EFFECT OF AMBROXOL ON CYTOSOLIC CALCIUM RISE IN HUMAN POLYMORPHONUCLEAR LEUKOCYTES AFTER STIMULATION WITH N-FORMYL-METHIONYL-LEUCYL-PHENYLALANINE AND CONCANAVALIN-A

Ambroxol has been shown to influence some functions of human polymorph onuclear leukocytes (PMNL). In this study we investigated the effect o f this drug on the 10(-7)M FMLP- and 100 mu g/ml Con A- induced rise o f intracellular free calcium concentration ([Ca2+]), in human PMNL. Pr eincubation of cells with 100 mu M ambroxol enhanced their Ca2+ respon se to FMLP. The maximal increment of [Ca2+], was 388.5+/-106.7 nM vers us 242.6+/-92.5 nM (P<0.01) observed for PMNL without drug. However, t he PMNL Ca2+ response to second stimulation with FMLP (5 min after the first) mas inhibited by ambroxol. The rise of [Ca2+], decreased 1.7-f old from 85.5+/-18.5 to 50.9+/-12.0 nM (p<0.01). When cells were activ ated by Con A with 3.3 mu g/ml cytochalasin B, ambroxol revealed inhib itory effect on PMNL Ca2+ response. The [Ca2+], increased only by 135. 7+/-30.8 nM versus 215.6+/-41.5 nM (p<0.01) found in PMNL without drug . Ambroxol alone did not alter the cell viability and [Ca2+], in resti ng PMNL. Our study gives evidences that ambroxol a mucolytic drug can modulate the Ca2+ response which regulates various subcellular process es in human PMNL.