Category Archives: Myocardium

Effects of hypoxia on myoglobin and antioxidant enzymes in rat myocardium (part 10)

It is attractive to speculate that several possibilities other than the antioxidant defense system may be involved in the protective effects of intermittent hypoxia. One possibility is a change in the stress proteins that are expressed. During the course of … Continue reading

Effects of hypoxia on myoglobin and antioxidant enzymes in rat myocardium (part 9)

Recently, myoglobin has been implicated as a free radical generator that results in lipoperoxidation during ischemia-reperfusion injury of myocardium . The generation of free radicals is one damaging effect of hypoxia . Normally, oxygen free radicals are maintained at low … Continue reading

Effects of hypoxia on myoglobin and antioxidant enzymes in rat myocardium (part 8)

DISCUSSION Myoglobin acts as an intracellular oxygen reservoir and an oxygen shuttle in the myocardium of mammals . Myoglobin is needed to maintain oxygen uptake because of the low oxygen tension under conditions of hypoxia . Our previous studies observed … Continue reading

Effects of hypoxia on myoglobin and antioxidant enzymes in rat myocardium (part 7)

Effects of intermittent hypoxia on antioxidant enzymes and MDA of left and right myocardium: SOD and CAT activity and MDA content from various groups were determined. SOD and CAT are antioxidant enzymes that can scavenge free radicals. MDA is a … Continue reading

Effects of hypoxia on myoglobin and antioxidant enzymes in rat myocardium (part 6)

Effects of continuous and intermittent hypoxia on the myoglobin content of left and right myocardium: The concentration of myoglobin in both the left and right myocardium was significantly higher in the group that underwent continuous hypoxia (3500 m for four … Continue reading

Effects of hypoxia on myoglobin and antioxidant enzymes in rat myocardium (part 5)

RESULTS Effects of continuous hypoxia and intermittent hypoxia on body weight, and left and right ventricular weight: The starting and final body weights of rats subjected to normoxia and hypoxia are shown in Table 1. Neither continuous hypoxia (3500 m … Continue reading

Effects of hypoxia on myoglobin and antioxidant enzymes in rat myocardium (part 4)

Myocardial antioxidants and malondialdehyde determination: Rat hearts were removed after death as described above. Left and right ventricles (about 0.15 g) were homogenized in 10 volumes (1.5 mL) of normal saline. The homogenate was centrifuged at 20,000 g for 30 … Continue reading

Effects of hypoxia on myoglobin and antioxidant enzymes in rat myocardium (part 3)

Experimental design: Sprague-Dawley rats were grouped at random (six or eight rats/group). Rats subjected to continuous hypoxia were housed in a hypobaric chamber for four weeks with free access to food and water. They were maintained on a cycle of … Continue reading

Effects of hypoxia on myoglobin and antioxidant enzymes in rat myocardium (part 2)

  Stress and ischemia, and combinations thereof, are of paramount importance in the development of severe heart disease. Excessive stress reaction is involved in the pathogenesis of arrhythmias and ischemic heart disease . On the other hand, physical stress, such … Continue reading

Effects of hypoxia on myoglobin and antioxidant enzymes in rat myocardium (part 1)

Myocardium is sensitive to ischemia or hypoxia, partly because of its high concentration of oxidative enzymes and high demand for oxygen. Under normal conditions, as much as 60% to 80% of coronary blood oxygen is taken up by the myocardium, … Continue reading