Differential effects of aluminium, lead and mercury on inositol 1,4,5-trisphosphate mediated Ca sup 2+ release from rat brain microsomes

Conference · Mon Mar 11 00:00:00 EST 1991 · FASEB Journal (Federation of American Societies for Experimental Biology); (United States)

OSTI ID:5905049

Pentyala, S N; Sekhon, B S; Trottman, C H; Desaiah, D ^[1]

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1. Univ. of Mississippi, Jackson (United States)

Inositol 1,4,5-trisphosphate (IP{sub 3}), an intracellular messenger, releases Ca{sup 2+} from microsomes. Ca{sup 2+} plays a major role in regulating various cellular events like neural transmission and regulation of hormones and growth factors. Aluminium (Al), Lead (Pb) and Mercury (Hg) were reported to alter Ca{sup 2+}-regulated events thereby causing neurotoxicity. Hence, the authors made an attempt to characterize IP{sub 3} mediated Ca{sup 2+} release from rat brain microsomes under the influence of Al, Pb and Hg. Different concentrations of metals were taken over a period of time and their effects on IP{sub 3} mediated Ca{sup 2+} release from microsomes were monitored using fura-2 technique. All the three metals were found to inhibit IP{sub 3} mediated Ca{sup 2+} release in a concentration dependent manner, Pb being more potent. The order of potency of these three metals was Pb > Hg > Al. Except for Al, both Hg and Pb independently released Ca{sup 2+} from microsomes. Uptake of Ca{sup 2+} into the microsomes was also inhibited by all the three metals, Hg being more potent. A 100% inhibition of Ca{sup 2+} uptake was observed with 10 {mu}M of Hg, and a 50% inhibition of Ca{sup 2+} uptake was observed with 0.5 and 80{mu}M of Pb and Al respectively. These results suggest that neurotoxicity exerted by Al,Pb and Hg may be due to the interference of these metals with IP{sub 3} mediated Ca{sup 2+} release.

• DOE Contract Number: FG05-86ER75274
• OSTI ID: 5905049
• Report Number(s): CONF-9104107-; CODEN: FAJOE
• Journal Information: FASEB Journal (Federation of American Societies for Experimental Biology); (United States), Vol. 5:4; Conference: 75. annual meeting of the Federation of American Societies for Experimental Biology (FASEB), Atlanta, GA (United States), 21-25 Apr 1991; ISSN 0892-6638
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALUMINIUM
TOXICITY
CALCIUM COMPOUNDS
SECRETION
LEAD
MERCURY
PHOSPHOLIPIDS
BIOCHEMICAL REACTION KINETICS
BRAIN
INHIBITION
METABOLISM
MICROSOMES
RATS
ALKALINE EARTH METAL COMPOUNDS
ANIMALS
BODY
CELL CONSTITUENTS
CENTRAL NERVOUS SYSTEM
ELEMENTS
ESTERS
KINETICS
LIPIDS
MAMMALS
METALS
NERVOUS SYSTEM
ORGANIC COMPOUNDS
ORGANIC PHOSPHORUS COMPOUNDS
ORGANS
REACTION KINETICS
RIBOSOMES
RODENTS
VERTEBRATES
560300* - Chemicals Metabolism & Toxicology