Abstract
When an action potential excites a fish cardiac myocyte it causes intracellular calcium (Ca) levels to rise initiating contraction. This sequence of events is termed ‘excitation–contraction coupling’. To end contraction and begin relaxation, Ca levels inside the myocyte must fall. This transient rise and fall of Ca with each contraction–relaxation cycle is called the ‘Ca transient’. A contraction–relaxation cycle is the cellular equivalent of the heartbeat. The rate and magnitude of the Ca transient determines the rate and strength of heart contraction. In fish, the Ca fluxes that generate this Ca transient can be of both extra- or intracellular origin and are regulated to adjust cardiac function in a response to a change in physiological demand.
| Original language | English |
|---|---|
| Title of host publication | Encyclopedia of Fish Physiology |
| Subtitle of host publication | From Genome to Environment: Volume 1-3 |
| Place of Publication | San Diego |
| Publisher | Elsevier Masson s.r.l. |
| Pages | 1045-1053 |
| Number of pages | 9 |
| Volume | 1-3 |
| ISBN (Electronic) | 9780123745453 |
| ISBN (Print) | 9780080923239 |
| DOIs | |
| Publication status | Published - 1 Jan 2011 |
Keywords
- Adrenaline
- Ca transient
- Excitation–contraction coupling
- L-type Ca channel
- Myocyte
- Na–Ca exchanger
- Sarcoplasmic reticulum
- Temperature
- Δ[Ca]