D Krakow — Page 2 | PubMed Health

PubMed1994

Endothelium-derived relaxing factor inhibition and the pressor response to norepinephrine in the pregnant rat.

OBJECTIVE: To determine whether endothelium-derived relaxing factor (EDRF) plays a role in the blunted pressor response to norepinephrine that is characteristic of normal pregnancy. METHODS: Eleven pregnant (mean +/- standard error of the mean 18 +/- 1 days of gestation) and 11 virgin conscious, unrestrained Sprague-Dawley rats with long-term indwelling vascular catheters were studied. Mean arterial pressure (MAP) and heart rate were measured in response to continuous infusions of either vehicle (5% dextrose) or increasing concentrations of norepinephrine (25, 100, and 200 ng/kg/minute) before and after administration of NG-monomethyl-L-arginine (LNMMA), a specific inhibitor of EDRF synthesis. RESULTS: Baseline MAP was lower in pregnant than in virgin rats (96 +/- 3 versus 105 +/- 3 mmHg; P < .05). Before LNMMA administration, the pregnant rats exhibited a significantly blunted pressor response to increasing concentrations of norepinephrine compared to that of virgin rats (P < .005). Given alone, LNMMA produced a greater increase in baseline MAP in virgin rats than in pregnant rats (rise in MAP of 44 +/- 2 versus 31 +/- 2 mmHg; P < .001). However, LNMMA abolished the blunted pressor response to norepinephrine in the pregnant animals and did not significantly affect the pressor response to norepinephrine in virgin rats. Heart rate responses to increasing concentrations of norepinephrine in the presence and absence of LNMMA were not significantly different in the two groups of animals. CONCLUSION: Stimulated EDRF production may contribute to the blunted pressor response to norepinephrine characteristic of pregnancy in the rat.

Analysis of Variance↗

PubMed1983

Coffee and pancreatic cancer: an analysis of international mortality data.

This study assessed the relationship of per capita coffee imports and consumption, total dietary fat, saturated fat, cholesterol, tobacco, cigarettes, and national income for 1957-1965 to age-adjusted pancreatic cancer death rates of men and women from 22 countries in 1971-1974. With simple correlation analysis, coffee, total dietary fat, saturated fat, and national income were each significantly correlated with both male and female pancreatic cancer mortality. Bivariate partial correlation coefficients of coffee with pancreatic cancer mortality were significant (one-tailed) in 11 of 12 analyses and borderline significant in two-way analyses of variance (ANOVA) (two-tailed) controlling for each of the other variables. Saturated fat and pancreatic cancer were also significantly related in univariate analyses, and in 11 of 12 bivariate partial correlation analyses; in ANOVA, significance was borderline in 10 of 12 analyses. Total fat and pancreatic mortality were also significantly associated in most of the univariate and bivariate correlation analyses, but not in the two-way analyses of variance. The findings of this study are consistent with the hypothesis that coffee and dietary lipid are involved in the etiology of pancreatic cancer.

Adolescent↗