Experimental myocardial ischemia produced in dogs by proximal left anterior descending coronary artery ligation is accompanied relatively rapid (1 h) increases the number of (-) [3H]dihydroalprenolol binding sites without changing their dissociation constants ischemic ventricular tissue. The changes, persist for at least 8 h and are marked decreases tissue region norepinephrine content. In contrast, same canine model 1 did not result a significant change [3H]quinuclidynl benzilate constants....

In the present study, we evaluated physiological responsiveness of increased numbers beta-adrenergic receptors in ischemic canine myocardium to vivo stimulation by (-)-isoproterenol and epinephrine. After 1 hour temporary proximal left anterior descending coronary artery occlusion during a 15-minute period reflow, dogs received (1)-isoproterenol intravenously at rate sufficient increase their heart rates 20--40 beats/min. Following infusion isoproterenol, myocardial tissue was obtained from...

ATP citrate lyase was purified by two different procedures from the livers of rats first starved and then fed with a fat-deficient high carbohydrate-glycerol diet. These enzyme preparations were judged homogeneous sedimentation equilibrium polyacrylamide gel electrophoresis. The molecular weight native around 4.4 X 10(5) as determined equilibrium. On sodium dodecyl sulfate electrophoresis usually showed single protein band an estimated 1.2 10(5). A similar value for subunit obtained...

Previous work from this laboratory (1) indicates that angiotensin II (AII) can affect release of several anterior pituitary hormones, both in vivo and vitro. To ascertain whether specific receptors mediate the effects AII on pituitary, binding as well kinetics [125I] to rat membranes were analyzed. Binding was rapid, reaching equilibrium within 4 min at 37 C. Specific approximately 90%. Increasing concentrations ligand resulted saturation binding, with attained = 2 nM. Scatchard analysis...

Abstract Citrate synthases from animal tissues were found to bind Sepharose-ATP. A pure preparation of citrate synthase was obtained a crude fraction rat heart by the specific elution enzyme Sepharose-ATP with dead end complex-forming substrates, oxalacetate and CoA. The proposed mechanisms synthase, steady state kinetics, examined in light pattern using combinations substrates substrate analogs.

This light microscopic autoradiographic study was performed to test the hypotheses that (a) density of beta adrenergic receptors (BAR) may differ in various components heart and (b) BAR certain exhibit a selective response pharmacologic pathological stimuli. Blocks canine left ventricle were frozen tissue sections cut incubated (-)[3H]dihydroalprenolol (DHA) label BAR. For total nonspecific binding, serial with without 10(-5) M (+/-)propranolol. Scintillation spectrometry demonstrated rapid...

In the present study, we tested hypotheses that 1) different species have myocardial adrenergic receptor numbers and 2) selected “slow-channel” calcium antagonists compete with alpha-adrenergic for binding to varying degrees in species. The data obtained study demonstrate there is a markedly decreased number of alpha 1-adrenergic increased beta-adrenergic receptors canine compared rabbit rat myocardium. differences exist without major affinity studied. There was no significant difference...

Oxidative phosphorylation of isolated canine myocardial mitochondria has been evaluated after exposure to different concentrations phosphate (5--50 mM), lactate ion in excess (5--40 mM, pH 7.4), calcium (50--270 nmol/mg protein), lactic acidosis (pH 6.3), and mitochondrial protein dilution (in vitro volume expansion) for 10 min 8 h. The influence addition, acidosis, expansion on function were studied the isolation medium (0.18 M KCl, 0.5% BSA (bovine serum albumin), with or without...

Vitamin B12 deficiency has been shown to result in an increase content and activity of the hepatic cytosolic enzymes fatty acid synthesis. The present study demonstrated that ATP citrate lyase, enzyme whose positively correlated with rates biosynthesis, also increased livers B12-deficient animals. Total specific synthase, is unaffected by a variety dietary hormonal changes, was found be B12-deprived state. By contrast, succinate-cytochrome c reductase, portion multicomponent complex...

To study the time course of left ventricular structural and functional responses to chronic aortic regurgitation, regurgitation was surgically induced in rabbits, Doppler echocardiography performed preoperatively serially postoperatively for up 2.5 yr. Twenty-five New Zealand White rabbits underwent surgical induction 13 control animals sham operation. Left endocardial epicardial surfaces were digitized from M-mode echocardiograms measure rates change cavity dimensions wall thicknesses...

A pilot study was carried out to compare the effect of ethacrynic acid and frusemide on glucose tolerance in ten elderly inpatients, who were suffering from hemiparesis. One subject had be withdrawn. None seriously ill, previously known diabetic, or taking a diuretic. The mean two base-line tests compared with those after 14 days one diuretic, further 11 without diuretic another period other values taken for comparison peak two-hour sugar levels. No evidence emerged that either drug...

We have further defined the binding characteristics of [3H]nitrendipine to myocardial microsomal membranes cats, dogs, rats, and rabbits canine coronary vasculature (1.5-3.0 mm OD), we studied nitrendipine's effect on contractile responses in isolated feline cardiac muscle arteries. is rapid, saturable, reversible all four species these tissues. Feline myocardium has a single site with dissociation constant (KD) 1.94 nM. Canine may two classes sites, high-affinity having KD 0.17 Nitrendipine...

Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – 30,