Involvement of TRPC3 channels in calcium oscillations mediated by OX1 orexin receptors |
| |
Authors: | Hanna M. Peltonen,Genevieve Bart,Miia S.H. Antikainen,Karl E. Å kerman |
| |
Affiliation: | a A. I. Virtanen Institute for Molecular Sciences, Department of Neurobiology, University of Kuopio, POB 1627, FI-70211 Kuopio, Finland b Department of Basic Veterinary Sciences, Biochemistry, POB 66, FI-00014 University of Helsinki, Finland c Institute of Biomedicine/Physiology, POB 63, Biomedicum Helsinki, FI-00014 University of Helsinki, Finland |
| |
Abstract: | Oscillations of intracellular Ca2+ provide a novel mechanism for sustained activation of cellular processes. Receptor-activated oscillations are mainly thought to occur through rhythmic IP3-dependent store discharge. However, as shown here in HEK293 cells 1 nM orexin-A (Ox-A) acting at OX1 receptors (OX1R) triggered oscillatory Ca2+ responses, requiring external Ca2+. These responses were attenuated by interference with TRPC3 channel (but not TRPC1/4) function using dominant negative constructs, elevated Mg2+ (a blocker of many TRP channels) or inhibition of phospholipase A2. These treatments did not affect Ca2+ oscillations elicited by high concentrations of Ox-A (100 nM) in the absence of external Ca2+. OX1R are thus able to activate TRPC(3)-channel-dependent oscillatory responses independently of store discharge. |
| |
Keywords: | Calcium oscillations Orexin-A Hypocretin-1 OX1 receptor Receptor TRP channel Phospholipase A2 |
本文献已被 ScienceDirect 等数据库收录! |
|