TY - JOUR
T1 - Novel whole body plethysmography system for the continuous characterization of sleep and breathing in a mouse
AU - Hernandez, A. B.
AU - Kirkness, J. P.
AU - Smith, P. L.
AU - Schneider, H.
AU - Polotsky, M.
AU - Richardson, R. A.
AU - Hernandez, W. C.
AU - Schwartz, A. R.
PY - 2012/2
Y1 - 2012/2
N2 - Sleep is associated with marked alterations in ventilatory control that lead to perturbations in respiratory timing, breathing pattern, ventilation, pharyngeal collapsibility, and sleep-related breathing disorders (SRBD). Mouse models offer powerful insight into the pathogenesis of SRBD; however, methods for obtaining the full complement of continuous, high-fidelity respiratory, electroencephalographic (EEG), and electromyographic (EMG) signals in unrestrained mice during sleep and wake have not been developed. We adapted whole body plethysmography to record EEG, EMG, and respiratory signals continuously in unrestrained, unanesthetized mice. Whole body plethysmography tidal volume and airflow signals and a novel noninvasive surrogate for respiratory effort (respiratory movement signal) were validated against simultaneously measured gold standard signals. Compared with the gold standard, we validated 1) tidal volume (correlation, R 2 = 0.87, P < 0.001; and agreement within 1%, P < 0.001); 2) inspiratory airflow (correlation, R 2 = 0.92, P < 0.001; agreement within 4%, P < 0.001); 3) expiratory airflow (correlation, R 2 = 0.83, P < 0.001); and 4) respiratory movement signal (correlation, R 2 = 0.79-0.84, P < 0.001). The expiratory airflow signal, however, demonstrated a decrease in amplitude compared with the gold standard. Integrating respiratory and EEG/EMG signals, we fully characterized sleep and breathing patterns in conscious, unrestrained mice and demonstrated inspiratory flow limitation in a New Zealand Obese mouse. Our approach will facilitate studies of SRBD mechanisms in inbred mouse strains and offer a powerful platform to investigate the effects of environmental and pharmacological exposures on breathing disturbances during sleep and wakefulness.
AB - Sleep is associated with marked alterations in ventilatory control that lead to perturbations in respiratory timing, breathing pattern, ventilation, pharyngeal collapsibility, and sleep-related breathing disorders (SRBD). Mouse models offer powerful insight into the pathogenesis of SRBD; however, methods for obtaining the full complement of continuous, high-fidelity respiratory, electroencephalographic (EEG), and electromyographic (EMG) signals in unrestrained mice during sleep and wake have not been developed. We adapted whole body plethysmography to record EEG, EMG, and respiratory signals continuously in unrestrained, unanesthetized mice. Whole body plethysmography tidal volume and airflow signals and a novel noninvasive surrogate for respiratory effort (respiratory movement signal) were validated against simultaneously measured gold standard signals. Compared with the gold standard, we validated 1) tidal volume (correlation, R 2 = 0.87, P < 0.001; and agreement within 1%, P < 0.001); 2) inspiratory airflow (correlation, R 2 = 0.92, P < 0.001; agreement within 4%, P < 0.001); 3) expiratory airflow (correlation, R 2 = 0.83, P < 0.001); and 4) respiratory movement signal (correlation, R 2 = 0.79-0.84, P < 0.001). The expiratory airflow signal, however, demonstrated a decrease in amplitude compared with the gold standard. Integrating respiratory and EEG/EMG signals, we fully characterized sleep and breathing patterns in conscious, unrestrained mice and demonstrated inspiratory flow limitation in a New Zealand Obese mouse. Our approach will facilitate studies of SRBD mechanisms in inbred mouse strains and offer a powerful platform to investigate the effects of environmental and pharmacological exposures on breathing disturbances during sleep and wakefulness.
KW - Airflow
KW - Inspiratory flow limitation
KW - Open system
KW - Polysomnography
KW - Respiratory effort signal
KW - Tidal volume
KW - Upper airway
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U2 - 10.1152/japplphysiol.00818.2011
DO - 10.1152/japplphysiol.00818.2011
M3 - Article
C2 - 22134700
AN - SCOPUS:84859611638
SN - 8750-7587
VL - 112
SP - 671
EP - 680
JO - Journal of applied physiology
JF - Journal of applied physiology
IS - 4
ER -