Evidence for plasticity of the dopaminergic system in parkinsonism.

摘要: A series of compensatory mechanisms within the dopaminergic system have been shown to maintain clinical function in presence dopamine loss. Experimental evidence for increased presynaptic turnover owing synthesis, release, and reduced reuptake exists. Direct that these extracellular levels is provided by intracerebral microdialysis techniques. Postsynaptic denervation supersensitivity clearly occurs with D2 receptors, although this less evident D1 receptors. Similarly, plasticity be relevant human postmortem Positron Emission Tomographic studies patients Parkinson's disease. However, increases are well documented, postsynaptic receptor changes more difficult establish, mainly because methodological difficulties. but not D1, documented drug naive Parkinsonian PET In transplantation adrenal gland striatum animal models Parkinsonism where improvement occurs, host response may as important graft. Although some elements mechanism deleterious, such dyskinesias supersensitivity, overall effect delay minimization expression disease advantageous. An even greater understanding involved assist developing future therapeutic strategies.