Vitamin D metabolites and extracellular calcium regulate calcium currents in hemocytes of land snails.
Intracellular exchangeable calcium and calcium efflux were investigated in cultured amoebocytes of land snails. Low extracellular calcium concentration (0.32 mM) initiated a rapid increase of outward calcium currents and decrease of intracellular exchangeable calcium. On the other hand, high extracellular calcium concentration (32 mM) increased intracellular exchangeable calcium. Actions of vitamin D metabolites were most prominent under non-physiological concentrations of extracellular calcium. Metabolite E activated a calcium pump while 25-hydroxy-vitamin D3 deactivated the pump. Both metabolites increased calcium transfer into stored pools.
Biochemistry Department, Weizmann Institute of Science, Rehovot, Israel.
L
L
Kriajev
S
S
Edelstein
D000818:Animals; D002112:Calcifediol / Q000494:pharmacology*; D002117:Calcitriol / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism* / Q000494:pharmacology; D015220:Calcium Channels / Q000187:drug effects / Q000378:metabolism*; D003594:Cytoplasmic Granules / Q000187:drug effects / Q000378:metabolism; D006434:Hemocytes / Q000187:drug effects / Q000378:metabolism*; D066298:In Vitro Techniques; D007700:Kinetics; D012908:Snails; D013997:Time Factors
D015220:Calcium Channels; D002117:Calcitriol; D002112:Calcifediol; D002118:Calcium