Cells from ten human meningiomas were electrophysiologically characterized in both living tissue slices and primary cultures. In whole cells, depolarization to voltages higher than +80 mV evoked a large K+ outward current, which could be blocked by iberiotoxin (100 nm) and TEA (half blocking concentration IC50= 5.3 mm). Raising the internal Ca2+ from 10 nm to 2 mm shifted the voltage of half-maximum activation (V 1/2) of the K+ current from +106 to +4 mV. Respective inside-out patch recordings showed a voltage- and Ca2+-activated (BK Ca ) K+ channel with a conductance of 296 pS (130 mm K+ at both sides of the patch). V 1/2 of single-channel currents was +6, −12, −46, and −68 mV in the presence of 1, 10, 100, and 1000 μm Ca2+, respectively, at the internal face of the patch. In cell-attached patches the open probability (P o ) of BK Ca channels was nearly zero at potentials below +80 mV, matching the activation threshold for whole-cell K+ currents with 10 nm Ca2+ in the pipette. Application of 20 μm cytochalasin D increased P o of BK Ca channels in cell-attached patches within minutes. These data suggest that the activation of BK Ca channels in meningioma cells does not only depend on voltage and internal Ca2+ but is also controlled by the cytoskeleton.
The Journal of Membrane Biology – Springer Journals
Published: May 1, 2000
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera