Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Widely Found and Studied Neurotransmitters • Glutamate – has excitatory functions • 4 Ascending activating systems are very important – Cholinergic System uses acetylcholine – Adrenergic system uses noradrenalin – Dopaminergic system (actually 2 systems) use dopamine – Serotonergic system uses 5-Ht or serotonin • GABA or gamma-amino butyric acid – has inhibitory functions Acetylcholine • Activate two types of receptors: – Nicotinic receptors– also stimulated by nicotine and inactivated or blocked by curare – Muscarinic receptors– stimulated by muscurine and blocked by atropine and scopolamine – use second messenger Monoamines • Dopamine – up to 6 types of receptors – Tyrosine forms L-dopa – L-dopa synthesized to form dopamine • Norepinephrine – created by synthesis of dopamine • Epinephrine – created from Norepinephrine • Serotonin (5-Ht) – synthesized from tryptophan Peptides • Many types of neuropeptides; two have been extensively studied • Sustance P – constriction and dilation of blood vessels • Opioid types – – Endorphins – enkephalins How Drugs Work in the Brain • They work at the level of the synapse • Agonists • Antagonists Possible Drug Actions at the Synapse • increase or decrease the synthesis or production of neurotransmitters • increase or decrease the ability of the cell to store the chemical in vesicles • increase or decrease the amount of transmitter released by vesicles into the synapse • it can increase the number and length of time a receptor is open by increasing or decreasing the production of enzymes that break down the neurotransmitter • block or enhance the reuptake and reuse of the neurotransmitter • Altering the actions of second messegers