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Literature DB >> 6322898

Evidence that the positive inotropic effects of the alkylxanthines are not due to adenosine receptor blockade.

Abstract

We investigated the possibility that the positive inotropic effects of the alkylxanthines are due to adenosine receptor blockade. The potency of 8-phenyltheophylline, theophylline and enprofylline as adenosine antagonists was assessed in vitro, using the guinea-pig isolated atrium, and in vivo, using the anaesthetized dog. The order of potency of the alkylxanthines as antagonists of the negative inotropic response to 2-chloroadenosine in vitro, and of the hypotensive response to adenosine in vivo was 8-phenyltheophylline greater than theophylline greater than enprofylline. The order of potency of the alkylxanthines as positive inotropic and chronotropic agents in the anaesthetized dog was enprofylline greater than theophylline greater than 8-phenyltheophylline. The results of this study indicate that the inotropic effects of the alkylxanthines in the anaesthetized dog are not due to adenosine receptor blockade.

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Year: 1984 PMID： 6322898 PMCID： PMC1986898 DOI： 10.1111/j.1476-5381.1984.tb10092.x

Source DB: PubMed Journal: Br J Pharmacol ISSN： 0007-1188 Impact factor: 8.739

18 in total

1. Alkylxanthines: inhibition of adenosine-elicited accumulation of cyclic AMP in brain slices and of brain phosphodiesterase activity.

Authors: F W Smellie; C W Davis; J W Daly; J N Wells
Journal: Life Sci Date: 1979-06-25 Impact factor: 5.037

2. Influence of caffeine and other methylxanthines on mechanical properties of isolated mammalian heart muscle. Evidence for a dual mechanism of action.

Authors: J R Blinks; C B Olson; B R Jewell; P Bravený
Journal: Circ Res Date: 1972-04 Impact factor: 17.367

3. A species difference in the uptake of adenosine by heart.

Authors: S V Hopkins; R G Goldie
Journal: Biochem Pharmacol Date: 1971-12 Impact factor: 5.858

4. Changes in the calculated myocardial oxygen consumption during adenosine infusion versus estimates of developed tension and velocity of contraction.

Authors: J Lammerant; I Becsei; J Mertens-Strijthagen; C De Schryver
Journal: Arch Int Pharmacodyn Ther Date: 1970-07

5. The chronotropic action of ATP and related compounds studied by direct perfusion of the sinus node.

Authors: T N James
Journal: J Pharmacol Exp Ther Date: 1965-08 Impact factor: 4.030

6. Inhibitory effect of adenosine on adrenergic neuroeffector transmission in the rabbit heart.

Authors: P Hedqvist; B B Fredholm
Journal: Acta Physiol Scand Date: 1979-01

7. Changes in adenosine and glycogen phosphorylase activity during the cardiac cycle.

Authors: C I Thompson; R Rubio; R M Berne
Journal: Am J Physiol Date: 1980-03

8. Effect of aminophylline on urinary excretion of epinephrine and norepinephrine in man.

Authors: N O Atuk; M C Blaydes; F B Westervelt; J E Wood
Journal: Circulation Date: 1967-04 Impact factor: 29.690

9. Inhibition of cardiac sympathetic neurotransmission by adenosine.

Authors: M F Lokhandwala
Journal: Eur J Pharmacol Date: 1979-12-20 Impact factor: 4.432

10. Left ventricular contractility and developed tension in the intact dog submitted to an intracoronary infusion of adenosine.

Authors: J Lammerant; I Becsei
Journal: J Physiol Date: 1973-02 Impact factor: 5.182

5 in total

Evidence that the positive inotropic effects of the alkylxanthines are not due to adenosine receptor blockade.

1. Alkylxanthines: inhibition of adenosine-elicited accumulation of cyclic AMP in brain slices and of brain phosphodiesterase activity.

2. Influence of caffeine and other methylxanthines on mechanical properties of isolated mammalian heart muscle. Evidence for a dual mechanism of action.

3. A species difference in the uptake of adenosine by heart.

4. Changes in the calculated myocardial oxygen consumption during adenosine infusion versus estimates of developed tension and velocity of contraction.

5. The chronotropic action of ATP and related compounds studied by direct perfusion of the sinus node.

6. Inhibitory effect of adenosine on adrenergic neuroeffector transmission in the rabbit heart.

7. Changes in adenosine and glycogen phosphorylase activity during the cardiac cycle.

8. Effect of aminophylline on urinary excretion of epinephrine and norepinephrine in man.

9. Inhibition of cardiac sympathetic neurotransmission by adenosine.

10. Left ventricular contractility and developed tension in the intact dog submitted to an intracoronary infusion of adenosine.

1. Endogenous adenosine improves work rate to oxygen consumption ratio in catecholamine stimulated isovolumic rat heart.

2. Mediation by adenosine of bradycardia in rat heart during graded global ischaemia.

3. Effect of the adenosine antagonist 8-phenyltheophylline on glycerol-induced acute renal failure in the rat.

4. A caffeine analogue (1,3,7-trimethyl-6-thioxo-2-oxopurine) with a negative inotropic and chronotropic effect.

5. Amelioration of cisplatin-induced acute renal failure with 8-cyclopentyl-1,3-dipropylxanthine.