Nonpregnant Female Mice Research Articles

Maternal-fetal distribution of methaqualone in control and SKF 525-A-pretreated pregnant mice

Male mice and pregnant and nonpregnant female mice were pretreated with saline or SKF 525-A (50 mg/kg, ip) and gavaged 1 hr later with [ 14C]methaqualone (MTQ) (25 mg/kg). Unchanged [ 14C]MTQ was determined in some or all of the following tissues: brain, spinal cord, eye, liver, lung, heart, spleen, kidney, muscle, fat, uterus, plasma, amniotic fluid, placenta, whole fetus, fetal brain, and liver. In saline controls, the MTQ concentrations in most adult tissues, whole fetus, and fetal brain and liver reached peak values at 1.5 hr. The tissue to plasma concentration ratios for fat and uterus were 4.5 and 1.1, respectively; those for other tissues varied from a low of 0.3 for amniotic fluid to a high of 0.8 for liver. At 1.5 hr, the fetal brain and liver contained concentrations of MTQ lower than the corresponding maternal tissues. Except for fat, the amounts in various tissues declined to trace amounts at 24 hr. Brain, plasma, lung, and liver concentrations in males and nonpregnant females were not different from each other but were significantly lower than those in pregnant mice. SKF 525-A pretreatment shifted the peak concentrations of MTQ to 3 hr in most tissues and caused marked tissue elevations.

Oxonic acid and fetal development: I. Embryotoxicity in mice

Feeding the uricase inhibitor potassium oxonate (K Ox) as 3% of the diet to pregnant mice during days 8–10 postconception caused a 95–98% incidence of embryonic mortality with resorption. The same treatment during days 10–13 of gestation caused no changes in litter size and fetal weight; however, if in addition to feeding K Ox, three concurrent i.v. injections of 2.5. mg/day of Na urate (Na UR) were given then 47% of the mouse fetuses were killed and resorbed. Intravenous Na urate alone during the same stages of early the middle pregnancy had no effect on fetal survical or development. A 3.6% incidence of cleft palate was caused in mice treated with the combination of K. Ox and Na UR during middle prenancy. In groups of mature nonpregnant female mice exposed to the same treatment regimens, serum uric acid, potassium and sodium were elevated in a treatment-related manner. Serum urea levels were unchanged. K Ox is lethal to mouse fetuses during early embryonic development. Hyperuricemia, hyperkalemia or hypernatremia are maternal alterations which may be responsible for, or contribute to this effect.

Placentophagia in nonpregnant rats: Influence of estrous cycle stage and birthplace

Prior parturitional experience and genotype have previously been found to affect the proportion of nonpregnant female rats and mice that will eat foster placenta. The present series of experiments was designed to investigate the influence of estrous cycle stage on placentophagia in rats. Foster placenta was presented to nonpregnant Long-Evans females, purchased from a commercial breeder, for 15 min on 5 consecutive days. We found that virgin placentophages were most likely to have eaten placenta on the first presentation, unless the first presentation occurred during proestrus. In fact, virgins would not eat placenta for the first time during proestrus, regardless of test-day. However, once they had eaten placenta, either in a nonproestrus stage, or, in the case of primiparae, during parturition, they would eat placenta during proestrus. Long-Evans rats born in our laboratory differed from the purchased rats, manifesting an incidence of placentophagia that was too low to be analyzed by stage of the estrous cycle: when tested as primiparae, however, there were no differences between the two groups.

Types B and C RNA virus in breast tissue and milk of wild mice.

Type B virus particles were found by electron microscopy in prelactating breast tissue and milk samples from many recently trapped pregnant wild mice from 3 trapping areas in southern California. Type C virus particles and the corresponding complement-fixing group-specific (gs) antigen were found in low incidence in prelactating breast and spleen tissues of mice from 2 of these areas. However, wild mice from the third trapping area showed a high prevalence of type C particles and gs antigen in these tissues and type C particles in milk. An increased incidence of spontaneous breast tumors, as well as lymphomas, was observed in nonpregnant female wild mice from this third trapping area.

DISTRIBUTION OF 109CdC12 IN PREGNANT MICE FED WITH THE DIET DEFICIENT IN VITAMIN A AND VITAMIN D

Retained amount and concentrations of cadmium in the kidney, liver, bones, digestive tract and others were compared between non-pregnant and pregnant female mice after the subcutaneous injection of carrier-free 109CdC12 solution. Mice were maintained with the synthetic diet without any particular addition of vitamins A and D. The cadmium concentration in the kidney of pregnant became double what it is in non-pregnant mouse on the average, but that in the bone was less in pregnant than in non-pregnant mouse.

Histopathology of Listeria monocytogenes after oral feeding to mice.

