Abstract
Depolarization with 50 mM K+ increased 45Ca2+ uptake into neuronal clonal cell lines NG108-15, NIE-115 and NH15-CA2. In each cell line this depolarization-induced uptake was blocked by inorganic and organic blockers of voltage sensitive calcium channels. However, tetrodotoxin (10-6M) was ineffective. Moreover, in the presence of tetrodotoxin, neither batrachotoxin nor veratridine inhibited the depolarization-induced uptake. The novel dihydropyridine BAY K8644 enhanced depolarization-induced 45Ca2+ uptake into each cell line in a nitrendipine reversible fashion. In the presence of tetrodotoxin, the BAY K8644/50 mM K+ stimulated uptake could be partially inhibited by batrachotoxin (10-6M) and veratridine (5 x 10-5 M). These effects were not altered by the presence of scorpion venom (1 μg/ml). The results indicate that both batrachotoxin and veratridine can modulate the affects of dihydropyridines on the gating properties of voltage sensitive calcium channels.
Original language | English (US) |
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Pages (from-to) | 1493-1501 |
Number of pages | 9 |
Journal | Life Sciences |
Volume | 36 |
Issue number | 15 |
DOIs | |
State | Published - Apr 15 1985 |
Funding
The authors would like to thank Drs. Glyn Dawson and Mitchel Villereal for the generous use of their tissue culture facilities, Elisabeth Cornelison for technical assistance and Della Akres for expert preparation of the manuscript. This study was supported by NIH grants DA-02121 and DA-02575 to R.J.M. S.B.F. was a NATO (United Kingdom) Fellow.
ASJC Scopus subject areas
- General Biochemistry, Genetics and Molecular Biology
- Pharmacology, Toxicology and Pharmaceutics(all)