ABSTRACT
Obstructive sleep apnea (OSA) is a condition characterized by repeated episodes of pharyngeal closure during sleep. The purpose of this chapter is to provide a general overview of the histological, biochemical, and physiological features of upper airway muscle function in OSA. Because of their importance in upper airway obstructive syndromes, most notably OSA, upper airway muscle physiology has received considerable attention during the last 20 years, and several excellent reviews have been published. The reader is referred to these for detailed discussions of sleeprelated changes in muscle activity patterns and neural control (1) and the potential role of such changes in OSA (1,2). In this chapter we will review accumulating evidence that pharyngeal dilator muscle hyperactivity in OSA may lead to adaptive remodeling as well as potentially injurious alterations in the intrinsic properties of these muscles.
