Characterization of voltage-sensitive calcium channels in growth plate chondrocytes

Biochemical and Biophysical Research Communications
M J ZuscikR N Rosier

Abstract

Growth plate chondrocytes (GPCs), cells integrally involved with the process of endochondral bone formation, facilitate Ca2+ infux to provide a source of ion for processes such as Ca2+ signaling and matrix vesicle loading. We hypothesize that this Ca2+ entry into GPCs is achieved through the action of voltage-sensitive Ca2+ channels. This hypothesis was tested by measuring intracellular [Ca2+] changes in fura 2-loaded GPCs that were depolarized by challenge with a K(+)-containing medium. KCl doses between 55 and 95 mM evoked significant Ca2+ responses that were blocked by addition of extracellular EGTA. The Ca2+ response evoked by 95 mM K+ was insensitive to 100 microM doses of nifedipine or nitrendipine, ruling out L-type channel involvement. This finding was corroborated by the observation that 10 microM BAY K 8644 did not activate a Ca2+ response of its own. However, 10 microM Cd2+ significantly inhibited the 95 mM Ks(+)-evoked effects, suggesting N-type channel activity. Use of 1 microM Ni+ in an attempt to block possible T-type channel activity caused nonspecific cellular effects, precluding pharmacological assessment of a possible T-type channel activity. These data (i) provide the first direct evidence for voltage-sensit...Continue Reading

Citations

Jun 22, 1999·Journal of Orthopaedic Research : Official Publication of the Orthopaedic Research Society·F GuilakH J Donahue
Jun 5, 2002·The Journal of Cell Biology·Wei Wang, Thorsten Kirsch
May 20, 2015·Current Rheumatology Reports·Csaba MattaAli Mobasheri
Oct 18, 2002·Journal of Orthopaedic Research : Official Publication of the Orthopaedic Research Society·Michael J ZuscikRandy N Rosier
Jan 24, 2007·Journal of Cellular Biochemistry·Edna E MancillaAnnelise Goecke
Sep 21, 2018·Frontiers in Physiology·Mary M MaleckarWayne R Giles
Aug 2, 2005·Developmental Dynamics : an Official Publication of the American Association of Anatomists·Ying ShaoMary C Farach-Carson
Sep 27, 2018·Philosophical Transactions of the Royal Society of London. Series B, Biological Sciences·Cristian ParisiNiamh C Nowlan

❮ Previous
Next ❯

Related Concepts

Related Feeds

Calcium & Bioenergetics

Bioenergetic processes, including cellular respiration and photosynthesis, concern the transformation of energy by cells. Here is the latest research on the role of calcium in bioenergetics.

Related Papers

Biochemical and Biophysical Research Communications
J W MozrzymasF Ruzzier
International Review of Cytology
Geoffrey E WoodardJuan A Rosado
Cellular Physiology and Biochemistry : International Journal of Experimental Cellular Physiology, Biochemistry, and Pharmacology
Simon MoussaudHenning J Draheim
© 2021 Meta ULC. All rights reserved