Inhibitory effects of cadmium ion on extracellular Ca2+-independent contraction of rat aorta

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Abstract

In vitro effects of cadmium ion on vasoconstriction, particularly on vasoconstriction independent of extracellular Ca2+, were investigated using isolated rat aorta. Aorta incubation with CdCl2 (0.01, 0.1 mM) significantly attenuated contractile responses to KCl and phenylephrine in the medium containing normal Ca2+ (2.5 mM). The contractile response to phenylephrine in the presence of calcium channel antagonists, nifedipine (1 μM) or verapamil (1 μM), was markedly inhibited by CdCl2 (0.1 mM). In the medium without Ca2+, phenylephrine (10 μM) induced a phasic contraction, which was markedly inhibited by CdCl2 (0.1 mM)/ In the medium without Ca2+, phorbol 12-myristate 13-acetate (1 μM) and okadaic acid (10 μM) caused tonic contractile responses, which were strongly attenuated by CdCl2 (0.1 mM) pretreatment. Contractile response to sodium fluoride (5 ∼ 15 mM) in the absence of extracellular Ca2+ was strongly attenuated by CdCl2 (0.1 mM) pretreatment. These results suggest that cadmium ion depresses an extracellular Ca2+-independent component of agonist-induced vasoconstriction by hindering an intracellular contractile mechanism(s).

References (47)

  • A.A. Abdel-Latif

    Calcium-mobilizing receptors, polyphosphoinositides, and the generation of second messengers

    Pharmacol. Rev.

    (1986)
  • S. Ayotunde et al.

    Mechanism of vascular smooth muscle contraction by sodium fluoride in the isolated aorta of rat and rabbit

    J. Pharmacol. Exp. Ther.

    (1991)
  • R. Balaraman et al.

    Effect of cadmium on contractile response to spasmogens in vascular and nonvascular tissues

    Ind. J. Exp. Biol.

    (1990)
  • C. Bialojan et al.

    Effect of okadaic acid on isometric tension and myosin phosphorylation of chemically skinned guinea-pig taenia coli

    J. Physiol.

    (1988)
  • L. Birnbaumer et al.

    Signal transduction by G proteins

    Kidney Int. (Suppl.)

    (1987)
  • T.B. Bolton

    Mechanisms of action of transmitters and other substances on smooth muscle

    Physiol. Rev.

    (1979)
  • M. Chatterjee et al.

    Phorbol ester-induced contraction in chemically skinned vascular smooth muscle

    Am. J. Physiol.

    (1986)
  • A.T. Chiu et al.

    Ca++ utilization in the constriction of rat aorta to stimulation of protein kinase C by phorbol dibutyrate

    J. Pharmacol. Exp. Ther.

    (1987)
  • D.J. Eakin et al.

    Cadmium and nickel influence on blood pressure, plasma renin, and tissue mineral concentrations

    Am. J. Physiol.

    (1980)
  • C. Eglème et al.

    Enhanced responsiveness of rat isolated aorta to clonidine after removal of the endothelial cells

    Br. J. Pharmacol.

    (1984)
  • J. Forder et al.

    Plasma membrane calcium flux, protein kinase C activation and smooth muscle contraction

    J. Pharmacol. Exp. Ther.

    (1985)
  • J. Fukuda et al.

    Permeation of manganese, cadmium, zinc, and beryllium through calcium channels of an insect muscle membrane

    Science

    (1977)

    Science

    (1977)
  • R.F. Furchgott et al.

    Endothelium-derived relaxing and contracting factors

    FASEB J.

    (1989)

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