Effect of acute exposure to cadmium on the expression of calcitonin gene-related peptide (CGRP), calcitonin (CT), somatostatin (SST) and synaptophysin (SYN) in the C cells of the rat thyroid - a preliminary study

The aim of the present study was to determine to what degree acute exposure to cadmium affects the expression of CGRP, CT, SST and SYN in the C cells of the rat thyroid. Animals from 7 experimental groups received CdCl2 iv. in doses of 3.5, 3, 2.5, 2, 1.5, 1 and 0.5 mg/kg b.w. respectively, while the control animals were given 0.9% NaCl iv. 24 hours after the iv. administration of CdCl2, a correlation was found between a single dose of cadmium and the intensity of the immunocytochemical reactions for CGRP, CT, SST and SYN in C cells of the rat thyroid when compared to the control. The weakest immunocytochemical reactions were noted in C cells of the thyroid of rats from Groups I and II, their intensity gradually increasing in Groups III, IV and V in comparison to the control. The reaction intensity in animals of Groups VI and VII resembled those of the control

Wolbachia Infection Decreased the Resistance of Drosophila to Lead

Background: The heavy metal lead has been shown to be associated with a genotoxic risk. Drosophila melanogaster is a model organism commonly utilized in genetic toxicology testing. The endosymbionts — Wolbachia are now very common in both wild populations and laboratory stocks of Drosophila. Wolbachia may induce resistance to pathogenic viruses, filarial nematodes and Plasmodium in fruit fly and mosquito hosts. However the effect of Wolbachia infection on the resistance of their hosts to heavy metal is unknown. Methodology/Principal Findings: Manipulating the lead content in the diet of Drosophila melanogaster, we found that lead consumption had no different effects on developmental time between Wolbachia-infected (Dmel wMel) and –uninfected (Dmel T) flies. While in Pb-contaminated medium, significantly reduced amount of pupae and adults of Dmel wMel were emerged, and Dmel wMel adults had significantly shorter longevity than that of Dmel T flies. Lead infusion in diet resulted in significantly decreased superoxide dismutase (SOD) activity in Dmel T flies (P,0.05), but not in Dmel wMel flies. Correspondingly, lead cultures induced a 10.8 fold increase in malonaldehyde (MDA) contents in Dmel T larvae (P,0.05). While in Dmel wMel larvae, it resulted in only a 1.3 fold increase. By quantitative RT-PCR, we showed that lead infused medium caused significantly increased expression level of relish and CecA2 genes in Dmel T flies (P,0.01). Lead cultures did not change dramatically the expression of these genes in Dmel wMel flies