Toxic effects of arsenic (III) on some hematopoietic and central nervous system variables in rats and guinea pigs.
OBJECTIVE
To evaluate the effects of arsenic (III) exposure on porphyrin metabolism and the central nervous system supplemented with data on the effect of hepatic and renal tissues of rats and guinea pigs.


METHODS
Rats and guinea pigs were exposed to 10 or 25 ppm arsenic in drinking water for 16 weeks.


RESULTS
Following chronic arsenic (III) exposure, delta-aminolevulinic acid dehydratase activity in blood showed a significant reduction as did the total cell counts (RBC and WBC) and reduced glutathione with increased urinary delta-aminolevulinic acid. Zinc protoporphyrin, a sensitive indicator of iron deficiency and impairment of heme biosynthesis, showed a significant increase in arsenic exposure. The hepatic delta-aminolevulinic acid dehydratase and delta-aminolevulinic acid synthetase activity increased in chronic arsenic (III) exposure in rats and guinea pigs. Significant changes in the steady-state level of three major neurotransmitters, dopamine, norepinephrine, and 5-hydroxytryptamine, and monoamine oxidase were observed following chronic arsenic (III) exposure.


CONCLUSIONS
At low doses (10 and 25 ppm in drinking water), the effects of arsenic on hematopoietic indices and whole-brain neurotransmitter concentrations were more prominent in guinea pigs than in rats with some variability in the dose response.
Kannan
G M
GM
Defense Research and Development Establishment, Gwalior, India.
Tripathi
N
N
Dube
S N
SN
Gupta
M
M
Flora
S J
SJ
D000624:5-Aminolevulinate Synthetase / Q000378:metabolism; D000622:Aminolevulinic Acid / Q000097:blood / Q000652:urine; D000818:Animals; D018053:Arsenites / Q000493:pharmacokinetics / Q000633:toxicity*; D015306:Biogenic Monoamines / Q000378:metabolism; D001772:Blood Cell Count; D001773:Blood Cells / Q000187:drug effects; D001921:Brain / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004326:Drinking; D005978:Glutathione / Q000097:blood; D006168:Guinea Pigs; D006413:Hematopoietic System / Q000187:drug effects*; D007668:Kidney / Q000187:drug effects / Q000378:metabolism; D008099:Liver / Q000187:drug effects / Q000201:enzymology; D008297:Male; D000623:Porphobilinogen Synthase / Q000097:blood; D011524:Protoporphyrins / Q000097:blood; D051381:Rats; D017670:Sodium Compounds / Q000493:pharmacokinetics / Q000633:toxicity*; D014881:Water Supply
D018053:Arsenites; D015306:Biogenic Monoamines; D011524:Protoporphyrins; D017670:Sodium Compounds; C017803:zinc protoporphyrin; C017947:sodium arsenite; D000622:Aminolevulinic Acid; D000624:5-Aminolevulinate Synthetase; D000623:Porphobilinogen Synthase; D005978:Glutathione