Voltage dependent calcium channels in adrenal glomerulosa cells and in insulin producing cells.
Cell Calcium
; 23(1): 33-42, 1998 Jan.
Article
em En
| MEDLINE
| ID: mdl-9570008
ABSTRACT
We have examined the structure and function of Ca2+ channels in excitable endocrine cell types, in rat adrenal glomerulosa cells and in two insulin producing cell types, the rat pancreatic beta cell and the INS-1 cell line. In previous studies on glomerulosa cells, we observed low (T-type) and high threshold (L-type) voltage dependent Ca2+ currents in addition to a K+ induced inward rectifying Ca2+ current (Igl). beta cells are known to exhibit T-, L- and N-type currents. We have now found that INS-1 cells also show low threshold (T-type) and high threshold Ca2+ currents. The latter was further resolved by organic inhibitors into L-type and P/Q-type currents and no Igl was detected. The expression of the pore-forming alpha 1 subunit of voltage dependent Ca2+ channels was studied by means of reverse transcription-polymerase chain reaction (RT-PCR), followed by restriction enzyme mapping and/or sequencing. Both in glomerulosa and pancreatic beta cells, the neuroendocrine (D) class of the alpha 1 subunit, known to be responsible for L-type current, represents the majority of the PCR product. Comparable amounts of the neuroendocrine (D) and the neuronal A-type alpha 1 subunits dominate the message in INS-1 cells. Different characteristics of Ca2+ currents in these cell types is discussed in view of the channel repertoire.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Venenos de Aranha
/
Canais de Cálcio
/
Zona Glomerulosa
/
Cálcio
/
Ilhotas Pancreáticas
/
Canais de Cálcio Tipo N
Limite:
Animals
Idioma:
En
Revista:
Cell Calcium
Ano de publicação:
1998
Tipo de documento:
Article
País de afiliação:
Hungria