Pressor effect of endothelium-derived relaxing factor inhibition in conscious virgin and gravid rats
| Autor: | Marshall D. Lindheimer, William M. Barron, J. G. Umans |
|---|---|
| Rok vydání: | 1990 |
| Předmět: |
medicine.medical_specialty
Mean arterial pressure Physiology Hemodynamics Blood Pressure Vasodilation Arginine Nitric Oxide Phenylephrine chemistry.chemical_compound Heart Rate Pregnancy Internal medicine Heart rate medicine Animals reproductive and urinary physiology Sexual Abstinence omega-N-Methylarginine business.industry Endothelium-derived relaxing factor Rats Inbred Strains Rats Endocrinology Blood pressure chemistry Circulatory system cardiovascular system Pregnancy Animal Female business medicine.drug |
| Zdroj: | American Journal of Physiology-Renal Physiology. 259:F293-F296 |
| ISSN: | 1522-1466 1931-857X |
| DOI: | 10.1152/ajprenal.1990.259.2.f293 |
| Popis: | We used pressor responses to N-methylarginine (NMA), a specific inhibitor of endothelium-derived relaxing factor (EDRF) biosynthesis, to assess the contribution of EDRF to control of basal blood pressure in conscious, chronically instrumented virgin and gravid rats. Hypotheses were that NMA would raise blood pressure in conscious animals in spite of intact cardiovascular reflexes and that differing effects in virgin and pregnant animals would reveal contributions of EDRF to the physiological vasodilation of pregnancy. Basal mean arterial pressure (MAP) and heart rate (HR) were 106 +/- 12 mmHg and 394 +/- 27 beats/min (n = 31) in virgin and 102 +/- 8 mmHg and 378 +/- 18 beats/min (n = 14) in gravid rats. After NMA (150 mg/kg iv), increments in MAP and decreases in HR were similar in each group (virgin, delta MAP = 38 +/- 12 mmHg, delta HR = -65 +/- 27 beats/min, n = 14; gravid, delta MAP = 33 +/- 8 mmHg, delta HR = -63 +/- 20 beats/min, n = 6). Pretreatment with excess L-arginine reduced pressor responses to NMA by 80% in both pregnant and virgin animals. In contrast, L-arginine had no significant effect on the pressor response to phenylephrine (6.4 mg/kg iv). EDRF contributes importantly to regulation of basal blood pressure in conscious animals, and pregnancy does not alter the pressor effect of EDRF inhibition in the rat. |
| Databáze: | OpenAIRE |
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