... in the eastern Beaufort Sea. Muscle myoglobin concentrations averaged 77.9 mg g −1 , one of the highest values reported among mammals. Importantly, blood haematocrit, haemoglobin and muscle myoglobin concentrations correlated positively to indices of body condition, including maximum half-girth to length ratios...

...Shawn R. Noren; Kristi West ABSTRACT The length of time required for postnatal maturation of the locomotor muscle (longissimus dorsi) biochemistry [myoglobin (Mb) content and buffering capacity] in marine mammals typically varies with nursing duration, but it can be accelerated by species-specific...

... that facilitates performance over this altitudinal cline by comparing the respiratory capacities of permeabilized fibers, the activities of 16 key metabolic enzymes and the myoglobin content in muscles between high- and low-altitude populations of this species. Mitochondrial respiratory capacities (assessed using...

... are born with high myoglobin content (1.56±0.02 g 100 g −1 wet muscle mass, N =2) that matures rapidly. Myoglobin increased by 452% during the first year after birth and achieved adult levels (6.91±0.35 g 100 g −1 wet muscle mass, N =9) by 14 months postpartum. Buffering capacity was 48.88±0.69 slykes ( N...

... characterized age-specific dive limits of walruses by measuring anaerobic (acid-buffering capacity) and aerobic (myoglobin content) capacities of the muscles that power hind (longissimus dorsi) and fore (supraspinatus) flipper propulsion. Mean buffering capacities were similar across muscles and age classes...

...B. P. Velten; R. M. Dillaman; S. T. Kinsey; W. A. McLellan; D. A. Pabst SUMMARY Most marine mammals are hypothesized to routinely dive within their aerobic dive limit (ADL). Mammals that regularly perform deep, long-duration dives have locomotor muscles with elevated myoglobin concentrations...

...Michael A. De Miranda, Jr; Amber E. Schlater; Todd L. Green; Shane B. Kanatous SUMMARY A key cellular adaptation to diving in Weddell seals is enhanced myoglobin concentrations in their skeletal muscles, which serve to store oxygen to sustain a lipid-based aerobic metabolism. The aim of this study...

... ( pponganis@ucsd.edu ) 21 7 2011 © 2011. 2011 aerobic dive limit blood flow heart rate hemoglobin hypoxemia marine mammals metabolic rate myoglobin oxygen stores penguins re-perfusion injury seals In a landmark paper in diving physiology, Kooyman and co-workers...

...-infrared spectrophotometer was developed and used to measure myoglobin (Mb) O 2 saturation levels in the locomotory muscle during dives of emperor penguins ( Aptenodytes forsteri ). Two distinct patterns of muscle O 2 depletion were observed. Type A dives had a monotonic decline, and, in dives near the ADL...

...Ulrich Flögel; Angela Fago; Tienush Rassaf SUMMARY Myoglobin (Mb) is an important intracellular oxygen-binding hemoprotein found in the cytoplasm of skeletal and cardiac muscle tissue playing a well-known role in O 2 storage and delivery. Within the last decade the knowledge about Mb's function has...

...U. B. Hendgen-Cotta; U. Flögel; M. Kelm; T. Rassaf SUMMARY For more than 100 years, myoglobin has been among the most extensively studied proteins. Since the first comprehensive review on myoglobin function as a dioxygen store by Millikan in 1939 and the discovery of its structure 50 years ago...

...Shane B. Kanatous; Pradeep P. A. Mammen SUMMARY Myoglobin is a well-characterized, cytoplasmic hemoprotein that is expressed primarily in cardiomyocytes and oxidative skeletal muscle fibers. However, recent studies also suggest low-level myoglobin expression in various non-muscle tissues. Prior...

...P. J. Ponganis; T. J. Welch; L. S. Welch; T. K. Stockard SUMMARY Increased oxygen storage is essential to the diving capacities of marine mammals and seabirds. However, the molecular mechanisms underlying this adaptation are unknown. Myoglobin (Mb) and Mb mRNA concentrations were analyzed...

...Paul J. Ponganis; Ulrike Kreutzer; Torre K. Stockard; Ping-Chang Lin; Napapon Sailasuta; Tuan-Khan Tran; Ralph Hurd; Thomas Jue SUMMARY In order to examine myoglobin (Mb) function and metabolic responses of seal muscle during progressive ischemia and hypoxemia, Mb saturation and high-energy...

...Jonathan B. Wittenberg; Beatrice A. Wittenberg SUMMARY The heart, red skeletal muscles and the nitrogen-fixing legume root nodule function in steady states of high oxygen influx, partial oxygenation of cytoplasmic myoglobin or leghemoglobin and correspondingly low oxygen partial pressure. Here, we...

...T. J. Wright; R. W. Davis SUMMARY One physiological adaptation for prolonged dive duration in marine mammals is an elevated myoglobin (Mb) concentration in skeletal muscle. To determine the influence of Mb concentration on the aerobic dive limit (ADL), we modified a previously published model...

...Anja Roesner; Thomas Hankeln; Thorsten Burmester SUMMARY Unlike most mammals, many fish species live and survive in environments with low or changing levels of oxygen. Respiratory proteins like hemoglobin or myoglobin bind or store oxygen, thus enhancing its availability to the respiratory chain...

...Bruce D. Sidell; Kristin M. O'Brien SUMMARY The Antarctic icefishes (Family Channichthyidae) provide excellent examples of unique traits that can arise in a chronically cold and isolated environment. Their loss of hemoglobin (Hb) expression, and in some cases, loss of myoglobin (Mb) expression, has...

...George A. Ordway; Daniel J. Garry SUMMARY Myoglobin is a cytoplasmic hemoprotein, expressed solely in cardiac myocytes and oxidative skeletal muscle fibers, that reversibly binds O 2 by its heme residue, a porphyrin ring:iron ion complex. Since the initial discovery of its structure over 40 years...

... fiber diameter, high capillary density and greater myoglobin concentration) increasing O 2 flux from RM capillaries to the mitochondria. A study of the structural and biochemical features of the mako shark ( Isurus oxyrinchus ) RM was undertaken to enable performance-capacity comparisons of tuna...