Biomaterial Database

Activation of the Langendorff perfused rat heart under depolarizing conditions. 1990

P F Abaurre, and I Stefanon, and J D Trindade, and C M Leite, and D V Vassallo

Departamento de Ciências Fisiológicas, Universidade Federal do Espírito Santo, Brasil.

Myocardial activation under depolarized conditions was studied in spontaneously beating Langendorff perfused hearts from albino rats. Depolarization was obtained increasing external potassium concentration in steps (5.4, 7.4, 10, 10.5, 11, 11.5 mM) in the perfusing solution. Left ventricular isovolumic systolic pressure and coronary flow did not change as external potassium increased, but the atrial and ventricular beat rates decreased, the latter showing a larger decline. In the electrocardiogram, the P-R interval increased as a function of external potassium and the amplitude of the QRS complex diminished as its duration increased. The majority of perfused hearts stopped pumping when external potassium was raised to 11.5 mM.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009200	Myocardial Contraction	Contractile activity of the MYOCARDIUM.	Heart Contractility,Inotropism, Cardiac,Cardiac Inotropism,Cardiac Inotropisms,Contractilities, Heart,Contractility, Heart,Contraction, Myocardial,Contractions, Myocardial,Heart Contractilities,Inotropisms, Cardiac,Myocardial Contractions
D009206	Myocardium	The muscle tissue of the HEART. It is composed of striated, involuntary muscle cells (MYOCYTES, CARDIAC) connected to form the contractile pump to generate blood flow.	Muscle, Cardiac,Muscle, Heart,Cardiac Muscle,Myocardia,Cardiac Muscles,Heart Muscle,Heart Muscles,Muscles, Cardiac,Muscles, Heart
D010477	Perfusion	Treatment process involving the injection of fluid into an organ or tissue.	Perfusions
D011188	Potassium	An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
D003326	Coronary Circulation	The circulation of blood through the CORONARY VESSELS of the HEART.	Circulation, Coronary
D004594	Electrophysiology	The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
D005260	Female		Females
D000200	Action Potentials	Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli.	Spike Potentials,Nerve Impulses,Action Potential,Impulse, Nerve,Impulses, Nerve,Nerve Impulse,Potential, Action,Potential, Spike,Potentials, Action,Potentials, Spike,Spike Potential
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia