G. Kaur

Lipid peroxidation in tin intoxicated partially hepatectomized rats.

In recent years the toxic effects of tin have been the subjects of numerous studies. Studies from this laboratory have demonstrated that tin alters mitochondrial function, reduces the content of sulfhydryl groups and subsequently inhibits the activity of sulfhydryl containing enzymes. It was suggested that a possible mechanism for the altered physiology of the cells may involve lipid-peroxidation process. It has been reported that glutathione a cofactor for the selenium dependent GSH-peroxidase which reduces the content of lipid peroxides has been implicated in the defence mechanism against lipid peroxidation. The present work was designed, therefore, to investigate the effects of tin-tartrate on normal and regenerating hepatic tissue and to determine the extent of any association with lipid peroxidation and hepatic glutathione content. Regenerating rat liver, a growing model system, was taken into account to assess the health risk due to heavy metals pollution in a growing population.

The effect of triethylene tetramine upon the selective removal of nickel (II), iron (II), manganese (II) and tin (II) in rats

Abstract The distribution of Nickel-63, Iron-59, Manganese-54 and Tin-113 in plasma was studied in rats which received single intravenous (i.v.) injection of aqueous solutions of their salts alone, and in rats which also received single intramuscular (im) injection of triethylene tetramine (TETA). TETA was extremely effective in reducing the plasma concentration of Nickel-63 followed by that of Iron-59, Manganese-54 and Tin-113.

The distribution of manganese-54 in fetal, young and adult rats

The distribution of 54Mn in various organs of pregnant rats and of their 19-day-old fetuses and in non-pregnant female rats of various ages has been studied 18 h after an i.v. injection of 54MnCl2. The results indicate that early neonates are more susceptible to manganese (Mn) than the growing rats. The localization of 54Mn in liver and brain of the embryo was highly significant.

Effect of nitrilotriacetic acid (NTA) on the distribution of manganese-54 in rats

The effect of single dose of NTA on the removal of radio-manganese in various organs and in plasma has been studied in rats which received single i.v. injection of54Mn(II). The lowered value of radio-manganese in NTA treated rats as compared to control animal indicates that NTA binds rapidly and forms stable and diffusible complex resulting in the fast excretion of the injected54Mn(II).

Distribution of radiotin (Sn113) in partially hepatectomised rats and its binding with subcellular components of liver cells

Abstract Distribution of radiotin (Sn 113 ) in target organs and in the hepatic subcellular fractions was studied in sham and partially hepatectomised rats 72 hrs after the administration of tin (II) tartrate (2 mg Sn ++ , 10 uCi/100 gm body weight) intraperitoneally. The results indicate that in both the groups Sn 113 was maximally accumulated in liver followed by kidney and spleen. Partially hepatectomised rat however accumulated less Sn 113 in liver while an increase was observed in kidney. Subcellular studies showed significantly high affinity of tin for microsomes. A compartmental shift of radiotin from cytosol to microsomal fraction was observed in hepatectomised rats when compared to sham operated rats.

Metabolic activity of lysosomes in tin-intoxicated regenerating rat liver.

The metabolic activity of lysosomes was monitored by assaying the lysosomal enzymes. DNase, RNase, acid phosphatase and cathepsin in rat liver regenerating after partial hepatectomy at various intervals after the operation. Results of the present study demonstrate that the activities of lysosomal enzymes are increased significantly during the process of rapid regeneration, especially at 24 h and 48 h. A small rise in enzymatic activities was noticed at 36 and 72 h of regeneration, leading towards normalisation at 168 h. Administration of tin(II) tartrate (25 mu mol Sn2+/100 gm body wt.) significantly increased the DNAse and RNAse activity at 24 h of the regeneration, while a decrease was noticed in acid phosphatase activity. An increase was also found in the catheptic activity of tin-treated hepatectomized rats. It can thus be concluded that an increased metabolic activity of lysosomes is reflected by the increased activity of its hydrolytic enzymes during the regeneration, and tin at low concentrations is helpful to this process. Further work is in progress to gain insight into the other metabolic activity of the lysosomes during the process of regeneration.