 |
 |
Audrey, Your question "Is it a lack of dopamine in PD or is it the inability to manufacture and distribute dopamine in the brain?" is not at all dumb. How dopamine actually adapts muscle control in the Basil Ganglia is not well understood. The dopamine is produced in the Substantia Nigra (SN), but the SN has axons (output of the neuron) which extend into the Caudate, Putamen and Thalamus of the BG. These axons terminate in a reservoir of neurotransmitter (dopamine in this case) forming a synapse with the receptor on the next neuron. When the neuron fires, neurotransmitter is released across the synapse and stimulates the receptor. The receptor can then either enhance or inhibit the ability of the next neuron to fire. This latter part is not well understood. How does dopamine impact the firing of the next neuron? So if you ingest a dopamine agonist and it bathes all the receptors all the time, what is this really doing? This is a good question to ponder the next time you have insomnia. Phil Gesotti 50/46+