Comparison of digoxin with some digitoxin metabolites on cat heart lung preparation

The effect of calcium on heart rate, A-V conduction, and contractility was studied in the dog's heart-lung preparation. Normal plasma calcium concentration was 2.71 ± 0.20 mm (N = 25). Heart rate was increased by calcium in the range from 1.6 to 14.0 mm and fell at still higher levels. A-V conduction time was shortest at calcium concentration slightly above normal, and decreased at higher as well as lower concentrations. At levels above 17 mm conduction block, fibrillation or cardiac arrest, or both, occurred. Contractile force was markedly reduced at low calcium. Increase of calcium lowered ventricular filling pressure, increased the rate of tension development and of relaxation, and shortened duration of contraction. The effects of calcium were not altered by pretreatment with reserpine (2 x 0.5 mg/kg, s.c., given 48 and 24 hr prior to experiment) and were not influenced by atropine (2–5 mg). The effect of calcium on contractility was fully developed 100 sec after administration; the effect on sinoatrial rhythm was established only after 4.4 ± 0.54 min.

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Effect of l-lysine on the cardiac function and metabolism in heart lung preparation M.Nagano, K.Takahashi, H.Maeno, A.Komori and T.Shikano. Department of Internal Medicine, Jikei Univ., School of Medicine. Tokyo

Journal of Molecular and Cellular Cardiology ◽

10.1016/0022-2828(83)90135-9 ◽

1983 ◽

Vol 15 ◽

pp. 33

Keyword(s):

Internal Medicine ◽

Cardiac Function ◽

School Of Medicine ◽

Lung Preparation

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The dynamics of the non-failure period of the isolated heart and heart-lung preparation

American Heart Journal ◽

10.1016/s0002-8703(45)90021-4 ◽

1945 ◽

Vol 30 (3) ◽

pp. 317-318

Keyword(s):

Isolated Heart ◽

Lung Preparation

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Neutrophils are Required for PMA-Induced Endothelial Ectoenzyme Dysfunction: Study in Perfused Lung Preparation

Vascular Endothelium ◽

10.1007/978-1-4615-3736-6_26 ◽

1991 ◽

pp. 245-245

Author(s):

Xilin Chen ◽

M. Tzanela ◽

J. R. McCormick ◽

J. D. Catravas

Keyword(s):

Perfused Lung ◽

Lung Preparation

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THE EFFECT OF ACETYLCHOLINE ON ADRENALINE-INDUCED SUBATRIAL RHYTHMS IN THE SENSITIZED CAT HEART

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y64-052 ◽

1964 ◽

Vol 42 (4) ◽

pp. 431-445 ◽

Cited By ~ 5

Author(s):

Don P. MacLeod ◽

A. K. Reynolds

Keyword(s):

Petroleum Ether ◽

Papillary Muscle ◽

Antiarrhythmic Agent ◽

Ventricular Automaticity ◽

Cat Heart

Acetylcholine has been shown to be an effective antiarrhythmic agent against arrhythmias induced by adrenaline in combination with the myocardial sensitizers petroleum ether, halothane, and harman methosulphate. It has also been shown that acetylcholine will reduce or prevent the increase in ventricular automaticity produced by adrenaline in the intact cat and in the isolated papillary muscle of the cat. All of these actions of acetylcholine can be blocked by atropine. Evidence from experiments in which petroleum ether inhalation was begun after an arrhythmia had been induced by adrenaline indicated that petroleum ether was causing an increase in ventricular automaticity. The results appear to support the idea that petroleum ether and possibly other sensitizers interfere with the stabilizing action of endogenous acetylcholine on the ventricle and allow the stimulating action of adrenaline to produce severe prefibrillatory rhythms by an increase in ventricular automaticity.

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