Mammalian heart

Lee, K.S., Marban, E. and Tsien, R.W. (1985). Inactivation of calcium channels in mammalian heart cells joint dependence on membrane potential and intracellular calcium. J. Physiol. 364, 395-411. 

Blinks, J. R., Olson, C. B., Jewell, B. R., and Braveny, P., Influence of caffeine and other methyxanthines on mechanical properties of isolated mammalian heart muscle, Circ Research, 30, 367, 1972. 

Drury, A. N. Szent-Gyorgyi, A. (1929). The physiological activity of adenine compounds with special reference to their action upon mammalian heart. 

Inhalation of certain hydrocarbons, including some anesthetics, can make the mammalian heart abnormally sensitive to epinephrine, resulting in ventricular arrhythmias, which in some cases can lead to sudden death (Reinhardt et al. 1971). The mechanism of action of cardiac sensitization is not completely understood but appears to involve a disturbance in the normal conduction of the electrical impulse through the heart, probably by producing a local disturbance in the electrical potential across cell membranes. The hydrocarbons themselves do not produce arrhythmia the arrhythmia is the result of the potentiation of endogenous epinephrine (adrenalin) by the hydrocarbon. 

Report 957-77, E.I. du Pont de Nemours and Co., Newark, DE. Test species/Strain/Sex/Number male beagle dogs (1-2 per exposure group) Exposure route/Concentrations/Durations Inhalation 2,600, 5,200, 10,000, and 21,600 ppm for 10 min (the cardiac sensitization test is a 10-min test) epinephrine dose at 8 g/kg. The cardiac sensitization test is based on the observation that some halocarbons make the mammalian heart abnormally sensitive to epinephrine, resulting in ectopic beats and/or ventricular fibrillation, which may result in death. 

An isolated mammalian heart whose extrinsic nervous connections have been severed will beat spontaneously for hours if it is supplied with a nutrient medium via the aortic trunk and coronary arteries (Langendorff preparation). In such a preparation, only those drugs that act directly on cardio-myocytes will alter contractile force and beating rate. 

T. Godfraind, A. de Pover, G. Castaneda Hernandez, M. Eagoo (1982). Cardiodigin endogenous digitalis-like material from mammalian heart. Arch. Int. Pharmacodyn. 258 165-167. 

An interesting phenomenon is that some of the voltage-insensitive gap junctional channels are gated, i.e. the channels open and close rather than remain open all the time. The mechanisms underlying this gating behavior of voltage-insensitive channels found in avian and mammalian hearts and in septate axons of earthworms are still unknown [Brink, 1991]. 

Gros D, Jary-Guichard T, ten Velde I, de Maziere A, van Kempen MJA, Davoust J, Briand JP, Morman AFM, Jongsma HJ Restricted distribution of connexin 40, a gap junctional protein, in mammalian heart. Circ Res 1994 74 839-851. 

Wilde AAM, Escande D, Schumacher CA, Thuringer D, Mestre M, Fiolet JWT, Janse MJ Potassium accumulation in the globally ischemic mammalian heart. A role for the ATP-sensitive potassium channel. Circ Res 1990 67 835-843. 

A quantitatively important pathway of cysteine catabolism in animals is oxidation to cysteine sulfinate (Fig. 24-25, reaction z),450 a two-step hydroxyl-ation requiring 02, NADPH or NADH, and Fe2+. Cysteine sulfinic acid can be further oxidized to cyste-ic acid (cysteine sulfonate),454 which can be decarbox-ylated to taurine. The latter is a component of bile salts (Fig. 22-16) and is one of the most abundant free amino acids in human tissues 455-457 Its concentration is high in excitable tissues, and it may be a neurotransmitter (Chapter 30). Taurine may have a special function in retinal photoreceptor cells. It is an essential dietary amino acid for cats, who may die of heart failure in its absence,458 and under some conditions for humans.459 In many marine invertebrates, teleosts, and amphibians taurine serves as a regulator of osmotic pressure, its concentration decreasing in fresh water and increasing in salt water. A similar role has been suggested for taurine in mammalian hearts. A chronically low concentration of Na+ leads to increased taurine.460 Taurine can be reduced to isethionic acid... 

Cardiotonic activities were also exhibited by medigenin and medigenin acetate, which are genins isolated from Melodious monogynus (Apocyanaceae), when tested in isolated frog and mammalian hearts [245]... 

Drury AN, Szent-Gyorgyi A (1929) The physiological activity of adenine compounds with especial reference to their action upon the mammalian heart. J Physiol 68(3) 213—237 Englert M, Quitterer U, Klotz K-N (2002) Effector coupling of stably transfected human A3 adenosine receptors in CHO cells. Biochem Pharmacol 64(l) 69-73 Fossetta J, Jackson J, Deno G, Fan X, Du XK, Bober L, Soude-Bermejo A, de Bouteiller O, Caux C, Lunn C, Lundell D, Palmer RK (2003) Pharmacological analysis of calcium responses mediated by the human A, adenosine receptor in monocyte-derived dendritic cells and recombinant cells. Mol Pharmacol 63(2) 342-350... 

Drury AN, Szent-Gyorgyi A (1929) The physiological activity of adenine compounds with especial reference to their action upon the mammalian heart. J Physiol 68(3) 213-237 Duncker DJ, Bache RJ (2008) Regulation of coronary blood flow during exercise. Physiol Rev 88(3) 1009-1086... 

Luo, W., Wolska, B.M., Grupp, I.L., etal., 1996, Phospholamban gene dosage effects in the mammalian heart. Circ Res, 78(5), pp839 17. 

Wang Z, Shi H, Wang H. Functional M3 muscarinic acetylcholine receptors in mammalian hearts. BrJ Pharmacol. 2004 142 395—108. 

Robinson, T.F., Cohen-Gould, L., and Factor, S.M. 1983. Skeletal framework of mammalian heart muscle. Arrangement of inter- and pericellular connective tissue structures. Lab. Invest. 49 482-498. 

The oxidation of long-chain fatty acids to acetyl-CoA is a central energy-yielding pathway in many organisms and tissues. In mammalian heart and liver, for example, it provides as much as 80% of the energetic needs under all physiological conditions (Lodish et al., 2003). 

Balaban, R.S., Kantor, H.L., Katz L.A., Briggs, R.W. (1986). Relation between work and phosphate metabolite in the in vivo paced mammalian heart Science 232,1121-1123. 

The biosynthesis of the adenine nucleotide carrier has been studied most extensively in Neurospora crassa. The carrier isolated from Neurospora mitochondria is very similar to the carrier isolated from mammalian mitochondria [78]. Its molecular weight, subunit structure, amino acid composition, hydrophobicity and inhibitor specificity are remarkably similar to the mammalian heart and liver carriers. Specific antibodies to the Neurospora carrier have been raised in rabbits [79]. 

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