Inhibition of membrane Na(+)-K+ Atpase of the brain, liver and RBC in rats administered di(2-ethyl hexyl) phthalate (DEHP) a plasticizer used in polyvinyl chloride (PVC) blood storage bags.

Significant amounts of di(2-ethylhexyl) phthalate (DEHP) leach out into blood stored in DEHP plasticized polyvinyl chloride (PVC) bags resulting in the exposure of recipients of blood transfusion to this compound. The aim of this study was to find out whether DEHP at these low levels has any effect on the activity of membrane Na(+)-K+ ATPase, since a decrease in this enzyme activity has been reported to take place in a number of disorders like neurodegenerative and psychiatric disorders, coronary artery disease and stroke, syndrome-X, tumours etc. DEHP was administered (ip) at a low dose of 750 microg/100 g body weight to rats and the activity of membrane Na(+)-K+ ATPase in liver, brain and RBC was estimated.

Tryptophan and tyrosine catabolic pattern in neuropsychiatric disorders.

Catabolism of tryptophan and tyrosine in relation to the isoprenoid pathway was studied in neurological and psychiatric disorders. The concentration of trytophan, quinolinic acid, kynurenic acid, serotonin and 5-hydroxyindoleacetic acid was found to be higher in the plasma of patients with all these disorders; while that of tyrosine, dopamine, epinephrine and norepinephrine was lower. There was increase in free fatty acids and decrease in albumin (factors modulating tryptophan transport) in the plasma of these patients.

Changes in the composition of erythrocyte membrane during storage of blood in di-(2-ethyl hexyl) phthalate [DEHP] plasticized poly vinyl chloride (PVC) blood storage bags.

Very little information is available on the changes in the erythrocyte membrane composition during storage of blood at 4 degrees C, particularly with respect to the glycosaminoglycans and glycoproteins. In view of this, a detailed study was carried out on the changes in the membrane proteins, glycosaminoglycans (GAG), carbohydrate components of glycoproteins, cholesterol, phospholipids and vitamin E in blood stored in glass bottles and a di-(2-ethyl hexyl) phthalate (DEHP) plasticized PVC bag (Penpol blood bag). Blood was collected in CPDA solution in glass bottles and in Penpol blood bags and kept at 4 +/- 1 degrees C.

Decreased hemolysis and lipid peroxidation in blood during storage in the presence of nicotinic acid.

Background And Objectives: There is increase in lipid peroxidation with consequent increase in hemolysis when blood is stored in di-(2-ethyl hexyl)phthalate (DEHP) plasticized bags. Studies carried out by us and others have indicated the ability of red cells to synthesize NAD+ from added nicotinic acid. Apart from the role of NAD+ in glycolysis, NADPH is required for reduction of oxidized glutathione to its reduced form by glutathione reductase.

Synthesis of NAD+ in erythrocytes incubated with nicotinic acid and the effect of di-(2-ethyl hexyl) phthalate (DEHP).

Synthesis of NAD+ from nicotinic acid by erythrocytes incubated in SAGM phosphate solution and effect of di-[2-ethyl hexyl] phthalate, a plasticizer commonly used in PVC blood/component storage bags, on this synthesis was studied. Erythrocytes are able to synthesise NAD+ in SAGM (sodium chloride, adenine, glucose, mannitol) phosphate solution and this synthesis was more in the presence of added nicotinic acid (optimum concentration 1 mM). The level of NAD+ decreased when the incubation period was increased from 24 to 48 hr.

Decrease in the concentration of vitamin E in blood and tissues caused by di(2-ethylhexyl) phthalate, a commonly used plasticizer in blood storage bags and medical tubing.

Background And Objectives: Significant amounts of di(2-ethylhexyl) phthlate (DEHP) leach into blood stored in DEHP-plasticized PVC bags. The aim of this study was to find out whether DEHP at these low levels has any effect on the concentration of vitamin E, an antioxidant which affords protection against free radical damage.

Materials And Methods: DEHP was administered in low doses (150-750 microg/100 g body weight) to rats intraperitoneally and the concentration of vitamin E in the liver and testes was measured.

Toxic effect of systemic administration of low doses of the plasticizer di-(2-ethyl hexyl) phthalate [DEHP] in rats.

DEHP [di-(2 ethyl hexyl) phthalate], a widely used plasticizer in blood storage bags, leaches out in appreciable amounts into blood (about 10 mg/100 ml) resulting in exposure of recipients of blood transfusion to this compound. Various reports indicate the toxicity of DEHP, particularly in liver and reproductive organs but all these studies used large doses (up to 2 g or more/Kg body weight) and oral route of administration which are not relevant to the intravenous administration during blood transfusion or the low amounts present in blood. We have studied changes in the activity of some important enzymes-gamma-GT, ALT, CPK, LDH, alkaline phosphatase, acid phosphatase, beta-glucuronidase and few other parameters like vitamin E, glutathione, serum albumin etc in rats administered low doses of DEHP (corresponding to transfusion of 2, 4, 6 and 10 units of blood).

Effect of DEHP [di-(2-ethyl hexyl) phthalate] on lipid peroxidation in liver in rats and in primary cultures of rat hepatocytes.

The effect of DEHP [di-(2-ethly hexyl) phthalate] on lipid peroxidation in the liver in rats and in primary cultures of rat hepatocytes incubated with it was studied. The doses of DEHP used in this study corresponded to the low levels of this substance leaching into blood stored in DEHP plasticised PVC bags. Increased activity of superoxide dismutase (SOD) and catalase, increased concentration of malondialdehyde (MDA) and conjugated dienes and decrease in the concentration of glutathione and vitamin E have been observed in the liver of rats administered DEHP.