Spontaneous contractions of isolated rat portal vein under temperature perturbations.
We studied nonlinear dynamics underlying spontaneous rhythmical contractions of isolated rat portal vein. The signals were acquired at four different temperatures important in isolated blood vessels preparations: 4, 22, 37 and 40 degrees C. To characterize the system's nonlinearity, we calculated th...
| Publicado en: | Medical & Biological Engineering & Computing Vol. 48; no. 9; pp. 887 - 895 |
|---|---|
| Autores principales: | , , , , , , , |
| Formato: | research Journal Article |
| Publicado: |
Springer Nature
Sep2010
|
| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=ccm&AN=104569302&site=ehost-live header: @attributes: shortDbName: ccm uiTerm: 104569302 longDbName: CINAHL Complete uiTag: AN controlInfo: bkinfo: dissinfo: jinfo: jid: 01400118 PO0 jtl: Medical & Biological Engineering & Computing issn: 01400118 maglogo: N pubinfo: dt: Sep2010 vid: 48 iid: 9 pid: 237 pub: Springer Nature place: New York, New York artinfo: ui: 104569302 NLM20556663 2010755595 10.1007/s11517-010-0643-9 NLM20556663 104569302 ppf: 887 ppct: 8 formats: fmt: @attributes: type: P tig: atl: Spontaneous contractions of isolated rat portal vein under temperature perturbations. aug: au: Vuksanovic V Gal V Platisa MM Gojkovic-Bukarica L Vuksanović, Vesna Gal, Vera Platisa, Mirjana M Gojković-Bukarica, Ljiljana affil: Institute of Biophysics, Faculty of Medicine, University of Belgrade, Belgrade, Serbia sug: subj: Portal Vein Physiology Vasoconstriction Physiology Animals Physics Muscle, Smooth Physiology Periodicity Rats Temperature ab: We studied nonlinear dynamics underlying spontaneous rhythmical contractions of isolated rat portal vein. The signals were acquired at four different temperatures important in isolated blood vessels preparations: 4, 22, 37 and 40 degrees C. To characterize the system's nonlinearity, we calculated the largest Lyapunov exponent, sample entropy and scaling exponents. Evidence for nonlinearity was provided by analysis of surrogate data generated from the phase-randomized Fourier transform of the original sequences. Positive values of the largest Lyapunov exponent were obtained for the time series recorded under applied conditions, indicating that the system preserves its chaotic deterministic nature even far from the physiological temperature range. Scaling exponents revealed three distinctive regions with different correlation properties. The calculated measures that characterize the time series obtained at 4 degrees C were significantly different from those derived from data obtained at higher temperatures. System's dynamics becomes more complex or less predictable as temperature approaches physiological value. The computation of the largest Lyapunov exponent, sample entropy and correlation measures gave an insight into the complex dynamics of the isolated blood vessels rhythmicity. We identified different modes of rhythmical contractions of isolated rat portal vein which could improve understanding of possible control mechanisms in vivo. pubtype: Academic Journal doctype: research Journal Article ougenre: Article language: English refInfo: holdings: @attributes: islocal: N |
|---|