strychnine and Sleep-Apnea-Syndromes

This article reviews recent studies on the importance of glycine receptors for both the spontaneous and the reflex respiratory modulation of the laryngeal abductors and adductors. Our findings show that strychnine blockade of glycine receptors within the brainstem changes the eupneic three-phase respiratory pattern into two phases. This has major implications for glottal control: (i) the inspiratory glottic abduction and early expiratory adduction were both compromised--a finding mimicked by 5% hypoxia; (ii) closure of the glottis during defensive upper airway reflexes became intermittent and the reflex apnoea reversed to sustained inspiratory discharge. Based on these data, we predict that periods of prolonged hypoxia, such as those that occur during sleep apnoeas, will constrain inspiratory glottic abduction thereby impeding inhalation.

Topics: Airway Resistance; Animals; Brain Stem; Glottis; Humans; Hypoxia; Mammals; Pulmonary Ventilation; Receptors, Glycine; Sleep Apnea Syndromes; Strychnine

Topics: Diaphragm; Electromyography; Humans; Muscle Hypotonia; Muscles; Pharyngeal Muscles; Sleep Apnea Syndromes; Strychnine