Effect of an Increase in Heart Rate on the Pumping Function of the Heart Ventricles in Cold-Blooded Animals under Low Ambient Temperature Conditions
| Autor: | Dmitry Shmakov, V. P. Nuzhny, N. A. Kibler |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2020 |
| Předmět: |
medicine.medical_specialty
General Immunology and Microbiology Chemistry General Neuroscience lcsh:R temperature lcsh:Medicine Function (mathematics) rainbow trout General Biochemistry Genetics and Molecular Biology frog heart ventricle Internal medicine Heart rate medicine Cardiology cardiovascular system heart rate pumping function |
| Zdroj: | International Journal of Biomedicine, Vol 10, Iss 3, Pp 262-265 (2020) |
| ISSN: | 2158-0529 2158-0510 |
| Popis: | This study investigated the effect of heart rate (HR) on the pumping function of the heart ventricle (HV) in rainbow trout Oncorhynchus mykiss acclimated to a temperature of 5–7ºC, and in adult frogs Rana temporaria at an ambient temperature of 10–12ºC. The dynamics of intracavitary ventricular pressure was recorded by transmural catheterization. HR was changed by atrial electrocardiostimulation. The increase in HR in rainbow trout resulted in a decrease in the maximal systolic ventricular pressure (MSVP), an increase of end-diastolic ventricular pressure (EDVP), and a reduction in the maximum rates of the rising and falling pressures. In the frog, MSVP and isovolumic parameters (dP/dtmax and dP/dtmin) also decreased as HR increased from 24bpm to 42bpm. The preload of the frog's HV did not change significantly, compared to the sinoatrial rhythm (SR). The maximum increase in the frequency of atrial stimulation up to 60bpm in fish and up to 42bpm in frogs resulted in a significant decrease in the myocardial contractility and deterioration of the pumping function of HV under low ambient temperature conditions. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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