Afterload-induced homeometric autoregulation in isolated cardiac muscle
| Autor: | TC Donald, DM Peterson, LL Hefner, AA Walker |
|---|---|
| Rok vydání: | 1976 |
| Předmět: |
medicine.medical_specialty
chemistry.chemical_element Beat (acoustics) Stimulation Isometric exercise In Vitro Techniques Calcium Biology Dogs Afterload Physiology (medical) Internal medicine Pressure medicine Animals Homeostasis Autoregulation Temperature Cardiac muscle Myocardial Contraction Electric Stimulation medicine.anatomical_structure chemistry Ventricle Anesthesia Cardiology |
| Zdroj: | American Journal of Physiology-Legacy Content. 231:545-550 |
| ISSN: | 0002-9513 |
| Popis: | Pressure-induced homeometric autoregulation (HAR) has been demonstrated by many investigators in the mammalian ventricle; In isolated cardiac muscle, however, several investigators have reported the opposite effect (anti-HAR); namely, that the first beat after a transition from isotonic to isometric contraction is the most forceful, with a decline over several beats to a steady state. In the present study we find that trabeculae from the canine right ventricle demonstrate either HAR or anti-HAR, depending on the rate of stimulation, the calcium level, and the temperature. Higher calcium, higher temperature, and lower rate of stimulation produce either less HAR or more anti-HAR. When only temperature and rate of stimulation are varied, in each muscle there is a unique rate for each temperature above which HAR occurs and below which anti-HAR occurs. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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