[Distributing and changes of NO and calcitonin gene-related peptide in pharyngeal tissues and plasma in obstructive sleep apnea and hypopnea syndrome].

Objective: To explore the distributing and changes of nitric oxide (NO) and calcitonin gene-related peptide (CGRP) in obstructive sleep apnea and hypopnea syndrome (OSAHS).

Methods: This study investigated the content of NO and CGRP in plasma and in pharyngeal tissues of OSAHS subjects. Moreover, the distribution of NOS and CGRP in pharyngeal tissues was researched using method of immunohistochemistry.

Results: (1) Plasma NO level in control group was higher than in mild OSAHS group and in serious OSAHS group, P < 0.001. There was a significant increase in plasma CGRP after UPPP (P < 0.001), and the plasma CGRP level in control group was as high as that in after UPPP group (P > 0.05) NO level in pharyngeal tissue of OSAHS increased significantly, P < 0.001), but CGRP level decreased markedly, P < 0.001. (2) Immunohistochemistry change about NOS: there was a feeble positive expression in mucosa squamous epithelium of OSAHS and powerful positive expression in some salivary glandular epithelium, striated muscle cells, vascular wall/small vascular wall and epithelium of glandular duct of OSAHS. (3) Immunohistochemistry change about CGRP: There were diffusible positive markings in striated muscle cells and most cilium columnar epithelium in OSAHS, and negative expressions in other sites.

Conclusions: (1) Circulating NO and CGRP are suppressed in OSAHS, and reversible promptly after UPPP. Further more, The content of NO in pharyngeal tissues increases significantly and that of CGRP decreases markedly. (2) The distribution of NOS and CGRP in pharyngeal tissue changes apparently according to sites.