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Conclusion: Variability of GGEMG at sleep onset is associated with apnea severity in OSA patients. At sleep onset, a lower decline in GGEMG might suggest a more severe OSA.Objective: The goal of this study was to evaluate genioglossus (GG) activation in the Chinese population at early sleep onset, and clarify the relationship of GG activation and the apnea severity in patients with Obstructive Sleep Apnea (OSA).Methods: Thirty-five OSA patients and 10 normal controls underwent overnight polysomnography with synchronous genioglossus electromyography (GGEMG) using intra-oral electrodes. The upper airway (UA) anatomy was evaluated by three-dimensional computer tomography (3D-CT) in all subjects.Results: The average GGEMG and tonic GGEMG were higher in the apnea patients than in the normal controls during wakefulness and early sleep onset period (three breaths) (p < 0.01). Eight OSA patients had increased GGEMG at sleep onset and 27 patients had decreased GGEMG values. Between the two groups, there were significant differences in the apnea-hypopnea index (AHI), minimal cross-sectional airway area (mCAS) and minimal lateral airway dimension (mLAT) at velopharynx (p < 0.05). The change in GGEMG, phasic GGEMG and tonic GGEMG from awake to sleep showed positive correlations with AHI and negative correlations with velopharynx (mLAT and mCAS) (p < 0.05). [ABSTRACT FROM PUBLISHER]

Huang Y, Liu Y-H. Effects of phytoestrogens on genioglossus contractile properties in ovariectomized rats exposed to chronic intermittent hypoxia may be independent of their estrogenicity. Eur J Oral Sci 2011; 119: 128-135. © 2011 Eur J Oral Sci Chronic intermittent hypoxia (CIH) is a frequent feature of obstructive sleep apnea/hypopnea syndrome (OSAHS), and it may alter upper airway muscle endurance. We have previously reported the positive effects of estrogen on genioglossus fatigue resistance in rats. Our present study was designed to evaluate the effects of two phytoestrogens - genistein and coumestrol - on genioglossus contractile function and estrogen receptor (ER) expression in female rats exposed to CIH. Eight-wk-old female rats were ovariectomized and exposed to CIH for 5 wk. Genistein and coumestrol, respectively, were administered by intraperitoneal injection, at a dose of 2.5 mg kg d, during the last 4 d of exposure to CIH. The contractile properties of the genioglossus were measured. Real-time RT-PCR and western blotting were performed to determine the expression of ERs in the genioglossus. Phytoestrogens were found to significantly increase genioglossus fatigue resistance, the effect of genistein being more powerful than that of coumestrol. However, higher levels of ER mRNA and protein were detected in the coumestrol group than in the genistein group. We conclude that phytoestrogens, especially genistein, could improve the endurance of the genioglossus muscle in ovariectomized rats exposed to CIH, and this effect is, in part, not related to its estrogenic action. [ABSTRACT FROM AUTHOR]