Heart extraction

Juengling and Kammermeier (J2) reported the separation of purine nucleotides from rat heart extract using tetra-/t-butylammonium phosphate on a C-18 column. Although the chromatographic separation has poor resolution, they emphasize the need for a chromatographic technique for the simultaneous analysis of ionic and nonionic compounds that retains the flexibility of the reversed-phase mode. 

The major determinants of cardiac oxygen consumption are heart rate, myocardial wall tension (directly related to ventricular cavity pressure and volume) and force and velocity of contraction. Under normal conditions, the heart extracts oxygen at a near-maximal rate and added requirements are met by a reduction in coronary vascular resistance and an increase in blood flow. In the atherosclerotic heart, coronary vessels in the ischemic region and particularly in the subendocarium are already dilated and their ability to increase flow by further dilatation is severely compromised. Thus, under these conditions, increasing oxygen demand may exceed supply, myocardial ischemia ensues and the patient manifests symptoms of angina pectoris. 2... 

Oshima, N. Kotaki, H. Sawada, Y. Iga, T. Tissue distribution of amitriptyline after repeated administration in rats. Drug Metab.Dispos., 1994,22, 21-25 [rat plasma liver kidney lung brain muscle heart extracted nortriptyline clomipramine is IS column temp 35 LOQ 10 n mL pharmacokinetics]... 

Frenkel, R. 1968. Control of reduced diphosphopyridine nucleotide oscillations in beef heart extracts. I. Effect of modifiers of phosphofructokinase activity. Arch. Biochem. Biophys. 125 151-6. 

It is clear from this data that sometimes it is difficult to interpret the data from the Western—for an example, Insulin Receptor Substrate 1 (IRS-1) was detected in higher abundance in liver however, the Western did not reveal any protein bands at 180 kDa, and on overall, one could consider the total signal generated in the lane that was loaded with the heart extract to be higher than in the liver band (denoted with H for heart and L for liver). The opposite is true for the TF... 

Collagen amino acids Colostrum Colostrum cream Connective tissue extract Creatinine Crystalline Cyanocobalamin Cytochrome C Dextran sulfate sodium DNA Eicosapentaenoic acid Elastin Embryo extract Fibronectin Folic acid Guarana (Paullinia cupana) gum Heart extract Hematin Hemolymph extract Heparin Heparin sodium Hirudinea extract Honey Honey extract Hydrolyzed actin Hydrolyzed conchiorin protein Hydrolyzed DNA... 

Glycolytic oscillations are the best-known examples of metabolic oscillations. Glycolysis occurs in yeast cells, cell-free extracts, beef-heart extracts, rat skeletal-muscle extracts and tumour cells. Several reviews on the subject have appeared in the literature [18-22]. 

Inactive matter is successively removed with lead acetate, mercuric acetate and silver nitrate in weakly acid solution. The active fraction is then precipitated with silver in alkaline medium, treated with H,S and concentrated tn vaeuo 0.001 ml. of the concentrate is equivalent in activity to 1 mL of boiled heart extract (Fig. 1). 

Cardiolipin may function as a hapten and is the active principle of beef heart extracts in the complement fixation reaction with serum from syphilitic patients. 

Ochoa, S. (1943) EfiSciency of aerobic phosphorylation in cell-free heart extracts. J. Biol. Chem. 151, 498. 

Propionyl CoA incubated with pig heart extracts in the presence of ATP and Mg++ takes up C 0 and forms C -methylmalonyl CoA. A mixture of propionate and CoA will also react but is less effective than the CoA ester. Under optimal conditions of synthesis and with fractionated enzyme preparations, no succinate is formed. 

Homogenates of rat liver and pig heart, extracted in the cold with ethanol and then dialyzed against KCl-phosphate buffer, pH 7.4, containing 0.001 M L-cysteine served as the enzyme sources. 

Studies with yeast, heart, and brain have shown that concentrations of intermediates within the glycolytic pathway often follow an oscillating function. Continuous spectrophotometric recording techniques for determining the NAD" /NADH ratio in cell-free extracts first revealed oscillations of the NADH level in these systems. These studies then led to the discovery of glycolytic oscillations in yeast cell and cell-free extracts, beef heart extracts, rat skeletal muscle extracts, and in ascites tumor cells, with concentrations of intermediates varying in the range between 10 and 10 M (Chance et al., 1973). 

Loewi and Navratil have shown that ACh can be enzymatically inactivated by heart extracts (69). This, however, is not surprising, since, as pointed out by Stedman, Stedman, and Easson (127), esterases are widely distributed in the animal organism and are known to hydrolyze a variety of esters. The important question was whether there is an enzyme which specifically hydrolyzes ACh. Stedman, Stedman, and Easson (l.c.) prepared from horse serum an enzyme which they considered to be an esterase specific for ACh and called it choline esterase. Later investigations do not support the assumption that the enzyme prepared by Stedman, et al. is really a specific choline esterase. There exists, however, an esterase which is specific for ACh. The specificity may be demonstrated by testing the action of an esterase on a number of substrates. In this way, a pattern may be obtained which makes it possible to distinguish the specific choline esterase from other esterases. The esterase in all nerve tissue is either exclusively or predominantly choline esterase. The enzyme is extremely stable. If kept at low temperature and at neutral pH, its activity remains unchanged for many months. The specificity of the enzyme as w eil as other properties will be discussed elsewhere (Nachmansohn and Rothenberg, 131 Nachmansohn, 102). 

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