Biomaterial Database

Electrophysiological and functional effects of adenosine on ventricular myocytes of various mammalian species. 1996

Y Song, and L Belardinelli

Department of Medicine, University of Florida Medical School, Gainesville 32610, USA.

The goal of this study was to determine the electrophysiological and functional effects of adenosine on ventricular myocytes of guinea pig, rabbit, rat, and ferret hearts. Adenosine (100 microM) shortened the action potential durations of rat and ferret myocytes by 14 +/- 1 and 57 +/- 7%, reduced the amplitudes of cell twitch shortening by 13 +/- 1 and 54 +/- 5%, and increased outward currents by 15 +/- 4 and 55 +/- 5%, respectively, but had no effect on guinea pig and rabbit myocytes. The properties of adenosine-activated outward current in rat and ferret ventricular myocytes indicated that this current is the adenosine-sensitive K+ current [IK(Ado)]. Adenosine had no significant effect on basal Ca2+ current but specifically inhibited isoproterenol-stimulated L-type Ca2+ current in myocytes of all species studied. Binding studies revealed that the density of A1 adenosine receptors (A1AdoR) was highest in ferret and lowest in rabbit myocytes, but the differential effects of adenosine among species could not be solely explained by differences in A1AdoR density. In summary, adenosine shortened the action potential and reduced the twitch shortening of rat and ferret but not of guinea pig and rabbit ventricular myocytes. Shortening of the action potential was associated with the activation of IK(Ado). The anti-beta-adrenergic action of adenosine appeared to be independent of species.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008564	Membrane Potentials	The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).	Resting Potentials,Transmembrane Potentials,Delta Psi,Resting Membrane Potential,Transmembrane Electrical Potential Difference,Transmembrane Potential Difference,Difference, Transmembrane Potential,Differences, Transmembrane Potential,Membrane Potential,Membrane Potential, Resting,Membrane Potentials, Resting,Potential Difference, Transmembrane,Potential Differences, Transmembrane,Potential, Membrane,Potential, Resting,Potential, Transmembrane,Potentials, Membrane,Potentials, Resting,Potentials, Transmembrane,Resting Membrane Potentials,Resting Potential,Transmembrane Potential,Transmembrane Potential Differences
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
D011817	Rabbits	A burrowing plant-eating mammal with hind limbs that are longer than its fore limbs. It belongs to the family Leporidae of the order Lagomorpha, and in contrast to hares, possesses 22 instead of 24 pairs of chromosomes.	Belgian Hare,New Zealand Rabbit,New Zealand Rabbits,New Zealand White Rabbit,Rabbit,Rabbit, Domestic,Chinchilla Rabbits,NZW Rabbits,New Zealand White Rabbits,Oryctolagus cuniculus,Chinchilla Rabbit,Domestic Rabbit,Domestic Rabbits,Hare, Belgian,NZW Rabbit,Rabbit, Chinchilla,Rabbit, NZW,Rabbit, New Zealand,Rabbits, Chinchilla,Rabbits, Domestic,Rabbits, NZW,Rabbits, New Zealand,Zealand Rabbit, New,Zealand Rabbits, New,cuniculus, Oryctolagus
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D004553	Electric Conductivity	The ability of a substrate to allow the passage of ELECTRONS.	Electrical Conductivity,Conductivity, Electric,Conductivity, Electrical
D005260	Female		Females
D005289	Ferrets	Semidomesticated variety of European polecat much used for hunting RODENTS and/or RABBITS and as a laboratory animal. It is in the subfamily Mustelinae, family MUSTELIDAE.	Domestic Polecat,Domestic Polecats,European Polecat,European Polecats,Ferret,Mustela putorius,Mustela putorius furo,Polecat, Domestic,Polecat, European,Polecats, Domestic,Polecats, European