Reduction of insulin secretion in the insulinoma cell line INS-1 by overexpression of a Ca(v)2.3 (alpha1E) calcium channel antisense cassette
| Autor: | Jürgen Hescheler, Toni Schneider, Udo Klöckner, Alexey Pereverzev, Gabriele Pfitzer, Rolf Vajna |
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| Rok vydání: | 2002 |
| Předmět: |
medicine.medical_specialty
DNA Complementary Endocrinology Diabetes and Metabolism medicine.medical_treatment Blotting Western Green Fluorescent Proteins Calcium Channels R-Type Biology Transfection DNA Antisense Endocrinology Internal medicine Complementary DNA Insulin Secretion Sense (molecular biology) Tumor Cells Cultured medicine Humans Insulin Cation Transport Proteins Insulinoma Reverse Transcriptase Polymerase Chain Reaction Calcium channel General Medicine medicine.disease Molecular biology Up-Regulation Antisense RNA Gene Expression Regulation Neoplastic Luminescent Proteins Mutagenesis Insertional Cell culture Indicators and Reagents Calcium Channels |
| Zdroj: | European Journal of Endocrinology. :881-889 |
| ISSN: | 1479-683X 0804-4643 |
| Popis: | OBJECTIVE: Multiple types of voltage-activated Ca(2+) channels (T, L, N, P, Q and R type) coordinate a variety of Ca(2+)-dependent processes in neurons and neuroendocrine cells. In insulinoma cell lines as well as in endocrine tissues, the non-L-type alpha1E (Ca(v)2.3) subunit is expressed as the tissue-specific splice variant alpha1Ee. DESIGN AND METHODS: To understand the functional role of alpha1E-containing Ca(2+) channels, antisense alpha1E mRNA was overexpressed in INS-1 cells by stable transfection of an antisense alpha1E cassette cDNA. As controls, either a sense alpha1E cassette or a control vector containing enhanced green fluorescent protein as an unrelated gene was stably transfected. The overexpression of each transfected cassette cDNA was recorded by RT-PCR. RESULTS: In three independent antisense alpha1E INS-1 clones, the glucose-induced insulin release was significantly reduced as compared with wild-type INS-1 cells and with a sense alpha1E INS-1 clone. However, in the antisense INS-1 clones, the KCl-induced insulin release was less impaired by overexpressing the antisense alpha1E cassette than the glucose-induced insulin release, leading to the assumption that glucose (15 mmol/l) and KCl (25 mmol/l) finally depolarize the membrane potential to a different extent. CONCLUSION: alpha1E is involved in glucose-induced insulin secretion probably by influencing the excitability of INS-1 cells. |
| Databáze: | OpenAIRE |
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