Cocaine mechanism of action. Animation showing the normal function of dopamine at a synapse (junction between two nerve cells) and then what happens when cocaine is present. A nerve signal travels (from left to right) towards the presynaptic membrane (centre left) of the neuron (nerve cell), where it triggers the release of the neurotransmitter dopamine (blue ovals). The dopamine molecules bind to receptors (yellow) on the postsynaptic membrane (centre right), opening ion channels that transport sodium ions (red) into the cell. This propagates the nerve signal. The dopamine is released from the receptors and taken up by the the presynaptic cell to be recycled. Cocaine (green) blocks this reuptake, leading to an accumulation of dopamine in the synaptic cleft. This is what causes the pleasurable feeling that cocaine users experience. Over time this increased dopamine level downregulates the number of postsynaptic receptors, meaning that more of the drug is needed to get the same experience. For this animation with text see K004/0312. | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / Biocosmos / Francis Leroy & Michael Pierard |
Modell-Rechte: | nicht erforderlich |
Länge: | 47 Sekunden |
Seitenverhältnis: | 16:9 |
Restrictions: | - |