Monotone Signal Segments Analysis as a novel method of breath detection and breath-to-breath interval analysis in rat.
We applied a novel approach to respiratory waveform analysis--Monotone Signal Segments Analysis (MSSA) on 6-h recordings of respiratory signals in rats. To validate MSSA as a respiratory signal analysis tool we tested it by detecting: breaths and breath-to-breath intervals; respiratory timing and volume modes; and changes in respiratory pattern caused by lesions of monoaminergic systems in rats. MSSA differentiated three respiratory timing (tachypneic, eupneic, bradypneic-apneic), and three volume (artifacts, normovolemic, hypervolemic-sighs) modes. Lesion-induced respiratory pattern modulation was visible as shifts in the distributions of monotone signal segment amplitudes, and of breath-to-breath intervals. Specifically, noradrenergic lesion induced an increase in mean volume (p<or=0.03), with no change of the mean breath-to-breath interval duration (p>or=0.06). MSSA of timing modes detected noradrenergic lesion-induced interdependent changes in the balance of eupneic (decrease; p<or=0.02), and tachypneic (an increase; p<or=0.02) breath intervals with respect to control. In terms of breath durations within each timing mode, there was a tendency toward prolongation of the eupneic (p<or=0.08) and bradypneic-apneic (p<or=0.06) intervals. These results demonstrate that MSSA is sensitive to subtle shifts in respiratory rhythmogenesis not detectable by simple respiratory pattern descriptive statistics. MSSA represents a potentially valuable new tool for investigations of respiratory pattern control.
Bojic
Tijana
T
School of Medicine, University of Belgrade, 11000 Belgrade, Serbia.
Saponjic
Jasna
J
Radulovacki
Miodrag
M
Carley
David W
DW
Kalauzi
Aleksandar
A
D018663:Adrenergic Agents / Q000633:toxicity; D000818:Animals; D001596:Benzylamines / Q000633:toxicity; D008297:Male; D017286:Polysomnography / Q000379:methods; D051381:Rats; D017207:Rats, Sprague-Dawley; D012016:Reference Values; D012129:Respiratory Function Tests / Q000379:methods*; D015656:Respiratory Mechanics / Q000187:drug effects / Q000502:physiology*; D013990:Tidal Volume / Q000187:drug effects / Q000502:physiology; D013997:Time Factors
D018663:Adrenergic Agents; D001596:Benzylamines; C012102:DSP 4