Cadmium inhibition of Ca sup 2+ uptake in rainbow trout gills

Journal Article · Sat Aug 01 04:00:00 EDT 1987 · American Journal of Physiology; (USA)

OSTI ID:5025954

Verbost, P M; Flik, G; Lock, R A.C.; Wendelaar Bonga, E E ^[1]

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1. Catholic Univ., Nijmegen (Netherlands)

The effects of cadmium (Cd{sup 2+}) on calcium (Ca{sup 2+}) transport in the gills of rainbow trout (Salmo gairdneri) were studied. The gill epithelium of freshwater fish represents a model for a Ca{sup 2+}-transporting tight epithelium. Unidirectional {sup 45}Ca{sup 2+} fluxes in the gills were estimated in an isolated saline-perfused heat preparation. {sup 45}Ca{sup 2+} influx was not affected when up to 10 {mu}M Cd were added to the ventilatory water at the start of flux determinations (in vitro exposure). However, after 16 h in vivo preexposure of the fish to 0.1 {mu}M Cd in the water, a 79% inhibition of Ca{sup 2+} influx was observed. Ca{sup 2+} efflux was not affected when up to 10 {mu}M Cd were added to the ventilatory water during the flux determination. Ca{sup 2+} efflux in fish preexposed to 0.1 {mu}M Cd for 16 h was also not affected; a preexposure to 1 {mu}M Cd, however, resulted in a 173% increase in Ca{sup 2+} efflux rates. Tracer retention in the gill tissue indicated that both Ca{sup 2+} and Cd{sup 2+} enter the gill epithelium via a lanthanum (La{sup 3+})-inhibitable pathway. It is concluded that Cd{sup 2+} readily enters the branchial epithelial cells, similarly as Ca{sup 2+} does via La{sup 3+}-sensitive apical Ca{sup 2+} channels. The inhibitory action of Cd{sup 2+} on transepithelial Ca{sup 2+} influx seems to result from an inhibition of the basolateral Ca{sup 2+} transport, occurring after a critical intracellular Cd{sup 2+} concentration has been reached.

• OSTI ID: 5025954
• Journal Information: American Journal of Physiology; (USA), Journal Name: American Journal of Physiology; (USA) Vol. 253:2; ISSN 0002-9513; ISSN AJPHA
• Country of Publication: United States
• Language: English

Related Subjects

550201 -- Biochemistry-- Tracer Techniques
560300* -- Chemicals Metabolism & Toxicology
59 BASIC BIOLOGICAL SCIENCES
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
ALKALINE EARTH ISOTOPES
ALKALINE EARTH METAL COMPOUNDS
ANIMAL TISSUES
ANIMALS
AQUATIC ORGANISMS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL EFFECTS
BODY
CADMIUM COMPOUNDS
CALCIUM 45
CALCIUM COMPOUNDS
CALCIUM ISOTOPES
CELL CONSTITUENTS
CELL MEMBRANES
DAYS LIVING RADIOISOTOPES
ELEMENTS
EVEN-ODD NUCLEI
FISHES
GILLS
INHIBITION
INTERMEDIATE MASS NUCLEI
ISOTOPES
LANTHANUM
MEMBRANE TRANSPORT
MEMBRANES
METALS
NUCLEI
PERFUSED TISSUES
RADIOISOTOPES
RARE EARTHS
RESPIRATORY SYSTEM
TISSUES
TROUT
UPTAKE
VERTEBRATES