一氧化碳中毒在台灣的冬天非常常見,雖然政府現在已經強制要安裝強制排氣了,不過今年冬天還是有慘劇發生,希望以後不要再有這類狀況發生了

圖文來自:nejm 

Volume 360:1217-1225  March 19, 2009  Number 12

 

Carbon monoxide (CO) diffuses quickly into the blood by way of the lungs and causes injury and an adaptive response that continue after carboxyhemoglobin levels have returned to normal. CO causes hypoxemia through the formation of carboxyhemoglobin and a leftward shift of the oxyhemoglobin dissociation curve. CO binds to heme proteins such as cytochrome c oxidase (CCO), impairing mitochondrial function and thereby contributing to hypoxia. Brain hypoxia elevates levels of excitatory amino acids, increasing brain nitrite levels and causing subsequent injury. Brain hypoxia causes oxidative stress, necrosis, and apoptosis, contributing to inflammation and injury. CO also causes inflammation by increasing levels of cytosolic heme and the heme oxygenase-1 (HO-1) protein, resulting in intracellular oxidative stress. CO binds to platelet heme proteins, causing the release of nitric oxide (•NO). Excess •NO produces peroxynitrite (ONOO), impairing mitochondrial function, which contributes to hypoxia. CO causes platelet-to-neutrophil aggregation and neutrophil degranulation, involving the release or production of myeloperoxidase (MPO), proteases, and reactive oxygen species — which cause oxidative stress, lipid peroxidation,and apoptosis. Proteases interact with xanthine dehydrogenase (XD) in endothelial cells, forming xanthine oxidase (XO), which inhibits endogenous mechanisms against oxidative stress. Lipid-peroxidation products form adducts with myelin basic protein, altering its structure, triggering a lymphocytic immunologic response, increasing microglia activation and activity, and causing neuropathologic effects. Finally, CO induces cellular stress responses such as the activation of hypoxia-inducible factor 1 (HIF-1), which can induce gene regulation. This gene regulation can be protective or can result in injury, depending on the CO dose and on host factors, which remain largely unknown. NMDA denotes N-methyl-D-aspartate, and nNOS neuronal nitric oxide synthase.

 

arrow
arrow
    全站熱搜

    快樂小藥師 發表在 痞客邦 留言(1) 人氣()