Noradrenaline and heart contraction. Animation showing the mechanism by which the hormone noradrenaline affects heart contraction, as mediated by G proteins. At upper left, the hormone binds to its receptor on the heart muscle cell membrane (sarcolemma). This triggers a GPCR (G protein-coupled receptor) mechanism that binds to adenylate cyclase (blue). This activates the formation of cyclic AMP (AMPc). This second messenger induces in its turn a phosphorylation pathway (intermediate protein, centre) which results in the opening of a calcium membrane channel (upper right). The entry of calcium ions (green) triggers the contraction of the cardiac muscle (heart shown at lower right). The detail of the binding of calcium to troponin in the actin-myosin system is shown at bottom centre. For this animation with labels, see K004/4747. | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Biocosmos / Francis Leroy & Maxime Deroyer |
Modell-Rechte: | nicht erforderlich |
Länge: | 40 Sekunden |
Seitenverhältnis: | 16:9 |
Restrictions: | - |