Study of the effects of BaCl(2) on the level of glutathione in plasma and cytosolic fraction in whole blood.

Barium has important role in the field of medical sciences, but it has been found in various studies that barium can cause numerous toxic effects. Studies have proven the strong affinity of the metalloelements for the sulfhydryl group (SH), present in reduced glutathione (GSH) and other biological molecules. In this context, the study about the possible interaction of BaCl(2) with glutathione in whole blood components was of interest, as an indication about the extent of barium toxicity and the role of glutathione in the conjugation and detoxification of the metalloelement barium. The concentration dependent and time dependent effect of BaCl(2) on the level of GSH in plasma and cytosolic fraction in whole blood was investigated, following Ellman's method. It was found that BaCl(2) causes a decrease in the GSH level, which is more pronounced with increasing concentration of BaCl(2) and with time incubation as well. The observed effect GSH concentration may be presumably due to production of oxidized glutathione (GSSG) or then due to barium-glutathione (GS-Ba-SG) conjugate formation.

Transgenerational marking of marine fish larvae: stable-isotope retention, physiological effects and health issues.

This study examined the toxicological and physiological responses of a commercially important coral-reef grouper, Plectropomus leopardus (Serranidae), to injection of enriched stable-isotope barium chloride (BaCl(2)) solution. Thirty adult P. leopardus were subject to one of two (138)BaCl(2) injection treatment groups (corresponding to dosage rates of 2 and 4 mg (138)Ba kg(-1) body mass), and a control group in which fish were injected with 0.9% sodium chloride (NaCl) solution. Fish from each group were sampled at post-injection intervals of 48 h and 1, 3, 5 and 8 weeks, at which time blood and tissue samples were removed from each fish. Residual concentrations of Ba and (138)Ba:(137)Ba ratios were measured in muscle, gonad, liver and bone tissues of each experimental fish. Elevated Ba concentrations were detected in all treatment fish tissue samples within 48 h post injection. Residual Ba concentrations decreased throughout the remainder of the 8 week experimental period in all tissues except bone. The BaCl(2) injection had no significant effects on measured whole blood variables or on the plasma concentrations of steroid hormones. Enriched Ba stable isotopes can therefore be used at low dosages to mark larvae of commercially important marine fishes, without adverse effects on the health of the fishes or on humans who may consume them.