Ingestion by mice of Listeria monocytogenes in drinking water induced micro-abscesses of the liver and ulcerative enteritis. In pregnant mice, these lesions were larger and more extensive than in nonpregnant female and male mice. Pregnancy is interrupted by a purulent panmetritis and necrotizing placentitis. The early microabscess is unique in that it consists of monocytic cells with bizarre-shaped nuclei. The experimentally induced pathological changes in livers and intestines of mice used in this study are similar to those observed in listeric neonatal septicemia of human infants.

Histopathology of Listeria monocytogenes After Oral Feeding to Mice

Ingestion by mice of Listeria monocytogenes in drinking water induced micro-abscesses of the liver and ulcerative enteritis. In pregnant mice, these lesions were larger and more extensive than in nonpregnant female and male mice. Pregnancy is interrupted by a purulent panmetritis and necrotizing placentitis. The early microabscess is unique in that it consists of monocytic cells with bizarre-shaped nuclei. The experimentally induced pathological changes in livers and intestines of mice used in this study are similar to those observed in listeric neonatal septicemia of human infants.

Distribution of tritium-labelled tofenacine hydrochloride in the pregnant mouse

The distribution of tritium-labelled tofenacine hydrochloride after oral administration to pregnant mice was studied by means of a macroautoradiographic procedure. The distribution of radioactivity showed many points of resemblance with that in nonpregnant female mice, such as retention of the administered radioactivity in the stomach resulting from its atropine-like activity and a lower concentration of absorbed radioactivity in blood than in practically all the other organs. High levels were especially reached in the lungs, Harder's glands, thymus, lymph nodes, certain zones in the kidneys and adrenals, and to a lesser extent in the liver, salivary glands and bone marrow. A distinct penetration of radioactivity into the foetus was observed at the three periods gestation studied, namely 15, 17, and 19 days, although no correlation between these periods and the measure of penetration could be established. The placenta and especially the foetal membranes also showed a marked concenration of radioactivity. In mice pregnant for 19 days a foetal distribution pattern of radioactivity similar to that of the mother, was particularly striking. In the foetus of mice pregnant for 15 and 17 days, the differences in radioactivity between the various foetal organs were less pronounced. Various aspects of these findings are discussed.

Chapter II: Distribution of Labelled Vitamin B12 in Pregnant and Non-Pregnant Female Mice

Chapter II: Distribution of Labelled Vitamin B₁₂ in Pregnant and Non-Pregnant Female Mice

Chapter II: Distribution of Labelled Vitamin B12 in Pregnant and Non-Pregnant Female Mice

Chapter II: Distribution of Labelled Vitamin B12 in Pregnant and Non-Pregnant Female Mice

Chapter II: Distribution of Labelled Vitamin B12in Pregnant and Non-Pregnant Female Mice

Chapter II: Distribution of Labelled Vitamin B12in Pregnant and Non-Pregnant Female Mice

THE 5-HYDROXYTRYPTAMINE CONTENT OF THE PLACENTA AND FOETUS DURING PREGNANCY IN MICE.

5-Hydroxytryptamine (5HT) levels were measured in blood and tissues from pregnant mice. Blood levels remained constant during pregnancy and were the same as those in nonpregnant female mice. Placental levels of 5HT increased throughout pregnancy as did the foetal levels. The maternal blood volume of the placenta also increased with advancing gestation. 5HT levels were measured after treatment of the mother with 5HT, and the critical placental level of 5HT observed at about the time of death of the foetus was determined. The levels of 5HT in the placenta and foetus after treatment of the mother with several monoamine oxidase inhibitors were measured, and found to show no significant increase above the normal levels in these tissues. Treatment with cyproheptadine, a 5HT antagonist, did not delay parturition.

ELECTROPHORESIS OF SERUM PROTEINS AND SELECTED ENZYMES IN MALES, NON-PREGNANT, PREGNANT, AND LACTATING FEMALE MICE.

SummarySerum proteins and selected enzymes in non-pregnant, pregnant, lactating females and in male mice were studied by starch gel electrophoresis. Esterase and cholinesterase activity were present in all protein regions; alkaline and acid phosphatase, aminopeptidase, and cytochrome oxidase activity was associated with the protein beta region. Total protein was approximately the same in all categories of sera studied, but zymograms and protein stained gels showed that the relative concentrations of certain serum components were different in different sex, pregnancy or lactation categories. The relationship between these variations and possible transfer of maternal serum molecules to the oocyte or embryo is discussed.

Distribution of Plutonium in Mice: An Autoradiographic Study

The distribution of Pu²³⁹ was investigated by whole-body autoradiography in male mice, and pregnant and nonpregnant female mice, at 5 min up to 128 days after administration. The Pu was accumulated predominantly in the hard tissues but an uptake and retention were also observed in certain soft tissues such as the liver, ovarian follicles, fetal membranes, and mammary glands. (P.C.H.)