Abstract: The aim was to determine the relationship between plasma concentrations of Vasoactive intestinal peptide (VIP) and sleep quality in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). Retaining manometric tube in radial artery and polysomnography (PSG) were done synchronously in 12 patients with OSAHS who was diagnosed by whole-night PSG. Blood specimen were extracted before sleep, during NREM sleep and REM sleep and the next morning to detect plasma concentrations of VIP with Radioimmunoassay(RIA) method. Results: 1) The VIP values before sleep and in the morning were positively correlated with sleep efficacy(the ratio of total sleep time to total record time, r=0.591,P<0.05) and negatively with Arousal/TRT(the ratio of time in arousal to total sleep time, r=-0.586,P<0.05);The VIP values before sleep were regarded as baseline, the changes in VIP values in NREM sleep were negatively correlated with the ratio of time in stageⅠ+Ⅱto total sleep time(Ⅰ+Ⅱ/TST,r=-0.656,P<0.05) and positively correlated with the ratio of time in REM sleep to total sleep time(REM/TST,r=0.705,P<0.01) and those in REM sleep were also positively correlated with REM/TST(r=0.609,P<0.05); 2) The VIP values in different period were positively correlated with the longest time of sleep apnea and apnea-hypopnea index(AHI), but not with hypoxia. In conclusion, VIP may be involved in regulating the sleep in patients with OSAHS.

Key words: obstructive sleep apnea-hypopnea syndrome, vasoactive intestinal peptide, sleep stage