John Greer

Biography

John Greer is an assistant professor belongs to the department of Physiology from the university of Alberta.

Research Interest

Research Description Our laboratory performs basic physiological studies directed toward providing fundamental insights into the development of the neuromuscular control of respiration while having relevance to clinical respiratory disorders of the neonate. We are affiliated with the Perinatal Respiratory Research Group and the Centre for Neuroscience. Pathogenesis and Etiology of Congenital Diaphragmatic Hernia studying the mechanisms controlling motor axon guidance towards their target musculature. examining the events underlying the formation of muscle from the time of somitic muscle precursors migration through to myotube formation. examining the pathogenesis and etiology of congenital diaphragmatic hernia (CDH). Medical significance: Our proposed research has been designed to determine the normal developmental processes underlying phrenic nerve-diaphragm formation and then to establish which aspects maldevelop in a well-established rodent model of CDH. CDH is a developmental anomaly characterized by large regions of the diaphragm failing to form. Consequently, the developing viscera invade the thoracic cavity, occupying space normally reserved to accommodate the growing lung. As a result, newborns with CDH (~1:3000 births; ~50% mortality) suffer from a combination of pulmonary hypoplasia, pulmonary hypertension and surfactant deficiency. Methods: Immunohistochemistry; in situ hybridization; whole embryo cultures; use of null-mutant mice; examining retinoid signaling pathways in cells lines and transgenic mice. Neural Control of Perinatal Respiration examining the development of the respiratory generating centre (preBötzinger complex) in rodent models. This includes studies of mutant mouse models with respiratory dysfunction. examining the neuromodulation of perinatal respiration Medical significance: We examine the electrophysiological properties and neuromodulation of perinatal respiratory rhythmogenesis towards understanding the basis for central apneas. Methods: Whole cell and perforated patch-clamp recording from fluorescently tagged preBötzinger neurons; in vitro medullary slice and brainstem-spinal cord preparations; perinatal rat and mutant mouse models.