Effects of 17beta-estradiol on the baroreflex control of sympathetic activity in conscious ovariectomized rats
Autor: | Xiao-Rui He, Joan T. Crofton, Leonard Share, Weihua Wang |
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Rok vydání: | 1999 |
Předmět: |
Nitroprusside
Vasopressin medicine.medical_specialty Sympathetic nervous system Mean arterial pressure Cardiotonic Agents Sympathetic Nervous System Physiology Ovariectomy Blood Pressure Baroreflex Splanchnic nerves Rats Sprague-Dawley Phenylephrine Heart Rate Physiology (medical) Internal medicine medicine Animals Antihypertensive Agents Estradiol business.industry Splanchnic Nerves Rats Arginine Vasopressin Autonomic nervous system medicine.anatomical_structure Endocrinology Injections Intravenous cardiovascular system Ovariectomized rat Female business circulatory and respiratory physiology medicine.drug |
Zdroj: | The American journal of physiology. 277(2) |
ISSN: | 0002-9513 |
Popis: | The effects of chronic treatment with 17β-estradiol on baroreflex control of sympathetic activity were examined in conscious unrestrained ovariectomized rats. Baroreflex function was evaluated by logistic sigmoidal analysis of the relationships between changes in mean arterial pressure (MABP) and changes in heart rate (HR) and splanchnic nerve activity (SNA) when MABP was rapidly increased to 150 mmHg by intravenous phenylephrine after its reduction to 50 mmHg by intravenous nitroprusside. These baroreflex function curves were similar in vehicle- and estradiol-treated rats. However, after a 30-min infusion of vasopressin in vehicle-treated rats, the curve for HR was shifted downward, and the upper plateau and maximum gain for the SNA curve were reduced. These effects were abolished by estradiol. A 30-min phenylephrine infusion had no effect on the baroreflex curves. Thus estrogen can modulate the action of vasopressin on baroreflex control of sympathetic outflow and thereby participate in cardiovascular regulation. |
Databáze: | OpenAIRE |
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