Intrinsic properties of rostral ventrolateral medulla presympathetic and bulbospinal respiratory neurons of juvenile rats are not affected by chronic intermittent hypoxia

摘要: The presympathetic neurons in the rostral ventrolateral medulla (RVLM) are considered to be source of sympathetic activity, and there is experimental evidence that these cells present intrinsic autodepolarization. There also an important respiratory neuronal population located RVLM/Botzinger complex (BotC) corresponds augmenting expiratory (aug-E), which send projections phrenic nucleus spinal cord. However, pacemaker activity properties aug-E had not been evaluated brainstem slices juvenile rats (postnatal day 35). Chronic intermittent hypoxia (CIH) a sympathetic-mediated hypertension model, seems produce associated increase neurons. In this study, we effects CIH on RVLM/BotC nucleus-projecting (aug-E) We observed all presented spontaneous action potential firing (n = 18), was abolished by ionotropic receptor antagonism. addition, exposure 10 days produced no changes their passive properties, pattern or excitability. Most control conditions (13 15 neurons), characteristic preserved after blocking fast synaptic transmission (12 clearly demonstrating activity. frequency discharge excitability study shows that: (i) it possible record electrophysiological from rats; (ii) these characteristics pacemakers; (iii) their were altered chronic hypoxia.