NIFEDIPINE INHIBITS MAGNETIC FIELD-INDUCED LYSOSOMAL DEGRANULATION

Human peripheral polymorphonuclear leukocytes were exposed to static magnetic fields of variable intensity (0-1.0 T). Following exposure for 30 minutes, the cells were centrifuged and the supernatant was assayed for release of lactate dehydrogenase, a marker of cytotoxicity. Up to 9% of the cells' total content of this lysosomal enzyme was released after exposure to a 1.0-T magnetic field. Significantly less degranulation occurred following pretreatment with 5-mu-M nifedipine, a calcium channel antagonist. Calcium channel antagonists may serve as magnetoprotective agents against magnetic field-induced changes in Ca2+ -dependent cellular processes.