Piñol-Ripoll G, Fuentes-Broto L, Millán-Plano S, Reyes-Gonzáles M, Mauri J A, Martínez-Ballarín E, Reiter R J, García J J
Department of Pharmacology and Physiology, University of Zaragoza, Zaragoza, Spain.
Neurosci Lett. 2006 Sep 11;405(1-2):89-93. doi: 10.1016/j.neulet.2006.06.031. Epub 2006 Jul 18.
Nitric oxide (NO) is a physiological neurotransmitter, a mediator of the excitatory neurotransmitter glutamate pathways that regulates several neuroendocrine functions, but excessive NO is toxic by itself and it interacts with superoxide radical (O(2)(-)) to form the peroxynitrite anion (ONOO(-)). Using rat brain homogenates, we investigated the effects of melatonin and pinoline in preventing the level of lipid peroxidation (LPO) and carbonyl contents in proteins induced by nitric oxide (NO) which was released by the addition of sodium nitroprusside (SNP). Lipid and protein peroxidation were estimated by quantifying malondialdehyde (MDA) and 4-hydroxyalkenal (4-HDA) concentrations and carbonyl contents, respectively. SNP increased MDA+4-HDA and carbonyl contents production in brain homogenates in a time and concentration dependent manner. Both, melatonin and pinoline reduced NO-induced LPO and carbonyl contents in a dose-dependent manner in concentrations from 0.03 to 3 mM and 1 to 300 microM, respectively. Under the in vitro conditions of this experiment, both antioxidants were more efficient in limiting SNP protein oxidation than lipid damage.
一氧化氮（NO）是一种生理神经递质，是兴奋性神经递质谷氨酸途径的介质，可调节多种神经内分泌功能，但过量的NO本身具有毒性，它与超氧阴离子自由基（O₂⁻）相互作用形成过氧亚硝酸根阴离子（ONOO⁻）。我们使用大鼠脑匀浆，研究了褪黑素和水合松果体素在预防由硝普钠（SNP）释放的一氧化氮（NO）诱导的脂质过氧化（LPO）水平和蛋白质羰基含量方面的作用。分别通过定量丙二醛（MDA）和4-羟基烯醛（4-HDA）浓度以及羰基含量来估计脂质和蛋白质过氧化。SNP以时间和浓度依赖性方式增加脑匀浆中MDA + 4-HDA和羰基含量的产生。褪黑素和水合松果体素均分别以0.03至3 mM和1至300 μM的浓度以剂量依赖性方式降低NO诱导的LPO和羰基含量。在本实验的体外条件下，两种抗氧化剂在限制SNP蛋白质氧化方面比脂质损伤更有效。
