PSYB64H3 Chapter Notes - Chapter 4: Tryptophan Hydroxylase, Aromatic L-Amino Acid Decarboxylase, Tyrosine Hydroxylase
Document Summary
Neurotransmitters: chemical messenger that communicates across a synapse. Neuromodulators: chemical messenger that communicates w/ target cells more distant than synapse by diffusing away from point of release. Neurohoromone: chemical messenger that communicates w/ target cells at great distance, often by traveling through circulation. Meet most or all of preceding criteria specific for neurotransmitters and appear to play vital role in neurotransmission: Acetylcholine (ach): used at neuromuscular junction, in autonomic nervous system and central nervous system. Neurons that use this as major neurotransmitter are referred as cholinergic neurons. Use building blocks: choline obtained from dietary fats, acetyle coenzyme a (acetyl coa) results from metabolic activites of mitochondria. Enzyme choline acetyltransferase (chat: acts on two building blocks (or precursors) = produce acetylcholine, useful marker for identifying cholinergic neurons, only found in neurons that produce ach. Also produces acetylcholinesterase (ache): enzyme that breaks down acetylcholine: choline from breakdown = recaptured by presynaptic neuron and resynthesized into more ach.