Role of substance P in the laryngeal chemoreflex

摘要: The laryngeal chemoreflex (LCR) is a potentially life-threatening reflex that elicited in immature animals by the topical application of water to mucosa. response characterized immediate apnea and adduction delayed cardiovascular instability. cardiorespiratory changes LCR may be life-threatening, particularly very such as piglets under weeks age. afferent efferent limbs are mediated through vagus nerve, but neuromediators responsible for have not yet been clearly elucidated. Previous agonist antagonist studies dogs demonstrated substance P, sensory tachykinin, mediates esophagolaryngeal adductor distal esophageal nerve stimulation. This study was conducted determine if P also plays role mediating LCR. compared before after treatment with intravenous (Pfizer CP-96,345-1) eight (mean 27.7 days age). responses following administration tachykinins neurokinin A, B were assessed. Pretreatment did alter LCR's duration (p >.10), response, or early change mean arterial pressure although maximal heart rate significantly altered <.01). Intravenous A. reproduce respiratory We conclude key neurotransmitters