in the two- and four-cell stages enzymatic activity was found in this localization in a third of all specimen. In the eight-cell stage alkaline phosphatase activity was demonstrated on the cell membranes of all blastomeres. In the blastocyst the reaction product was deposited regularly on the membranes of the trophoblastic cells turned towards the zone pellucida, frequently on membranes of mutual tactile cells of the trophoblast and the embryoblast and only sporadically on cell membranes limiting the blastocyst cavity.

Alkaline Phosphatase↗
PubMed1979

Interaction of estrogen and histamine during ovum implantation in the rat.

The relationship between estrogen and histamine in the initiation of ovum implantation in the rat was studied. Histamine was found to augment the implantation response to suboptimal doses of estradiol in the ovariectomized pregnant rat maintained with Depo-Provera. The effect of histamine was found to involve both H1- and H2-receptors and to be inhibited by treatment with a combination of mepyramine and metiamide. Treatment with this combination of histamine antagonists during early pregnancy in the intact rat did not modify blastocyst attachment. It was concluded that the effect of histamine on the implantation response to exogenous estradiol was due to increased uterine blood flow and/or estrogen uptake but that such histamine-mediated effects were not essential for blastocyst attachment during normal pregnancy.

Animals↗