Reduced vascular responsiveness after a single bout of dynamic exercise in the conscious rabbit
| Autor: | M. G. Howard, S. E. DiCarlo |
|---|---|
| Rok vydání: | 1992 |
| Předmět: |
Agonist
medicine.medical_specialty Adenosine Physiology medicine.drug_class Physical Exertion Pulsatile flow Hemodynamics Pressoreceptors In Vitro Techniques Phenylephrine Physiology (medical) Internal medicine Reflex Heart rate medicine Animals Dose-Response Relationship Drug business.industry Purinergic receptor Isoproterenol Receptors Purinergic Hindlimb Receptors Adrenergic Endocrinology medicine.anatomical_structure Regional Blood Flow Circulatory system Blood Vessels Rabbits business medicine.drug Blood vessel |
| Zdroj: | Journal of Applied Physiology. 73:2662-2667 |
| ISSN: | 1522-1601 8750-7587 |
| DOI: | 10.1152/jappl.1992.73.6.2662 |
| Popis: | We measured agonist-induced changes in the iliac artery blood flow velocity (IFV) independent of baroreflex-mediated compensatory mechanisms in chronically instrumented New Zealand White rabbits (n = 8). Animals were instrumented with a Doppler flow probe around the right common iliac artery. A Teflon catheter was inserted into the right iliolumbar artery for local infusion of the vasoactive agonists. Another Teflon catheter was inserted in the left femoral artery for the measurement of pulsatile and mean arterial (MAP) blood pressures and heart rate (HR). The alpha-adrenergic receptor agonist phenylephrine (PE, 1.32–10.0 micrograms), the beta 1- and beta 2-adrenergic receptor agonist isoproterenol (IP, 0.022–0.11 micrograms), and the purinergic receptor agonist adenosine (AD, 10.0–100.0 micrograms) were injected into the functionally isolated hindlimb, and dose-response curves were generated. Changes in IFV were obtained without changes in MAP or HR. Exercise increased HR, MAP, and IFV (65.3 +/- 7.1 beats/min, 11.1 +/- 2.2 mmHg, and 2.2 +/- 0.3 kHz, respectively). The maximum responses to PE, AD, and IP were reduced 29.0 +/- 6.7, 50.7 +/- 8.5, and 61.0 +/- 8.1%, respectively, after exercise. In conclusion, exercise attenuated adrenergic and purinergic receptor-mediated vascular responses in the intact conscious rabbit. |
| Databáze: | OpenAIRE |
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