Distribution of amiodarone in heart tissues following intrapericardial administration.

The distribution of amiodarone (A) in heart tissues of open chest anesthetized animals was studied at 20 and 60 min following the insertion of an isotonic solution of the drug into the pericardial sac (PS) in doses from 0.25 to 3 mg per kg body weight (BW) for pigs and after 60 min in doses of 3 to 6 mg for dogs. Most of the A absorbed by the myocardium was found in the subepicardium part of the left ventricular (LV) wall.

The sarcolemmal Ca2+-ATPase of the ischemic-reperfused myocardium: protective effect of hypocalcemia on calmodulin-stimulated activity.

This study was designed to examine the role of calcium in the ischemia-induced changes of calmodulin-stimulated Ca2+-ATPase activity of heart sarcolemma of dogs subjected to coronary artery ligation (90 min) and reperfusion (30 min). This was attained by the application of systemic hemodialysis with low Ca2+ dialysate in six dogs (group A) and the comparison of the results with those obtained from animals subjected to normal Ca2+ hemodialysis (control group B, n=7). A very significant (p<0.

Apparent discontinuation rates in patients prescribed lipid-lowering drugs.

Objective: To evaluate apparent discontinuation rates in patients newly prescribed lipid-lowering drugs.

Design And Setting: A prospective survey of 12 months' dispensing data in 138 community pharmacies across metropolitan Sydney.

Patients: 610 adults (49% men) with a mean age of 58 years; 91% of prescriptions were from general practitioners; prescribed drugs were simvastatin (54%), pravastatin (31%) and gemfibrozil (15%).

Rapid diminution of calcium in the myocardium by transfer to pericardial solutions. Myocardial dialysis.

A new method is described for the controlled and specific depletion of calcium from the vascularly perfused heart of experimental animals by means of dialysis, using a pericardial solution. A 30-40 ml isotonic phosphate buffer pH 7.3 with a low Ca2+ and high Mg2+ concentration (0.

Distribution of lidocaine and digoxin in heart tissues and aorta following intrapericardial administration.

The distribution of lidocaine and digoxin in myocardial and aorta tissues of open chest anesthetized dogs was studied, following the administration of 30 ml phosphate buffer solution of the drugs in the pericardial cavity where it was kept for increasing time intervals. Transfer of lidocaine (15 or 30 mg) from the solution to myocardium was almost complete within 60 min, while only 50% of digoxin (2 or 50 micrograms) was removed, and this occurred during the first 30 min. Accordingly, the absorption rate of lidocaine by heart tissues increased with time up to 60 min while that of digoxin decreased with time.

Effect of low calcium on high-energy phosphates and sarcolemmal Na+/K(+)-ATPase in the infarcted-reperfused heart.

This study was undertaken to compare the effect of low to normal serum calcium on biochemical parameters in the myocardium of dogs subjected to 90 min of coronary artery ligation followed by 30 min reperfusion. The accumulation of calcium, the decrease of adenosine triphosphate (ATP) and creatine phosphate (CP) and the inhibition of sarcolemmal ouabain-sensitive Na+/K(+)-ATPase which are prominent findings in the ischemic-reperfused myocardium, were studied under normal and low serum Ca produced by normal and modified hemodialysis (HD). The results showed a lower accumulation of Ca (P less than 0.

Hemodialysis with calcium-free dialysate prevents myocardial creatine kinase depletion after brief coronary artery occlusion in dogs.

To evaluate the effect of hypocalcemia on myocardial creatine kinase (CK) depletion after brief coronary artery occlusion and reperfusion, dogs were rendered hypocalcemic via systemic hemodialysis for eighty minutes in the absence of Ca. Control animals were hemodialysed in the presence of Ca. The left anterior descending coronary artery was then occluded for six minutes and reperfusion for eighty minutes occurred at low flow of dialysate.

The correlation of serum amiodarone levels with abnormalities in the metabolism of thyroxine.

