title: Functional Assessment of Cardiac Responses of Adult Zebrafish (Danio rerio) to Acute and Chronic Temperature Change Using High-Resolution Echocardiography.
abstract: The zebrafish (Danio rerio) is an important organism as a model for understanding vertebrate cardiovascular development. However, little is known about adult ZF cardiac function and how contractile function changes to cope with fluctuations in ambient temperature. The goals of this study were to: 1) determine if high resolution echocardiography (HRE) in the presence of reduced cardiodepressant anesthetics could be used to accurately investigate the structural and functional properties of the ZF heart and 2) if the effect of ambient temperature changes both acutely and chronically could be determined non-invasively using HRE in vivo. Heart rate (HR) appears to be the critical factor in modifying cardiac output (CO) with ambient temperature fluctuation as it increases from 78 ± 5.9 bpm at 18°C to 162 ± 9.7 bpm at 28°C regardless of acclimation state (cold acclimated CA- 18°C; warm acclimated WA- 28°C). Stroke volume (SV) is highest when the ambient temperature matches the acclimation temperature, though this difference did not constitute a significant effect (CA 1.17 ± 0.15 μL at 18°C vs 1.06 ± 0.14 μl at 28°C; WA 1.10 ± 0.13 μL at 18°C vs 1.12 ± 0.12 μl at 28°C). The isovolumetric contraction time (IVCT) was significantly shorter in CA fish at 18°C. The CA group showed improved systolic function at 18°C in comparison to the WA group with significant increases in both ejection fraction and fractional shortening and decreases in IVCT. The decreased early peak (E) velocity and early peak velocity / atrial peak velocity (E/A) ratio in the CA group are likely associated with increased reliance on atrial contraction for ventricular filling.
authors.affiliation: Molecular Cardiac Physiology Group, Department of Biomedical Physiology and Kinesiology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.|Child and Family Research Institute, Department of Cardiovascular Science, 950 West 28th Ave, Vancouver, BC V5Z 4H4, Canada.
authors.forename: Ling
authors.initials: L
authors.lastname: Lee
authors.affiliation: Child and Family Research Institute, Department of Cardiovascular Science, 950 West 28th Ave, Vancouver, BC V5Z 4H4, Canada.
authors.forename: Christine E
authors.initials: CE
authors.lastname: Genge
authors.affiliation: School of Engineering Science, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.
authors.forename: Michelle
authors.initials: M
authors.lastname: Cua
authors.affiliation: Molecular Cardiac Physiology Group, Department of Biomedical Physiology and Kinesiology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.|Child and Family Research Institute, Department of Cardiovascular Science, 950 West 28th Ave, Vancouver, BC V5Z 4H4, Canada.
authors.forename: Xiaoye
authors.initials: X
authors.lastname: Sheng
authors.affiliation: Molecular Cardiac Physiology Group, Department of Biomedical Physiology and Kinesiology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.
authors.forename: Kaveh
authors.initials: K
authors.lastname: Rayani
authors.affiliation: School of Engineering Science, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.
authors.forename: Mirza F
authors.initials: MF
authors.lastname: Beg
authors.affiliation: School of Engineering Science, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.
authors.forename: Marinko V
authors.initials: MV
authors.lastname: Sarunic
authors.affiliation: Molecular Cardiac Physiology Group, Department of Biomedical Physiology and Kinesiology, Simon Fraser University, 8888 University Drive, Burnaby, BC V5A 1S6, Canada.|Child and Family Research Institute, Department of Cardiovascular Science, 950 West 28th Ave, Vancouver, BC V5Z 4H4, Canada.
authors.forename: Glen F
authors.initials: GF
authors.lastname: Tibbits
mesh_terms: D000064:Acclimatization / Q000502:physiology*; D062365:Aminobenzoates / Q000494:pharmacology; D000704:Analysis of Variance; D000777:Anesthetics / Q000494:pharmacology; D000818:Animals; D002302:Cardiac Output / Q000187:drug effects / Q000502:physiology; D004452:Echocardiography / Q000379:methods*; D006321:Heart / Q000187:drug effects / Q000502:physiology*; D006339:Heart Rate / Q000187:drug effects / Q000502:physiology; D007530:Isoflurane / Q000494:pharmacology; D009200:Myocardial Contraction / Q000187:drug effects / Q000502:physiology; D013318:Stroke Volume / Q000187:drug effects / Q000502:physiology; D013696:Temperature; D015027:Zebrafish / Q000502:physiology*
chemical_list: D062365:Aminobenzoates; D000777:Anesthetics; C003636:tricaine; D007530:Isoflurane