Biomedical subjects

M G Subramanian

Publications and source records attributed to M G Subramanian.

76 records · Page 5Linked to original sources

PubMedDate not supplied

Comparative effects of prenatal cocaine, alcohol, and undernutrition on maternal/fetal toxicity and fetal body composition in the Sprague-Dawley rat with observations on strain-dependent differences.

Pregnant rats received either 20, 30, 40, or 50 mg/kg cocaine HCl (SC) twice daily from gestation days 7 through 19. Pair-fed and untreated control groups and a group receiving 3.0 g/kg alcohol (PO) twice daily served as comparison groups. Females were sacrificed on gestation day 20 and the fetuses examined. Maternal weight gain and food consumption showed dose-dependent decreases. Maternal water consumption, by contrast, was significantly increased in the cocaine-treated animals and may reflect a diuretic effect. The maternal mortality rates in Sprague-Dawley rats were less than in two strains of Long-Evans rats, suggesting important strain-dependent differences in susceptibility to cocaine toxicity. Cocaine caused a significant dose-dependent decrease in fetal weights. Physical anomalies in the cocaine-exposed and alcohol-exposed fetuses included occasional hemorrhaging, edema, anophthalmia, and limb reduction. Despite increased maternal water consumption by cocaine-treated dams, there were no increases in fetal body water content. There were, however, significant decreases in fetal body fat content in the pair-fed, alcohol-treated, and two highest cocaine-treated groups.

Analysis of Variance↗

PubMedDate not supplied

Sulpiride-induced increases in serum prolactin levels in female rats exposed prenatally to alcohol.

We examined the impact of prenatal alcohol exposure on serum prolactin levels and on the ability of the D2 dopamine antagonist sulpiride to stimulate prolactin release in Long-Evans rats. Pregnant rats were intubated with alcohol (0, 3, or 5 g/kg/day) from gestational day 8 (GD8) to GD20. Adult female offspring were screened for estrous cycle stage. At diestrus, the rats were challenged with a single dose of sulpiride (0, 10, or 40 micrograms/kg) and trunk blood was collected 20 min later. After prenatal exposure to either dose of alcohol, mean basal serum levels of prolactin were about 65% less than the 0 g/kg group, and the 35-40% mean differences from an untreated control group were not significant. Sulpiride produced dramatic dose-dependent increases in serum prolactin levels in all prenatal treatment groups. Across all doses of sulpiride, the group given the higher dose of prenatal alcohol (5 g/kg/day) had significantly lower serum prolactin levels than all other groups. There was no significant interaction between prenatal treatment and sulpiride dose. Neither prenatal alcohol exposure nor sulpiride injections had significant effects on serum corticosterone levels in this study. Although the current results are unclear regarding a baseline decrease in prolactin levels after prenatal alcohol exposure, the overall results suggest that prenatal alcohol exposure decreases prolactin levels but there is no evidence that it does so by altering dopaminergic tone in hypothalamus of female rats.

Animals↗

PubMedDate not supplied

Prolactin size heterogeneity in human follicular fluid: a preliminary study.

Follicular fluid from mature preovulatory follicles was examined for the presence of prolactin (PRL) heterogeneity. Two pools of follicular fluid aspirates were used: one from follicles in which the ova were successfully fertilized in vitro and the other from follicles in which the ova were not successfully fertilized. Follicular fluid aspirates were concentrated by ultrafiltration and subjected to Sephadex G-100 gel chromatography. Fractions were assayed for immunoactive PRL by radioimmunoassay (RIA-PRL) and for bioactive PRL by the Nb2 lymphoma cell bioassay (BA-PRL). The major portion of RIA-PRL activity appeared as a low-molecular-weight component and accounted for 88% of the total PRL activity in the fertilized group and 87% in the unfertilized group. A high-molecular-weight component was also evident (12% and 13% for the two groups, respectively). The high-molecular-weight component in both groups was not active as PRL in the bioassay. These results demonstrate that while two immunoactive, heterogeneous forms of PRL exist in human follicular fluid when measured by RIA, it is only the low-molecular-weight form of PRL that is biologically active as established by Nb2 lymphoma cell bioassay.

Biological Assay↗

PubMedDate not supplied

Evaluation of the preovulatory rise of follicle stimulating hormone and progesterone in normally ovulating women of reproductive age.

Sixteen normally ovulating women of reproductive age were evaluated to determine the extent of the preovulatory FSH and progesterone rise in association with the LH surge. Highly significant differences were demonstrated between the baseline and peak preovulatory levels of both FSH and progesterone (P less than .0005). These significant peak ovulatory differences of FSH and progesterone were associated with a 2.5-fold rise (mean difference of 9.06 mIU/mL) of FSH and a 3.0-fold rise (mean difference of 1.94 ng/mL) of progesterone. These small, yet very significant, preovulatory increments of FSH and progesterone are important in the ovulatory process and the formation of an adequate corpus luteum.

Adolescent↗