Phrenic nerve, arterial blood pressure, and respiratory recordings for phrenic long term facilitation protocol.
Study purpose: The goal of the study is to characterize the impact of low vs. high-dose intermittent hypoxia preconditioning on phrenic capacity and expression of plasticity (phrenic long term facilitation) in rats with chronic cervical spinal cord injury.
Data collection: Electrophysiological datawere collected in a terminal preparation, consisting of bilateral phrenic neurograms, arterial blood pressure, end-tidal CO2, tracheal pressure and periodic assessments of arterial blood gases.
Primary conclusion: None stated
Experimental Design: Rats were assigned to one of 4 experimental groups: (1) INTACT Nx28; (2) C2Hx Nx28; (3) C2Hx dAIH; or (4) C2Hx IH28-2/2. INTACT refers to rats that did not receive any surgery/spinal cord injury. C2Hx refers to rats that received a left lateral spinal cord hemisection at the C2 level of the spinal cord. Beginning 8 weeks after injury (or the matched time point in intact controls), rats were exposed to 28 days of either continuous normoxia (Nx 28; 21% for 8 hours/day), low-dose, acute intermittent hypoxia (dAIH28; 10, 5 minute episodes of 10.5% O2 with 5 minute normoxic intervals), or high-dose, chronic intermittent hypoxia simulating moderate sleep apnea (IH28-2/2). The day after exposures were completed, terminal neurophysiological recordings were performed to assess bilateral phrenic nerve capacity (under baseline and maximal chemoreflex stimulated conditions) and plasticity (moderate acute intermittent hypoxia-induced phrenic long term facilitation).
Completeness: Study Complete. Related study Phrenic Nerve Immunohistochemistry
Subjects & Samples: Adult male Sprague-Dawley rats (n=44) were used for this study. Bilateral phrenic activity (amplitude and frequency), blood pressure (systolic, diastolic and mean arterial pressures) and heart rate are analyzed at baseline, H1, H2, H3, at 15, 30, 60 and 90 minutes post hypoxia, and during maximal chemoreceptor stimulation.
Primary vs derivative data: The primary folder contains electrophysiology recordings (smrx) from multiple anesthetized, paralyzed, vagotomized and pump-ventilated rat preparations. This study does not contain a derivative folder.
Important notes: This study contains a Docs file, which consist of a csv formatted document with blood gas data for each subject.
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