Intracellular free magnesium in human lymphocytes and the response to lectins.
1. Intracellular free [Mg2+] was measured in human peripheral blood lymphocytes using a fluorimetric method based on the dye furaptra. It was necessary to correct for the extracellular leakage of the dye by using either 10 mmol/l EDTA or 0.05 mmol/l Mn2+. 2. As the proliferative response of lymphocytes to mitogenic lectins has been linked to a dependence on extracellular Mg2+, the intracellular [Mg2+] was studied in lymphocytes stimulated with various mitogenic and non-mitogenic lectins. 3. Only lymphocytes treated with phytohaemagglutinin-L, a leucoagglutinin from Phaseolus vulgaris that binds to tri- and tetra-antennary complex glycoproteins, showed a marked increase in intracellular [Mg2+]. This effect was partially inhibited by N-acetylgalactosamine. The stimulation by different lectins of the incorporation of [3H]-thymidine into lymphocytes was not correlated to the changes in intracellular [Mg2+]. 4. The proliferative response of lymphocytes to lectins is therefore not wholly dependent on a rise in intracellular [Mg2+].
Ng
L L
LL
Department of Pharmacology, Leicester Royal Infirmary, UK.
Davies
J E
JE
Garrido
M C
MC
D001572:Benzofurans; D002118:Calcium / Q000378:metabolism; D002455:Cell Division / Q000187:drug effects; D005456:Fluorescent Dyes; D005470:Fluorometry / Q000379:methods; D016257:Fura-2 / Q000031:analogs & derivatives*; D006801:Humans; D007424:Intracellular Fluid / Q000378:metabolism*; D037102:Lectins / Q000494:pharmacology*; D008214:Lymphocytes / Q000187:drug effects / Q000378:metabolism*; D008274:Magnesium / Q000378:metabolism*; D010080:Oxazoles; D013268:Stimulation, Chemical
D001572:Benzofurans; D005456:Fluorescent Dyes; D037102:Lectins; D010080:Oxazoles; C058776:2-(2-(5-carboxy)oxazole)-5-hydroxy-6-aminobenzofuran-N,N,O-triacetic acid; D008274:Magnesium; D002118:Calcium; D016257:Fura-2