Dr. B. Gholamhosseini, Dr. A. Khaki, Dr. Aa. Khaki, H. Kachabi, F. Radsaeed, Volume 14, Issue 4 (1-2009)
Abstract
Background and Aim: Lead is one of the world wide using metals that has been used since ancient time. It is also a toxin, known to have adverse effects on the body even at low level of exposure and it induces a bread range of physiological, biochemical and behavioral dysfunctions. Studies have shown that this metal has harmful effects on several tissues such as nervous system, blood tissues, cardiovascular system, reproductive and urinary system.
Materials and Methods: In this experimental study white male rabbits of New Zealand race were used and divided into two groups. Experimental group (N=10) 6.5 mg/kg of lead acetate were injected intra peritoneal every other day to each animal for 7 weeks as chronic dose and control group (N=10) were injected only with demonized water. After taking biopsy from left ventricular heart tissues of each group, tissue preparation was performed for LM and EM studies as standard method. Morphologic study was carried out on electron micrographs. Data have been compared with statistical methods.
Results: Electron microscopic study revealed the nuclei of left ventricular muscles were heterochromatin appearance and abnormality and vacuolization in mitochondria in experimental group when compared with control group. Morphological findings in experimental group showed that histological tissue changes have been more significant to control group (p<0.05).
Conclusion: These results suggest that lead acetate had severing effects on heart tissue during chronic dose.
Mr. Javad Hami, Mr. Alireza Ebrahimzadeh Bideskan, Mr. Gholamreza Dashti, Mr. Aliakbar Rajabzadeh, Volume 16, Issue 1 (4-2010)
Abstract
Background and Aim: Previous studies have demonstrated that lead exposure has destructive effects on some body systems. Lead, as a heavy metal, may produce variety of toxicity effects on endothelial cells lining luminal surface of the vascular system. Any changes or damages to endothelial cells may lead to cardiovascular diseases especially formation of atherosclerotic plaques. The aim of this study was to determine the effect of lead exposure on endothelium in the aorta and left coronary vessels in male rabbits.
Materials and Methods: Twenty white male rabbits (weighing 1.8-2 kg, and 4 months old) were obtained and divided randomly into a control group of nine and an experimental group of eleven. Both experimental and control groups were fed with a normal diet. The experimental group was given leaded water (547 ppm) and the control group was given unleaded water for 40 days. After treatment, all the rabbits were sacrificed and their thoracic aorta and left coronary artery were removed and processed according to routine histological methods. Formalin fixed, paraffin embedded and 5μm thickness sections were deparaffinized, rehydrated and stained with heamatoxilin-eosin and were then photographed.
Results: The results showed that lead can create pathological changes in endothelium of aorta and left coronary artery including disruption of endothelial cells, blood cells adhesion and aggregation on inner surface of mentioned vessels.
Conclusion: According to our findings, lead can cause morphological changes in endothelium. Thus, lead exposure may result in endothelial dysfunction, atherogenesis and cardiovascular pathogenesis.
