Macickova Tatiana, Pecivova Jana, Nosal Radomir, Lojek Antonin, Pekarova Michaela, Cupanikova Daniela
Institute of Experimental Pharmacology, Slovak Academy of Sciences, Bratislava, Slovakia.
Neuro Endocrinol Lett. 2008 Oct;29(5):790-3.
To compare three stimuli which activate human neutrophils with different signal transduction mechanisms, in order to better localize the effect of the beta-adrenoceptor antagonist carvedilol (CARV) on superoxide generation (O2*-) and myeloperoxidase release (MPO). The effect of CARV [0.1-100 micromol/l] on O2*- generation and MPO release from isolated human neutrophils was studied after specific receptor activator N-formyl-methionyl-leucyl-phenylalanine (fMLP) and nonreceptor phorbol-12-myristate-13-acetate (PMA) and calcium ionophor (A23187) stimuli.
O2*- generation was measured as superoxide dismutase inhibitable reduction of cytochrome c and MPO release as the oxidation of o-dianisidine in the presence of hydrogen peroxide in a spectrophotometer Hewlet Packard 8452 A at respective 550 and 463 nm.
CARV had no effect on O2*- generation and MPO release in nonstimulated cells. In the concentration 10 and 100 micromol/l, it significantly decreased fMLP and PMA stimulated O2*- generation and MPO release. Incubation of neutrophils with CARV [100 micromol/l] caused significant inhibition of O2*- generation and MPO release induced by A23187. Wortmannin, a specific inhibitor of 1-phosphatidylinositol-3-kinase, inhibited significantly only fMLP stimulated O2*- generation. CARV [100 micromol/l] with wortmannin [50 nmol/l] further decreased O2*- generation after the same stimulus.
CARV decreased O2*- generation and MPO release from isolated human neutrophils both by membrane-operating stimulus - fMLP and membrane bypassing activators - PMA and A 23187. This fact, together with effect the of wortmannin, indicates that the inhibition may be attributed to the non-specific action of CARV and its interference with phospholipase D signaling pathway, which plays only a minor role in proteinkinase C stimulated O2*- generation.
比较三种通过不同信号转导机制激活人中性粒细胞的刺激物，以便更好地定位β-肾上腺素能受体拮抗剂卡维地洛（CARV）对超氧化物生成（O2*-）和髓过氧化物酶释放（MPO）的影响。在特异性受体激活剂N-甲酰甲硫氨酰亮氨酰苯丙氨酸（fMLP）、非受体佛波醇-12-肉豆蔻酸酯-13-乙酸酯（PMA）和钙离子载体（A23187）刺激后，研究了CARV[0.1-100微摩尔/升]对分离的人中性粒细胞O2*-生成和MPO释放的影响。
在惠普8452 A分光光度计上，分别于550和463纳米处，将O2*-生成测定为超氧化物歧化酶可抑制的细胞色素c还原，将MPO释放测定为在过氧化氢存在下邻联茴香胺的氧化。
CARV对未刺激细胞的O2*-生成和MPO释放无影响。在10和100微摩尔/升浓度下，它显著降低fMLP和PMA刺激的O2*-生成和MPO释放。用CARV[100微摩尔/升]孵育人中性粒细胞可显著抑制A23187诱导的O2*-生成和MPO释放。1-磷脂酰肌醇-3-激酶的特异性抑制剂渥曼青霉素仅显著抑制fMLP刺激的O2*-生成。CARV[100微摩尔/升]与渥曼青霉素[50纳摩尔/升]共同作用，在相同刺激后进一步降低O2*-生成。
CARV通过膜操作刺激物-fMLP以及膜旁路激活剂-PMA和A23187，降低了分离的人中性粒细胞的O2*-生成和MPO释放。这一事实，连同渥曼青霉素的作用，表明这种抑制可能归因于CARV的非特异性作用及其对磷脂酶D信号通路的干扰，而磷脂酶D信号通路在蛋白激酶C刺激的O2*-生成中仅起次要作用。
