Myocardial TRPC6-mediated Zn<sup>2+</sup> influx induces beneficial positive inotropy through β-adrenoceptors
Baroreflex control of cardiac contraction (positive inotropy) through sympathetic nerve activation is important for cardiocirculatory homeostasis. Transient receptor potential canonical subfamily (TRPC) channels are responsible for α1-adrenoceptor (α1AR)-stimulated cation entry and their upregulatio...
Saved in:
| Main Author: | |
|---|---|
| Other Authors: | |
| Format: | Article |
| Published: |
2023
|
| Subjects: | |
| Online Access: | https://repository.li.mahidol.ac.th/handle/123456789/83519 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Institution: | Mahidol University |
| Summary: | Baroreflex control of cardiac contraction (positive inotropy) through sympathetic nerve activation is important for cardiocirculatory homeostasis. Transient receptor potential canonical subfamily (TRPC) channels are responsible for α1-adrenoceptor (α1AR)-stimulated cation entry and their upregulation is associated with pathological cardiac remodeling. Whether TRPC channels participate in physiological pump functions remains unclear. We demonstrate that TRPC6-specific Zn2+ influx potentiates β-adrenoceptor (βAR)-stimulated positive inotropy in rodent cardiomyocytes. Deletion of trpc6 impairs sympathetic nerve–activated positive inotropy but not chronotropy in mice. TRPC6-mediated Zn2+ influx boosts α1AR-stimulated βAR/Gs-dependent signaling in rat cardiomyocytes by inhibiting β-arrestin-mediated βAR internalization. Replacing two TRPC6-specific amino acids in the pore region with TRPC3 residues diminishes the α1AR-stimulated Zn2+ influx and positive inotropic response. Pharmacological enhancement of TRPC6-mediated Zn2+ influx prevents chronic heart failure progression in mice. Our data demonstrate that TRPC6-mediated Zn2+ influx with α1AR stimulation enhances baroreflex-induced positive inotropy, which may be a new therapeutic strategy for chronic heart failure. |
|---|