Reproduction Parameters in Low Dose Chronic Exposure with Heavy Metals in Rats

Introduction In spite of intense attempts of legislative regulations in the last years the issue of envi-ronmental pollution and the restriction of existing resources of fresh water is far from solved. Clean air, drinking water and food are basic requirements for healthy life and therefore health professionals and biomedical researchers are in charge to draw the public attention to the pos-sible health risks and consequences of industrial and agricultural pollution of the air soil and water resources Many aspects of acute intoxication with heavy metals including their genotoxic, terato-genic and metabolic effects are relatively well known and are the subject of several in depth papers and reviews The main purpose of the present study was to evaluate changes in basic physiological and reproductive parameters due to lifelong exposition to low doses of heavy metals (lead, cadmium, mercury) in Wistar rats. This is an important prerequisite to find the most suitable and precise indicators for estimation of the risks of the chronic low-dose exposure with vari-ous harmful substances on healthy human population. Experimental Procedures Animals Experiments were carried on 80 Wistar albino rats of both sexes (40 females and 40 males, age at the beginning of study 4 weeks, average weight 120±19 g) and their 28-day old newborns. The animals were kept in male -female Polish J. of Environ. Stud. Vol. 17, No. 6 (2008), 911-915 Abstract The aim of this study was to evaluate the effects of low dose chronic lead, mercury and cadmium exposure on reproductive potency of Wistar rats and on their progeny. The number of litters and the number of newborns in rats exposed to Pb and Hg were significantly higher compared to controls whereas between Cd exposure group and controls was almost no differ-ence. In contrary, the survival rate of the weanlings decreased in the order Cd>Pb>Hg and in all epxosed group was higher than in controls. The results suggest, that increase in reproduc-tion rate early after intoxication onset may disclose certain reactive adaptation mechanisms. The number of weanlings appears to be a sensitive marker in reprotoxicity tests

Preventive Effects of Flavonoids on Alloxan-Induced Diabetes Mellitus in Rats

The aim of the present study was the evaluation of possible protective effects of quercetin and chrysin in experimental alloxan-induced diabetes in rats. Alloxan was injected at a single dose of 60 mg/kg (into the tail vein) for diabetes induction. Quercetin (50 and 100 mg/kg; orally) and chrysin (50 and 100 mg/kg; orally) were administered daily for 3 days prior and 7 days after alloxan injection. Alloxan induced a significant increase of glycaemia (p p p p < 0.01). On the other hand, glycosuria was increased in all groups of animals receiving alloxan. We suggest that the protective effect of the used flavonoids in experimental diabetes mellitus may be related to their antioxidative/chelatory properties. Increased glycosuria indicated that inhibition of renal glucose reabsorption may also play a role in the hypoglycaemic effect of both flavonoids

Effect of Low-Dose Exposure to Toxic Heavy Metals on The Reproductive Health of Rats A Multigenerational Study

The aim of this investigation was to evaluate the effects of the exposure to low doses of lead, mercury and cadmium dissolved in drinking water (200× above maximal permissible dosage) on the reproductive potency of 200 Wistar rats (100 males and 100 females of F1 generation) and their progeny. Ten groups of rats were formed according to their exposure to heavy metals, including one control group without exposure. The females gave births between weeks 13 and 78 of the experiments. Reproduction parameters, such as number of litters, total number of newborns, number of newborns per litter, and number of weanlings were assessed weekly. The results demonstrated that the number of litters and newborns were higher after exposure to mercury and lower after exposure to lead. The number of weanlings and their share from newborns were the highest after exposure to cadmium and the lowest after exposure to mercury. A sex-specific effect of metals was related to the reproductive success