Human IGR1 cells are a model for malignant melanoma. Since progression through the cell cycle is accompanied by transient cell hyperpolarization, we studied the properties of potassium and chloride ion channels and their impact on cell growth. The major potassium current components were mediated by outward rectifying ether à go-go (hEAG) channels and Ca2+-activated channels (KCa) of the IK/SK type. The major chloride channel component was activated by osmotic cell swelling (Clvol). To infer about the contribution of these channels to proliferation, specific inhibitors are required. Since there is no specific blocker for hEAG available, we used the tricyclic antidepressant imipramine, which blocked all channels mentioned, in combination with blockers for KCa (charybdotoxin) and Clvol (DIDS and pamoic acid). Incubation of IGR1 cells for 48 hr in 10–15 mM imipramine reduced DNA synthesis and metabolism without significant effects on apoptosis. hEAG channels were most sensitive to imipramine (IC50: 3.4 mM at +50 mV), followed by KCa (13.8 mM at +50 mV) and Clvol (12 mM at ?100 mV), indicating that hEAG expression may be of importance for proliferation of melanoma cells. The contribution of KCa channels could be excluded, as 500 nM charybdotoxin, which completely blocked KCa, had no effect on proliferation. The impact of Clvol also seems to be minor, because 500 mM pamoic acid, which completely blocked Clvol, did not affect proliferation either.
The Journal of Membrane Biology – Springer Journals
Published: Jul 1, 2002
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