Biomaterial Database

Myocardial potassium uptake during alpha- and beta-adrenoceptor stimulation. 1987

O Ellingsen, and O A Vengen, and A Ilebekk

Institute for Experimental Medical Research, Ullevaal Hospital, University of Oslo, Norway.

The changes in myocardial K+ balance during alpha- and beta-adrenoceptor stimulation were compared in 10 anesthetized open-chest pigs by intracoronary isoproterenol and phenylephrine infusions. K+ concentration was continuously recorded by polyvinyl chloride catheter-valinomycin minielectrodes in arterial and coronary sinus blood. The arterial-coronary sinus difference and accumulated myocardial K+ uptake were calculated after computerized data sampling. Isoproterenol (2.5 nmol/min ic) reduced coronary sinus K+ transiently to a nadir of 0.37 (0.23-0.53) mM (median and 95% confidence interval) below control. The accumulated K+ uptake amounted to 139 (63-215) mumol/100 g. After beta-blockade by propranolol, phenylephrine (100 nmol/min ic) induced a transient coronary sinus K+ lowering of 0.16 (0.13-0.21) mM and an accumulated K+ uptake of 30 (20-41) mumol/100 g, both values less than those of isoproterenol (P less than 0.001). Myocardial contractility increased only during isoproterenol infusion, arterial blood pressure rose slightly by phenylephrine, but changes in myocardial O2 extraction and lactate uptake did not indicate cardiac ischemia. We conclude that both alpha- and beta-adrenoceptor stimulation induce a myocardial K+ uptake presumably due to increased Na-K pump activity, the latter more efficiently.

UI	MeSH Term	Description	Entries
D007545	Isoproterenol	Isopropyl analog of EPINEPHRINE; beta-sympathomimetic that acts on the heart, bronchi, skeletal muscle, alimentary tract, etc. It is used mainly as bronchodilator and heart stimulant.	Isoprenaline,Isopropylarterenol,4-(1-Hydroxy-2-((1-methylethyl)amino)ethyl)-1,2-benzenediol,Euspiran,Isadrin,Isadrine,Isopropyl Noradrenaline,Isopropylnoradrenaline,Isopropylnorepinephrine,Isoproterenol Hydrochloride,Isoproterenol Sulfate,Isuprel,Izadrin,Norisodrine,Novodrin,Hydrochloride, Isoproterenol,Noradrenaline, Isopropyl,Sulfate, Isoproterenol
D007773	Lactates	Salts or esters of LACTIC ACID containing the general formula CH3CHOHCOOR.
D008297	Male		Males
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
D010101	Oxygen Consumption	The rate at which oxygen is used by a tissue; microliters of oxygen STPD used per milligram of tissue per hour; the rate at which oxygen enters the blood from alveolar gas, equal in the steady state to the consumption of oxygen by tissue metabolism throughout the body. (Stedman, 25th ed, p346)	Consumption, Oxygen,Consumptions, Oxygen,Oxygen Consumptions
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.
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D005260	Female		Females
D005947	Glucose	A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement.	Dextrose,Anhydrous Dextrose,D-Glucose,Glucose Monohydrate,Glucose, (DL)-Isomer,Glucose, (alpha-D)-Isomer,Glucose, (beta-D)-Isomer,D Glucose,Dextrose, Anhydrous,Monohydrate, Glucose
D006439	Hemodynamics	The movement and the forces involved in the movement of the blood through the CARDIOVASCULAR SYSTEM.	Hemodynamic