N omega-amino-L-arginine, an inhibitor of nitric oxide synthase, raises vascular resistance but increases mortality rates in awake canines challenged with endotoxin
| Autor: | R F Lodato, Ronald J. Elin, W. D. Hoffman, J. P. Cobb, Jeanette M. Hosseini, Charles Natanson, C A Koev, Robert L. Danner, Sarah J. Banks, Michael A. Solomon |
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| Jazyk: | angličtina |
| Rok vydání: | 1992 |
| Předmět: |
medicine.medical_specialty
Mean arterial pressure Pulmonary Circulation Time Factors Arginine Immunology Biology Sepsis Dogs Oxygen Consumption Heart Rate Internal medicine Heart rate medicine Immunology and Allergy Animals Analysis of Variance Septic shock Heart Articles medicine.disease Shock Septic Nitric oxide synthase Endotoxins medicine.anatomical_structure Endocrinology Enzyme inhibitor Anesthesia Vascular resistance biology.protein Vascular Resistance Amino Acid Oxidoreductases Nitric Oxide Synthase |
| Zdroj: | The Journal of Experimental Medicine |
| ISSN: | 1540-9538 0022-1007 |
| Popis: | Inhibitors of nitric oxide synthase (NOS) have been reported to increase mean arterial pressure in animal models of sepsis and recently have been given to patients in septic shock. However, controlled studies to determine the effects of these agents on cardiovascular function and survival in awake animal models of sepsis have not been reported. To examine the therapeutic potential of NOS inhibition in septic shock, we challenged canines with endotoxin (2 or 4 mg/kg i.v.) and treated them with either normal saline or N omega-amino-L-arginine (10 or 1 mg/kg/h), the most specific inhibitor available for the isoform of NOS implicated in septic shock. Endotoxemic animals treated with N omega-amino-L-arginine (n = 11) had higher systemic and pulmonary vascular resistance indices (SVRI and PVRI, p less than or equal to 0.033) and decreased heart rates (p = 0.009), cardiac indices (CI, p = 0.01), oxygen delivery indices (p = 0.027), and oxygen consumption indices (p = 0.046) compared with controls (n = 6). Moreover, N omega-amino-L-arginine increased mortality rates after endotoxin challenge (10 of 11 vs. 1 of 6 controls, p = 0.005). Administration of L-arginine did not improve survival or alter the cardiopulmonary effects of N omega-amino-L-arginine, which suggests that inhibition of NOS may not have been competitive. In normal animals, N omega-amino-L-arginine alone (n = 3) increased SVRI (p = 0.0008) and mean arterial pressure (p = 0.016), and decreased CI (p = 0.01) compared with saline-treated controls (n = 3), but, at the high dose, also produced neuromuscular rigidity and seizure-like activity that was not apparent in the endotoxemic model. Thus, the mortality rate from endotoxemia increased either because of NOS inhibition per se or because of properties unique to N omega-amino-L-arginine, or both. |
| Databáze: | OpenAIRE |
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