STUDY OBJECTIVES To evaluate measurements of myoglobin in the diagnosis of perioperative myocardial tissue damage in aortocoronary bypass surgery. A new immunoturbidimetric myoglobin assay, which yields quantitative concentrations of myoglobin within approximately 1 min, was used. DESIGN Prospective clinical study. PATIENTS Thirty-two patients scheduled for elective aortocoronary bypass sur...

BACKGROUND Hypoxic vasodilation is a physiological response to low oxygen tension that increases blood supply to match metabolic demands. Although this response has been characterized for >100 years, the underlying hypoxic sensing and effector signaling mechanisms remain uncertain. We have shown that deoxygenated myoglobin in the heart can reduce nitrite to nitric oxide (NO·) and thereby contri...

Rates and mechanisms of myoglobin removal from plasma were examined in closed-chest dogs, using disappearance patterns of immunoreactivity and radioactivity after i.v. canine myoglobin radiolabeled with 125I. Arterial immunoreactive myoglobin concentration decreased monoexponentially over a 2-decade range, with rate constants of disappearance averaging -0.080 +/- 0.014 min-1 (+/- SD) (correspon...

THE ROLE OF MYOGLOBIN as an oxygen storage protein in the muscles of diving birds and mammals is well-established (8). In contrast, the function of the lower myoglobin content in striated muscles of humans and other terrestrial vertebrates has long been a subject of debate. In a seminal review published in 1939, Millikan (13) identified three potential functional roles for myoglobin in the aero...

The objective was to compare oxygenation and reduction potential properties of bovine and porcine myoglobins in-vitro. Cyclic voltammetry and homology-based myoglobin modeling were used to determine the species-specific effects on myoglobin reduction potential and oxygenation properties at pH 5.6, 6.4, and 7.4. At all pHs, porcine myoglobin had greater (P = 0.04) oxygen affinity than bovine myo...

Myoglobin-mediated oxygen delivery to intracellular mitochondria is demonstrated in cardiac myocytes isolated from the hearts of mature rats. Myocytes are held at high ambient oxygen pressure, 40-340 torr (5-45 kPa); sarcoplasmic myoglobin is fully oxygenated. In this condition oxygen availability does not limit respiratory rate; myoglobin-facilitated diffusion contributes no additional oxygen ...

Myoglobin acts as an oxygen store and a reactive oxygen species acceptor in muscles. We examined myoglobin mRNA in rat cardiac ventricle and skeletal muscles during the first 42 days of life and the impact of transient neonatal hypo- and hyperthyroidism on the myoglobin gene expression pattern. Cardiac ventricle and skeletal muscles of Wistar rats at 7-42 days of life were quickly removed, and ...

Intracellular iron reportedly mediates many forms of tissue injury, including ischemic and myohemoglobinuric acute renal failure. This action may be explained by the ability of iron to catalyze the formation of the highly toxic hydroxyl radical (.OH) from H202 via the Fenton/Haber-Weiss reactions. To assess whether renal tubular myoglobin/iron loading, induced by a physiological mechanism (endo...

purpose: myocardial infarction is among the most common diagnoses in patients admitted   to hospitals in western countries, and its rapid diagnosis is of utmost importance. this study   was conducted to determine the most sensitive double-marker cardiac isoenzyme of creatinine   kinase, troponin i, and myoglobin for diagnosing acute myocardial infarction.   materials and methods: this was an ob...

In 52 patients with myasthenia gravis serum myoglobin showed a significant inverse correlation to circulating thyroxine and triiodothyronine levels. The highest myoglobin concentration (240 ng/ml) was found in a myasthenia gravis patient with hypothyroidism. Slightly elevated myoglobin (54-60 ng/ml) was measured in four euthyroid myasthenic patients. The data suggest that a concomitant hypothyr...