慢性间歇低氧对大鼠颏舌肌超微结构和线粒体功能的影响

目的 探讨慢性间歇低氧(CIH)对大鼠颏舌肌细胞超微结构及线粒体功能的影响及脂联素(Ad)的干预作用.方法 健康雄性Wistar大鼠39只,随机分成健康对照组(A)、CIH组(B)、CIH加Ad干预组(C),每组13只.A组大鼠保持呼吸空气,B组与C组均接受CIH环境(CIH 8 h/d,共5周),但C组同时经静脉注射...

Influence of chronic intermittent hypoxia on ultrastructure and mitochondrial function of rat genioglossal cells

Objective To investigate the effect of chronic intermittent hypoxia （CIH） on rat genioglossal ultrastructure and mitochondrial function as well as the intervention role of adiponectin （Ad）. Methods Thirty-nine healthy male Wistar rats were randomly divided into three groups： normal control group（A）, CIH group（B） and CIH＋Ad group（C）, with 13 rats in each group. Rats in group A kept breathing normal air, while rats in both groups B and C were fed in the same CIH environment （CIH 8 h/day for successive 5 weeks）. However, rats in group C were given intravenous Ad supplement at the dosage of 10 p.g, twice a week for 5 weeks. At the end of experiment （day 35）, the serum Ad levels, the genioglossal ultrastructure, and the mitochondrial State 3 respiratory rates（ST3）, state 4 respiratory rates （STn）and activities of respiratory chain complexes I and IV in mitochondrion of genioglossal cells were compared among different groups. Results （1） Serum Ad level was significantly lower in group B than in group A （1108_＋112） vs （2240_＋1210） ~tg/L, P〈0.01]. Serum Ad level in group C （1889_＋1190） Ix g/L] was significantly higher than that in group A, but lower than that in group B （P〈0.01）. （2） In group B, there were significant genioglossal ultrastructural pathological changes, such as myofibrile discontinuities, lysis of myofilament, edema of mitochondria and disruption of cristae, vacuolus and lysis of some mitochondria. These pathological changes were less significant in group C. （3） The genioglossal mitochondrial ST3, ST4, respiratory control ratio （RCR） were the lowest in group B but highest in group A, with a significant difference in ST3 and RCR among three groups （all P〈0.01）. The mitochondrial ST4 was （15.2±2.5）, （12.9±2.0）, and （13.5±2.3） p.mol/（min · g）in groups A,B and C,respectively, with a statistical difference between groups A and B （P〈0.05）, but no difference between groups C and B, or groups A and C. （4） The concentrations of mitochondrial respiratory chain complexes I and IV in group B （35.7±1.7） mmol/（min·g） and （2.4±0.1） μmol/（min·g） respectively] were the lowest, and became higher in group C （37.2±1.9） mmol/（min.g） and （2.5±0.1） μ mol/（min · g） respectively] and group A （39.0±1.3） mmol/（min · g） and （2.8±0.1） gmol/（min · g）, respectively], with a significant difference between group A and group B （P〈0.01）, between group C and group B （P〈0.05）, as well as between group C and group A （P〈0.05）. Conclusion CIH could lead to hypoadiponectinemia,impaired genioglossal ultrastructure and mitochondrial dysfunction. Since such changes could be partially improved by supplement of adiponectin, it suggests that hypoadiponectinemia be involved in CIH-induced impairment of genioglossal ultrastructure and energy metabolism.