Effects of some vasodilators on calcium translocation in intact and fractionated vascular smooth muscle

Thorens, S; Haeusler, G.

doi:10.1016/0014-2999(79)90410-2

Cited by 120 publications

(51 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In our present study on microsomes from human umbilical arteries and of predominantly sarcolemmal origin, none of 15 vasodilator drugs and vasoactive antihypertensives, including the 4 drugs used in the former study, showed any effect on the microsomal Ca2+ uptake at 10-5 M. Negative results with some of these drugs at the same concentration were also obtained in studies on microsomes from bovine carotid arteries (Klinner, Ehlers, Fermum & Meisel, 1977), or from rabbit aorta (Thorens & Haeusler, 1979). Only at considerably higher concentrations (10-4 M or more) did a few of these drugs inhibit the microsomal Ca2+ uptake slightly, but this seems to be of little relevance for the understanding of the mode of action of these drugs.…”

Section: Discussionsupporting

confidence: 59%

EFFECTS OF VASODILATOR DRUGS, ALKALINE PHOSPHTASE, AND CYCLIC AMP‐DEPENDENT PROTEIN KINASE ON THE ⁴⁵CALCIUM UPTAKE OF SARCOLEMMAL MICROSOMES FROM HUMAN UMBILICAL ARTERIES

Kreye

Schlicker

1980

British J Pharmacology

View full text Add to dashboard Cite

A microsomal fraction was prepared from human umbilical arteries by differential centrifugation. The preparation was capable of an oxalate-stimulated Ca2 + uptake at a mean rate of 0.74 nmol Ca2 + mg-I protein min-' which could be inhibited by a Ca2+ ionophore, A 23 187, and by Tween 80.2 The rate of Ca2 + uptake in the fractions obtained by density gradient fractionation paralleled 5'-nucleotidase activity suggesting that vesicles of predominantly sarcolemmal origin were responsible for the microsomal Ca2 ±uptake. 3 Cyclic adenosine 3',5'-monophosphate-dependent protein kinase enhanced membrane phosphorylation but did not affect Ca2+ uptake. Preincubation with alkaline phosphatase reduced membrane phosphorylation to a greater extent than Ca2+ uptake. These data are not in favour of a close correlation between Ca2+ uptake and phosphorylation. 4 None of 15 vasodilator drugs (bencyclane, carbocromen, diazoxide, dilazep, hydralazine, indapamide, isosorbide dinitrate, methyl-isobutyl-xanthine, minoxidil, naftidrofuryl, nitroglycerine, prenylamine, sodium nitroprusside, tetracaine, and verapamil) had any effect on Ca2 + uptake at 10-s M. This suggests that vasodilator drugs do not act by a direct influence on the Ca2+ pumps of vascular smooth muscle cells.

show abstract

Section: Discussionsupporting

confidence: 59%

EFFECTS OF VASODILATOR DRUGS, ALKALINE PHOSPHTASE, AND CYCLIC AMP‐DEPENDENT PROTEIN KINASE ON THE ⁴⁵CALCIUM UPTAKE OF SARCOLEMMAL MICROSOMES FROM HUMAN UMBILICAL ARTERIES

Kreye

Schlicker

1980

British J Pharmacology

View full text Add to dashboard Cite

show abstract

“…The relaxant effects of papaverine and theophylline may involve additional mechanisms. These drugs increase the efflux and uptake of Ca2" by intracellular organelles (Thorens & Haeusler, 1979;Takayanagi et al, 1980;Imai & Kitagawa, 1981;Koike & Takayanagi, 1981;Huddart et al, 1983;Qashi & Takayanagi, 1983) and also inhibit adenosine 3':5'-cyclic monophosphate (cyclic AMP) phosphodiesterase (Weiss & Hait, 1977;Mukai et al, 1981). Furthermore, recent evidence indicates that most of the calcium entry blockers have an additional intracellular site ofaction, related to an increase of Ca2" efflux or to stimulation of Ca2" uptake (Spedding, 1983;Saida & Van Breemen, 1983;Cohen et al, 1984).…”

Section: Discussionmentioning

confidence: 99%

Ketamine‐inhibition of calcium‐induced contractions in depolarized rat uterus: a comparison with other calcium antagonists

