oxytetracycline--anhydrous and Myocardial-Infarction

Isoprenaline dosed 50 mg/kg was injected intraperitoneally into rats aged 42 days, 3 months, and 18 months. At intervals of 12, 18, 24, 48 hours and 5 days the degree of myocardial lesion was checked by the technetium-labeled oxytetracycline [99mTc-Sn-oxytetracycline] method. Three hours after its i. v. injection the myocardial radioactivity was measured in a control group and in the group treated with isoprenaline. Markedly higher radioactivity was found in animals given isoprenaline than in the controls. Besides, the degree of myocardial lesion considerably varied in dependence on the animals' age, being lowest in the 42-days-old and highest in the 18-months-old rats. In all age groups a biphasic alteration was observed, consisting of a phase of rapid decrease in radioactivity up to 24 hours, and a phase of slow decrease from the 24th hour till the 5th day after injection of isoprenaline. The authors consider the method using technetium-labeled oxytetracycline convenient for assessing the degree of myocardial lesion.

Topics: Age Factors; Animals; Isoproterenol; Myocardial Infarction; Oxytetracycline; Rats; Technetium

The single intramuscular injection of 275 mg Rolitetracyclin (Reverin) led to a rise in serum creatine phosphokinase in 11 out of 20 heart healthy patients, 7 cases with values over 100 mU/ml. In sane cases the initial values had still not been reached 72 hours after injection. With Rolitetracyclin given intravenously the creatine phosphokinase values do not alter, as with an isotonic Na-Cl solution given intramuscularly. A rise in the serum creatine phosphokinase was seen in 2 out of 6 cases after an intramuscular injection of Oxytetracyclin (Terramycin -Depot). One is not dealing with a reaction which is typical only to Rolitetracyclin. The cause is thought to be the setting free of enzymes through the musclelesions. The results underline the sensitivity of and problems involved with creatine phosphokinase in the diagnosis of heart-infarction.

Topics: Adult; Aspartate Aminotransferases; Creatine Kinase; Diagnostic Errors; False Positive Reactions; Female; Humans; L-Lactate Dehydrogenase; Male; Middle Aged; Myocardial Infarction; Oxytetracycline; Rolitetracycline; Sodium Chloride; Tetracycline; Time Factors

The suitability of various radiopharmaceuticals (99mTc-tetracycline analogs, 99mTc-glucoheptonate, 99mTc-diphosphonate, and 67Ga-citrate) for use in imaging acute myocardial infarction was assessed by determining their biologic distributions in experimentally infarcted dogs. The highest infarct-to-normal myocardial concentration ratio was found with 99mTc-diphosphonate (27.9:1); the highest infarct-to-liver ratio was also found with 99mTc-diphosphonate (15.9:1). The infarct-to-bone ratio, however, was 0.4:1 with 99mTc-diphosphonate. There was an excellent positive linear correlation between blood-flow reduction and uptake of the radiopharmaceutical after a threshold reduction in blood flow with 99mTc-glucoheptonate and 99mTc-tetracycline. Technetium-99m-tetracycline accumulated only in infarcted tissue while 99mTc-diphosphonate was increased in both ischemic and infarcted tissue. Thus, 99mTc-diphosphonate has characteristics best suited for scintigraphic imaging. Since 99mTc-tetracycline accumulates only in infarcted tissue, however, this tracer more accurately defines the size of an acute infarction.

Topics: Animals; Chlortetracycline; Dogs; Gallium Radioisotopes; Heptoses; Myocardial Infarction; Organophosphorus Compounds; Oxytetracycline; Radionuclide Imaging; Sugar Acids; Technetium; Tetracyclines

Topics: Anti-Bacterial Agents; Cardiovascular Diseases; Chlortetracycline; Fluorescence; Myocardial Infarction; Oxytetracycline; Protein Synthesis Inhibitors; Tetracycline