Amiodarone, a widely used iodine-containing antiarrhythmic drug, has been shown to divert the peripheral metabolism of T4 towards rT3 than T3. In this prospective study we correlated the concentration of the peripheral thyroid hormones in serum with that of amiodarone. Fifteen euthyroid volunteers were studied, 5 men and 10 women, with a mean age of 64.

Amiodarone--application and clinical pharmacology in atrial fibrillation and other arrhythmias.

Forty patients with atrial fibrillation (AF), 23 patients with ventricular extrasystoles (VES), and 11 patients with various arrhythmias (VA) were treated with amiodarone (0.2-0.6 g/day).

Effect of hypocalcemia on isoproterenol induced cardiotoxicity in dogs.

The effect of serum calcium on the myocardial damages produced by isoproterenol was studied in the dog. Hemodialysis for 80 min in the absence of calcium was used to alter serum calcium concentration in seven experimental animals. The same number of animals were dialysed in the presence of calcium and were used as controls.

Effect of heparin on myocardial contractility of the dog and on Na, K-ATPase.

It has recently been reported that heparin administration to rabbits is followed by an inhibition of the Na, K-ATPase of the myocardial sarcolemma. Further investigation of this phenomenon in an experimental animal which enables measurement of changes in myocardial contractility are presented here. The left ventricular pressure and the quotient of its first derivative to its total value (dp/dt/P) were followed for 60 min in 16 anesthetized dogs administered with heparin (700-5000 i.

Pharmacokinetics of amiodarone after intravenous and oral administration.

Pharmacokinetic studies were conducted in four subjects who received 150 mg amiodarone i.v., in nine subjects who received 200 or 400 mg amiodarone p.

Free fatty acids, central nervous system and bromazepam.

The concentrations of free fatty acids in plasma were estimated in thirty-three subjects, before and after (24 hours and 72 hours) the start of bromazepam oral administration in a daily dose of 6 mg (1.5 mg at 7 a.m.

Studies on glycosphingolipid biosynthesis by lectin-stimulated human lymphocytes.

1. Human peripheral lymphocytes, normal and stimulated by phytohemagglutinin or concanavalin A. were investigated with respect to their ability to biosynthesize neutral and acidic glycosphingolipids from D-[U-14C]glucose, D-[U-14C]galactose and D-[U-14C]glucosamine as precursors.

Isolation and partial characterization of the neutral glycosphingolipids and gangliosides of the human heart.

The glycosphingolipids (GSL) of the human heart muscle have been isolated from total lipids by column and thin layer chromatography and their sugars and fatty acids analyzed by gas liquid chromatography. Hearts from traffic victims were obtained at autopsy between 12 and 16 hr after death and dissected into parts (left and right ventricular walls, intraventricular septum and papillary muscle). The neutral GSL content for those parts of the hearts of two males aged 22 and one female aged 14 ranged from about 90 to 160 nmoles/g wet weight.

Changes in rat brain gangliosides following active avoidance conditioning.

Brain gangliosides of rats trained in a conditioned avoidance Sidman task and undisturbed rats in their cages were studied. The (14C) acetate was injected intracerebrally seven days before the starting of 30 days training. Thirty-seven days after injection all rats were killed and ganglioside fractions were isolated from neocortex, hippocampus, brain stem, cerebellum and residual cerebral tissue of each one brain.

Lipid composition of lymphocyte plasma membrane from pig mesenteric lymph node.

1. The lipid fraction of the plasma membrane of pig mesenteric lymph-node lymphocytes contained primarily (94%) neutral lipids and phospholipids in about equal weights. The remianing lipid comprised glycosphingolipids (1.

R-mediated beta-lactamases and episomal resistance to the beta-lactam drugs in different bacterial hosts.

Ten penicillinase plasmids of varying taxonomic origin were studied after transfer to a variety of bacterial hosts. Nine of the ten plasmids specified enzymes with the following identical, or very similar, properties: substrate profile, molecular weight, susceptibility to heat and inhibitors, and electrophoretic mobility, i.e.