Categories: 動脈硬化血管瘤主動脈剝離栓塞高血壓心肌梗塞孫學軍醫師文獻

氫氣對新生兒腦缺血沒有作用？

這個研究是美國的一個實驗室與我們合作的論文。我一直關注這個研究。可惜發現的結果與我們的研究不一致。為什麼這樣，可能的原因是，呼吸的濃度高（2.9%），模型損傷比較重。明顯比我們的損傷重。但這個解釋似乎牽強。最近據說在手術損傷方面也沒有發現治療效果。真不可思議。值得慶幸的是，他們證明在大鼠缺血模型有效，但沒日本報導的效果好。

Hydrogen gas is ineffective in moderate and severe neonatal hypoxia–ischemia rat models

References and further reading may be available for this article. To view references and further reading you must purchase this article. Gerald A. Matchett ^a, Nancy Fathali ^b, Yu Hasegawa ^b, Vikram Jadhav ^b, Robert P. Ostrowski ^b, Robert D. Martin ^a, Ihab R. Dorotta ^a, Xuejun Sun ^dand John H. Zhang^a^,^b^,^c^,^,

^aDepartment of Anesthesiology, Loma Linda University, Loma Linda, California, USA

^bDepartment of Physiology and Pharmacology, Loma Linda University, Loma Linda, California, USA

^cDivision of Neurosurgery, Loma Linda University, Loma Linda, California, USA

^dThe Second Military Medical University, Shanghai, China

Accepted 12 December 2008.

Available online 10 January 2009.

Abstract

Hydrogen gas (H ₂) has been shown to ameliorate brain injury in experimental adult rat focal ischemia and in amild neonatal hypoxia–ischemia (HI, 90 min hypoxia) rat model. In this study we tested H ₂in moderate (120 min hypoxia) and severe (150 min hypoxia) neonatal HI rat models. We hypothesized that H ₂would improve outcomes after neonatal HI by scavenging free radicals. Two hundred (200) unsexed Sprague–Dawley rats at day 10 of life (p10) underwent neonatal HI with the Rice –Vannucci model. Multiple treatment protocols were studied, including pre-ischemic treatment, intra-ischemic treatment, and post-ischemic treatment (Sham n = 32, HI n = 82, HI + H ₂ n = 86). We also tested H ₂in middle cerebral artery occlusion (MCAO) in adult rats (MCAO n = 9, MCAO + H ₂ n = 7) for comparison. Analysis at 24 h included infarction volume, measurement of brain concentration of malondialdehyde (MDA) (an end-product of lipid peroxidation), daily weight, Nissl histology, and mortality. In moderate and severe neonatal HI models, hydrogen gas therapy (2.9% concentration H ₂) was not associated with decreased volume of infarction or decreased concentration of MDA. H ₂gas pretreatment (2.9%) was associated with increased infarction volume in neonatal HI. In MCAO in adult rats, H ₂gas therapy demonstrated a trend of beneficial effect. Exposure of H ₂gas to non-ischemic neonates resulted in a significant increase in brain concentration of MDA. We conclude that 2.9 % H ₂gas therapy does not ameliorate moderate to severe ischemic damage in neonatal hypoxia–ischemia.

Keywords: H ₂; Hydrogen gas; Free radical; Neonatal hypoxia–ischemia

Abbreviations: HI, hypoxia–ischemia; MCAO, middle cerebral artery occlusion; MDA, malondialdehyde; PBS, Phosphate buffered saline; TTC, 2,3,5-triphenyltetrazolium chloride; RCAO, Right carotid artery occlusion