dc.contributor.author |
Okada, Yukio |
|
dc.contributor.author |
Imendra, K. G. |
|
dc.contributor.author |
Miyazaki, Toshihiro |
|
dc.contributor.author |
Hotokezaka, Hitoshi |
|
dc.contributor.author |
Fujiyama, Rie |
|
dc.contributor.author |
Zeredo, Jorge L. |
|
dc.contributor.author |
Miyamoto, Takenori |
|
dc.contributor.author |
Toda, Kazuo |
|
dc.date.accessioned |
2023-01-17T06:19:39Z |
|
dc.date.available |
2023-01-17T06:19:39Z |
|
dc.date.issued |
2005-12-15 |
|
dc.identifier.citation |
Okada, Y., Imendra, K. G., Miyazaki, T., Hotokezaka, H., Fujiyama, R., Zeredo, J. L., ... & Toda, K. (2005). Biophysical properties of voltage-gated Na+ channels in frog parathyroid cells and their modulation by cannabinoids. Journal of experimental biology, 208(24), 4747-4756. |
en_US |
dc.identifier.issn |
0022- 0949 |
|
dc.identifier.uri |
http://ir.lib.ruh.ac.lk/xmlui/handle/iruor/10193 |
|
dc.description.abstract |
The membrane properties of isolated frog parathyroid
cells were studied using perforated and conventional
whole-cell patch-clamp techniques. Frog parathyroid cells
displayed transient inward currents in response to
depolarizing pulses from a holding potential of –84·mV.
We analyzed the biophysical properties of the inward
currents. The inward currents disappeared by the
replacement of external Na+ with NMDG+ and were
reversibly inhibited by 3· mol·l
–1 TTX, indicating that the
currents occur through the TTX-sensitive voltage-gated
Na+ channels. Current density elicited by a voltage step
from –84·mV to –24·mV was –80·pA·pF–1 in perforated
mode and –55·pA·pF–1 in conventional mode. Current
density was decreased to –12·pA·pF–1 by internal GTP S
(0.5·mmol·l
–1), but not affected by internal GDP S
(1·mmol·l
-1). The voltage of half-maximum (V1/2)
activation was –46·mV in both perforated and
conventional modes. V1/2 of inactivation was –80·mV in
perforated mode and –86·mV in conventional mode.
Internal GTP S (0.5·mmol·l
–1) shifted the V1/2 for
activation to –36·mV and for inactivation to –98·mV. A
putative endocannabinoid, 2-arachidonoylglycerol ether
(2-AG ether, 50· mol·l
–1) and a cannabinomimetic
aminoalkylindole, WIN 55,212-2 (10· mol·l
–1) also greatly
reduced the Na+ current and shifted the V1/2 for activation
and inactivation. The results suggest that the Na+ currents
in frog parathyroid cells can be modulated by
cannabinoids via a G protein-dependent mechanism. |
en_US |
dc.language.iso |
en |
en_US |
dc.publisher |
The Company of Biologists (United Kingdom) |
en_US |
dc.subject |
parathyroid |
en_US |
dc.subject |
voltage-gated Na+ channel |
en_US |
dc.subject |
G protein |
en_US |
dc.subject |
activation |
en_US |
dc.subject |
inactivation |
en_US |
dc.subject |
cannabinoid |
en_US |
dc.subject |
frog |
en_US |
dc.title |
Biophysical properties of voltage-gated Na+ channels in frog parathyroid cells and their modulation by cannabinoids |
en_US |
dc.type |
Article |
en_US |