Comparative identification of Ca2+ channel expression in INS-1 and rat pancreatic beta cells.
OBJECTIVE
To identify and compare the profile of Ca(2+) channel subunit expression in INS-1 and rat pancreatic beta cells.


METHODS
The rat insulin-secreting INS-1 cell line was cultured in RPMI-1640 with Wistar rats employed as islet donors. Ca(2+) channel subunit expression in INS-1 and isolated rat beta cells were examined by reverse transcription polymerase chain reaction (RT-PCR). Absolute real-time quantitative PCR was performed in a Bio-Rad iQ5 Gradient Real Time PCR system and the data analyzed using an iQ5 system to identify the expression level of the Ca(2+) channel subunits.


RESULTS
In INS-1 cells, the L-type Ca(2+) channel 1C subunit had the highest expression level and the TPRM2 subunit had the second highest expression. In rat beta cells, the TPRC4beta subunit expression was dominant and the expression of the L-type 1C subunit exceeded the 1D subunit expression about two-fold. This result agreed with other studies, confirming the important role of the L-type 1C subunit in insulin-secreting cells, and suggested that non-voltage-operated Ca(2+) channels may have an important role in biphasic insulin secretion.


CONCLUSIONS
Twelve major Ca(2+) channel subunit types were identified in INS-1 and rat beta cells and significant differences were observed in the expression of certain subunits between these cells.
Li
Fei
F
Department of General Surgery, Digestive Medical Center, The First Affiliated Hospital, Medical School, Tsinghua University, Beijing, China.
Zhang
Zong-Ming
ZM
D000818:Animals; D015220:Calcium Channels / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line / Q000378:metabolism*; D006801:Humans; D050417:Insulin-Secreting Cells / Q000166:cytology / Q000378:metabolism*; D008297:Male; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar
D015220:Calcium Channels; D021122:Protein Subunits; D012333:RNA, Messenger