Calixto

Loch

1985

British J Pharmacology

View full text Add to dashboard Cite

1 The inhibitory effect of the intravenous anaesthetic ketamine on CaCl2-induced contractions in the isolated K+-depolarized uterus of the rat in Ca2+-free medium was compared with that produced by papaverine, theophylline and the calcium entry blocker verapamil.2 Pre-incubation for 20 min with either ketamine (0.3 to 3 mM), papaverine (3 to 30 IpM), theophylline (0.1 to mM) or verapamil (3 to 30 nM) induced parallel, concentration-dependent rightward displacements of the dose-response curves to Ca2+ (0.04 to 22 mM). The antagonism was competitive, except that due to verapamil, the Schild plot for which yielded a slope which differed significantly from unity. The calculated pA2 values (± s.e.mean) were: ketamine 3.90 ± 0.07; papaverine 5.55 ± 0.05; theophylline 3.99 ± 0.1 and verapamil 9.54 ± 0.24 3 These drugs differed in their ability to relax the sustained contraction induced by Ca2" (1 mM) in K+-depolarizing solution. Ketamine and verapamil relaxed the preparation in a concentrationdependent manner whereas theophylline and especially papaverine were less potent and induced only partial maximal relaxation. The tj of the relaxant effect was significantly less for ketamine than for verapamil (5 and 22 min, respectively). Only ketamine produced a relaxation comparable to that obtained by washing the preparation with Ca2+-free solution (t1 = approx. 5 min). 4 Prior exposure of the depolarized uterine strip to a low concentration of Ca2+ (0.22 mM) increased the potency of ketamine, but decreased that of papaverine and theophylline, in antagonizing Ca2+-induced contractions. In contrast, this procedure did not affect the potency of verapamil. 5 The inhibitory effects of these drugs, excluding those of verapamil, were completely reversed after washing the preparations with a high-potassium Ca2+-free solution, 3-5 times for about 30-60 min. 6 These experiments provide further evidence that the relaxant effect produced by ketamine on the rat isolated uterus is due to its ability to antagonize Ca2+ movements competitively and also show that there are marked differences between the nature of the relaxant effects of ketamine and those of papaverine, theophylline and verapamil.

show abstract

“…This suggests that possible effects of D600 other than that on calcium fluxes should be taken into consideration. Membrane fractions from smooth vascular muscle will have their capability of binding 45Ca reduced when exposed to concentrations of verapamil greater than 1O-5 M (Thorens & Hauesler 1979). Isolated membranes from heart muscle also have a reduced capacity to bind calcium after treatment with verapamil (Nayler, Dunnett & Sullivan 1976).…”

Section: Discussionmentioning

confidence: 99%

Renin release from isolated rat glomeruli: seasonal variations and effects of D600 on the response to calcium deprivation.

Baumbach

Skøtt²

1981

The Journal of Physiology

View full text Add to dashboard Cite

SUMMARY1. The effects of calcium deprivation and D600 on the rate of renin release and seasonal variations in the response were studied on juxtaglomerular cells from a preparation of isolated rat glomeruli superfused in vitro.2. Reduction of superfusate calcium concentration caused an increase in renin release, which was significantly higher during the summer (May-August) than during the rest of the year.3. Addition of D600 (2 x 1O-4 M) to a calcium-free medium in the low responsive period caused a markedly increased renin release. In the high responsive period renin release increased more rapidly and to a higher level initially than observed in the control lines without D660.4. It is suggested that the effect of calcium on renin release predominantly is mediated by changes in calcium bound to the plasma membrane ofthe juxtaglomerular cell. The sensitivity of this cell to changes in the extracellular calcium concentration seems to be regulated and varies with season, possibly due to regulation of the amount of calcium bound to the membrane.

show abstract

Effects of some vasodilators on calcium translocation in intact and fractionated vascular smooth muscle

Cited by 120 publications

References 27 publications

EFFECTS OF VASODILATOR DRUGS, ALKALINE PHOSPHTASE, AND CYCLIC AMP‐DEPENDENT PROTEIN KINASE ON THE ⁴⁵CALCIUM UPTAKE OF SARCOLEMMAL MICROSOMES FROM HUMAN UMBILICAL ARTERIES

EFFECTS OF VASODILATOR DRUGS, ALKALINE PHOSPHTASE, AND CYCLIC AMP‐DEPENDENT PROTEIN KINASE ON THE ⁴⁵CALCIUM UPTAKE OF SARCOLEMMAL MICROSOMES FROM HUMAN UMBILICAL ARTERIES

Ketamine‐inhibition of calcium‐induced contractions in depolarized rat uterus: a comparison with other calcium antagonists

Renin release from isolated rat glomeruli: seasonal variations and effects of D600 on the response to calcium deprivation.

Contact Info

Product

Resources

About

Effects of some vasodilators on calcium translocation in intact and fractionated vascular smooth muscle

Cited by 120 publications

References 27 publications

EFFECTS OF VASODILATOR DRUGS, ALKALINE PHOSPHTASE, AND CYCLIC AMP‐DEPENDENT PROTEIN KINASE ON THE 45CALCIUM UPTAKE OF SARCOLEMMAL MICROSOMES FROM HUMAN UMBILICAL ARTERIES

EFFECTS OF VASODILATOR DRUGS, ALKALINE PHOSPHTASE, AND CYCLIC AMP‐DEPENDENT PROTEIN KINASE ON THE 45CALCIUM UPTAKE OF SARCOLEMMAL MICROSOMES FROM HUMAN UMBILICAL ARTERIES

Ketamine‐inhibition of calcium‐induced contractions in depolarized rat uterus: a comparison with other calcium antagonists

Renin release from isolated rat glomeruli: seasonal variations and effects of D600 on the response to calcium deprivation.

Contact Info

Product

Resources

About

EFFECTS OF VASODILATOR DRUGS, ALKALINE PHOSPHTASE, AND CYCLIC AMP‐DEPENDENT PROTEIN KINASE ON THE ⁴⁵CALCIUM UPTAKE OF SARCOLEMMAL MICROSOMES FROM HUMAN UMBILICAL ARTERIES

EFFECTS OF VASODILATOR DRUGS, ALKALINE PHOSPHTASE, AND CYCLIC AMP‐DEPENDENT PROTEIN KINASE ON THE ⁴⁵CALCIUM UPTAKE OF SARCOLEMMAL MICROSOMES FROM HUMAN UMBILICAL ARTERIES