ABSTRACT
The influence of short-term exposure to lead on the energetic status of erythrocytes in rats is reported in this study. The male Wistar rats selected for this study drank water containing 1% lead(II) acetate and/or intraperitoneal injections of 1 or 2 mg/kg body wt every 4 d starting on the eighth of the experiment, over a period of 1 mo. The whole-blood lead concentration measured after 4 wk was 1.51-35.31 microg/dL. The concentrations of adenosine, adenosine triphosphates, diphosphates, and monophosphates (ATP, ADP, and AMP), guanine triphosphates, diphosphates and monophosphates (GTP, GDP, and GMP), guanosine (Guo), inosine (Ino), inosine monophosphate (IMP), hypoxantine (Hyp), and nicotinamide dinucleotide and its phosphate (NAD(+) and NADP(+)) were determined by high-performance liquid chromatography (HPLC). The mean concentrations of ATP, GTP, NAD(+), and NADP(+) and those of adenylate (AEC) and guanylate (GEC) were significantly reduced in erythrocytes from the animals exposed to lead when compared to untreated controls. These results suggest that a lead ion disrupts the erythrocyte energy pathways. The decreases of NAD(+) and ATP could be used as an indicator of the extent of exposure to low levels of lead.
Subject(s)
Erythrocytes/drug effects , Organometallic Compounds/pharmacology , Purine Nucleotides/blood , Purines/metabolism , Adenine Nucleotides/blood , Administration, Oral , Animals , Energy Metabolism/drug effects , Guanine Nucleotides/blood , Hypoxanthine/blood , Injections, Intraperitoneal , Inosine Nucleotides/blood , Male , NAD/blood , NADP/blood , Organometallic Compounds/administration & dosage , Organometallic Compounds/blood , Rats , Rats, WistarABSTRACT
The aim of this work was to evaluate the influence of chronic exposure to lead ions on the parameters of energetic status of human erythrocytes in vitro. Umbilical cord erythrocytes were incubated with lead acetate at final lead ion concentrations ranging from 10 to 200 microg/dl. ATP, ADP, AMP, adenosine, GTP, GDP, GMP, guanosine, IMP, inosine, hypoxanthine, NAD and NADP concentrations in erythrocytes were determined using HPLC. Scanning electron micrographs of erythrocytes were taken. The mean concentrations of ATP, GTP, NAD and NADP, and mean values of adenylate energy charge (AEC) and GEC in cells incubated at the presence of lead ions were significantly lower after 20 h of incubation. Concentrations of purine degradation products (Ado, Guo, Ino) and Hyp were significantly higher. It is suggested that lead ions affect the energy metabolism of erythrocytes. Morphological changes in erythrocytes correspond to the increase of lead ions in the incubation mixture and to the decrease of ATP concentration in erythrocytes. A decrease in NAD and ATP concentration in erythrocytes could be a sensitive indicator of energy process disturbance, useful in monitoring in case of chronic lead exposure.
