BMS 450 Lecture : ANS overview, organization & transmitters, neurotransmitter metabolism, acetylcholine metabolism, catecholamine metabolism, receptor signal transduction, nicotinic receptor, presynaptic receptors, alpha 2 receptors, ANS target organ effects
Document Summary
Many organs are innervated by both the sympathetic ns and parasympathetic ns. Pre-ganglionic neurons originate in the cns, release acetylcholine (ach) Post-ganglionic neurons originate outside the cns, have nicotinic cholinergic (n) receptors. As with pre-ganglionic neurons, parasympathetic post-ganglionic neurons also release ach. Ganglia are found in or near target organs. In general, organized for local regulation of innervated target organs. In general, organized for coordinated activation of all innervated target organs. Also innervates the inner core of the adrenal glands (i. e. adrenal medullae) Released ach stimulates nicotinic receptors on chromaffin cells. Chromaffin cells release epinephrine (epi; aka adrenaline) into the bloodstream. Action potential calcium in neurotransmitter released. Neurotransmitter defuses, taken up by post-synaptic neuron, taken up by pre-synaptic neuron, or degraded in synaptic cleft. Acetyl coa + choline acetylcholine via choline acetylase. Acetylcholine acetic acid + choline via acetylcholinesterase. Tyrosine dopa dopamine norepinephrine epinephrine. Repackaged in vesicles or metabolized by monoamine oxidase (mao)
