EurekaMag.com logo
+ Site Statistics
References:
47,893,527
Abstracts:
28,296,643
+ Search Articles
+ Subscribe to Site Feeds
EurekaMag Most Shared ContentMost Shared
EurekaMag PDF Full Text ContentPDF Full Text
+ PDF Full Text
Request PDF Full TextRequest PDF Full Text
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter
Follow on Google+Follow on Google+
Follow on LinkedInFollow on LinkedIn

+ Translate

Different blocking effects of cadmium and mercury on the early outward current in myocardial mouse cells


, : Different blocking effects of cadmium and mercury on the early outward current in myocardial mouse cells. General Physiology & Biophysics 7(4): 345-352

The effects of external Cd++ and Hg++ on the early outward current (IEO) in myocardial mouse cells were studied using voltage clamp with one suction pipette. Both Cd++ in the millimolar and Hg++ in the micromolar range shifted the half time to peak IEO to positive potentials more than the current amplitude after 50 ms. Incomplete blocking of IEO could be obtained by Cd++ concentrations between 10-3 and 2 .times. 10-2 mol/l and by Hg++ concentrations between 10-6 and 5 .times. 10-5 mol/l. The current-voltage relationships of IEO at peak time and at 50 ms were mainly shifted to the right by Cd++ whereas Hg++ mainly decreased the slope. At incomplete blocking concentrations Cd++ slowed down IEO activation more strongly than did Hg++. All Cd++ effects were completely reversible. The action of Hg++ was irreversible. It is concluded that both ions act directly on the gating machinery of the channels rather than simply binding to homogenous surface charges.


Accession: 005151944

Submit PDF Full Text: Here


Submit PDF Full Text

No spam - Every submission is manually reviewed

Due to poor quality, we do not accept files from Researchgate

Submitted PDF Full Texts will always be free for everyone
(We only charge for PDFs that we need to acquire)

Select a PDF file:
Close
Close

Related references

Benndorf, K.; Nilius, B., 1988: Different blocking effects of Cd++ and Hg++ on the early outward current in myocardial mouse cells. The effects of external Cd++ and Hg++ on the early outward current (IEO) in myocardial mouse cells were studied using voltage clamp with one suction pipette. Both Cd++ in the millimolar and Hg++ in the micromolar range shifted the half time to pea...

Benndorf, K., 1988: Three types of single K channels contribute to the transient outward current in myocardial mouse cells. Whole cell currents and single channel currents were measured by a patch clamp technique in single adult cardiocytes of mice. By stepping from Vh = -70 mV into depolarizing direction nonlinear transient whole cell currents could be elicited at tes...

Doepner, B.; Thierfelder, S.; Hirche, H.; Benndorf, K., 1997: 3-hydroxybutyrate blocks the transient K+ outward current in myocardial mouse cells in a stereoselective fashion. 1. Mouse ventricular myocytes develop a large transient K+ outward current (I(TO)) which accelerates repolarization and is a crucial determinant for the regulation of the action potential duration at various heart rates. The effect of 3-hydroxybut...

Benndorf, K.; Nilius, B., 1988: Properties of an early outward current in single cells of the mouse ventricle. Single ventricular myocytes of adult mice were prepared by enzymatic dissociation for voltage clamp experiments with the one suction pipette dialysis method. After blocking the Na current by 10-4 mol/l TTX early outward currents (IEO) with incompl...

Benndorf K., 1988: Three types of single potassium channels contribute to the transient outward current in myocardial mouse cells. Whole cell currents and single channel currents were measured by a patch clamp technique in single adult cardiocytes of mice. By stepping from Vh = -70 mV into depolarizing direction nonlinear transient whole cell currents could be elicited at tes...

Liu, Q.Y.; Wang, X.L., 1997: The blocking effects of six antiarrhythmic drugs on transient outward current in rat ventricular myocytes. The effects of six antiarrhythmic drugs on transient outward current (I-to) in rat ventricular myocytes were examined by using the patch-clamp whole-cell recording technique. Quinidine, nifedipine, and imipramine resulted in a concentration-depend...

Li, Q.; Keung, E.C., 1994: Effects of myocardial hypertrophy on transient outward current. In the one-clip, two-kidney model of hypertensive rat, a gradual chronic pressure overload is imposed on the heart. Myocardial hypertrophy resulting from such pressure overload is associated with an increased but slower inactivating L-type calcium...

Keung E.C.; Berg R.; Katzung B.G., 1987: Effects of myocardial hypertrophy on transient outward current i a. Circulation 76(4 PART 2): IV-237

Josephson, I.R.; Sanchez-Chapula, J.; Brown, A.M., 1984: Early outward current in rat single ventricular cells. Voltage clamp experiments were conducted using single ventricular myocytes which had been dissociated enzymatically from adult rat hearts in order to examine further the membrane currents which contribute to the unusual plateau of the rat action p...

L.G.and, B.; Deroubaix, E.; Couétil, J.P.; Coraboeuf, E., 1992: Effects of atrionatriuretic factor on Ca2+ current and Cai-independent transient outward K+ current in human atrial cells. The effect of 10 nM atrial natriuretic peptide (ANF) on macroscopic L-type calcium current, ICa, and calcium-independent outward potassium current, Ilo, were studied in myocytes isolated from human atrial trabeculae using the whole-cell-recording...