Chronic exposure to cadmium did not impair vitamin D metabolism in monkeys

Journal Article · Wed Jun 01 00:00:00 EDT 1988 · Environ. Res.; (United States)

DOI:https://doi.org/10.1016/S0013-9351(88)80058-6· OSTI ID:7090560

Kawashima, H; Nomiyama, H; Nomiyama, K

Vitamin D metabolism in primates with chronic exposure to cadmium was studied in relation to Itai-Itai disease. In a series of experiments, crab-eating monkeys were fed cadmium-contaminated rice (1.33 ..mu..g Cd/g) or a diet containing 3 ..mu..g/g cadmium chloride for 6 years. These treatments had no effect on the 1,25-dihydroxyvitamin D (1,25(OH)/sub 2/D), 24,25-dihydroxyvitamin D(24,25(OH)/sub 2/D), and 25-hydroxyvitamin D(25(OH)D) in the serum. No indication of renal dysfunction was observed. In another series of experiments, rhesus monkeys were fed a diet containing 3, 10, 30, or 100 ..mu..g/g cadmium for 9 years. Serum vitamin D metabolites and renal production of 24,25(OH)/sub 2/D also remained unchanged. In contrast, renal 25(OH)D-1-hydroxylase (1-hydroxylase), which is responsible for the production of 1,25(OH)/sub 2/D, seemed to be suppressed in the animals fed 30 or 100 ..mu..g/kg cadmium-contaminated diet (no statistical significance). These animals had indications of mild renal dysfunction, and there was a strong negative correlation between 1-hydroxylase and urinary concentration of either protein or ..beta../sub 2/-microglobulin. These data suggest a slight chance in the total enzyme activity, possibly due to mild renal dysfunction. Since substrate (25(OH)D) concentration is much lower and thus rate-limiting in vivo as compared with that in vitro assay system used in this study, the slight change of enzyme activity would not have been sufficient to affect the serum level of 1,25(OH)/sub 2/D. No skeletal abnormality was observed in any of these animals.

• Research Organization: Jichi Medical School, Tochigi-ken (Japan)
• OSTI ID: 7090560
• Journal Information: Environ. Res.; (United States), Vol. 46:1
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
CADMIUM
BIOLOGICAL EFFECTS
VITAMIN D
METABOLISM
CHRONIC EXPOSURE
DIET
ENZYME ACTIVITY
ETIOLOGY
INGESTION
KIDNEYS
MONKEYS
SKELETAL DISEASES
ANIMALS
BODY
DISEASES
ELEMENTS
INTAKE
MAMMALS
METALS
ORGANS
PRIMATES
VERTEBRATES
VITAMINS
560300* - Chemicals Metabolism & Toxicology