Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1323099 (sympathomimetic)
 2,957 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Methylephedrine is a sympathomimetic amine that appears in many over-the-counter cough and cold medications throughout the world. The abuse of methylephedrine-containing medications has been reported in Japan. Although methylephedrine is not available in the United States, it was identified in 15 cases received by the Forensic Toxicology Laboratory, Division of Forensic Toxicology, Office of the Armed Forces Medical Examiner, Armed Forces Institute of Pathology over a two-year period; 12 of the 15 cases were collected from patients or decedents located within the confines of the continental United States. Methylephedrine was identified in each case by gas chromatography-nitrogen-phosphorus detection following an alkaline extraction and subsequently confirmed using full scan electron impact mass spectrometry. Quantitation of underivatized methylephedrine was performed using the same technique. Blood methylephedrine concentrations ranged from less than 0.05 to 0.28 mg/L (n = 14), and the mean methylephedrine concentration in urine was 1.6 mg/L (range, 0.15-6.8, n = 11 [excluding case 6]). A literature search revealed little information pertaining to the interpretation of methylephedrine concentrations in the blood. Six of the 15 cases presented here were positive for methylephedrine in the blood. Three of these cases were postmortem cases, and the other three cases were nonfatal aircraft mishaps. There is no evidence in any of these cases that methylephedrine was present at toxic concentrations; therefore, it appears from the cases reviewed in this study that blood methylephedrine concentrations less than 0.3 mg/L are not associated with significant toxicity.
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PMID:Methylephedrine concentrations in blood and urine specimens. 968 34

In 16 dog heart-lung preparations modified to permit a more accurate measurement of coronary flow, adrenaline or noradrenaline was infused at a rate of 4 mug. base/min. After a 30-min. pause during which the increased oxygen consumption and heart rate, but not the coronary flow, returned to pre-infusion levels, the other sympathomimetic amine was infused for the same length of time. It was found that, mole per mole, noradrenaline is as effective, and probably more so, than adrenaline in raising the oxygen consumption of the heart-lung preparation. The positive chronotropic and coronary dilating action of both amines appear to be equal. It was observed that in any one experiment the second dose of the sympathomimetic amine was slightly more effective than the first dose in raising the oxygen consumption. The level of high-energy phosphorus compounds does not change after adrenaline or noradrenaline administration even at the time when the oxygen consumption rises to as much as 200%. During this period there are no signs of cardiac hypoxia, as can be judged by the good oxygen saturation of coronary venous blood. Single doses of 5 mug. adrenaline or noradrenaline have a consistent positive inotropic effect that lasts about 15 min. when tested on a failing heart. In 12 experiments on non-failing modified heart-lung preparations, a single dose of 5 mug. adrenaline fails to cause a measurable increase in oxygen consumption after 1, 3, 6, or 11 min. in spite of a mild positive chronotropic action. The significance of these findings is discussed and the suggestion made that, when noradrenaline infusions are effective in treating cardiogenic shock in man, part of this effect may be due to its positive inotropic action, thus correcting an element of heart failure that might exist.
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PMID:The effect of adrenaline and noradrenaline on the metabolism and performance of the isolated dog heart. 1369 21