LECTURE 19 3-9-15-Classes of Neurotransmitters (cont.)2. Peptide TransmittersNeuropeptidesMost are assembled with ribosomesPackaged by Golgi bodiesTransported by microtubulesRelatively slow processAct as hormones to reduce stress, relegated eating and drinking and pleasure and pain, learningDo not bind to ion channelsBind to synaptic receptors to influence the structure ad function of the cellOpioids3. Transmitter GasesNitric oxide (NO), Carbon Monoxide (CO)Water-soluble gasesNot stored in vesiclesSynthesized in the cell when neededDiffuse quickly out of the cellActivate metabolic processes in cellsFacilitate in the production of other neurotransmittersNO controls the muscles in the intestinal walls and dilates blood vessels in active brain regionsIt also dilates blood vessels in sex organsViagra- enhances the chemical pathways influenced by NO-Classes of ReceptorsIonotropic Receptors- embedded membrane protein that acts as (1) a binding site for a neurotransmitter and (2) a pore (or gate) that regulates ion flow to directly and rapidly change membrane voltageOpen or close poreVery rapidNa+, K+, Ca2+Metabotropic Receptor- Embedded membrane protein, with a binding site for a neurotransmitter but no pore. They are linked to a G protein that can affect other receptors or act with second messengers to affect other cellular processesG protein- alpha, beta, gammaAlpha detaches and floats off to bind to an enzymeSecondary messengerPage 156, Figure 5-15-Neurotransmitters in SNS (Somatic Nervous System)Motor neurons in the brain and spinal cord have axons that reach the body’s skeletal muscles, making behavior possibleMotor Neurons- Cholinergic NeuronsAcetylcholine (Ach)Ionotropic receptors-Neurotransmitters in ANS (Autonomic Nervous System)Two systems:1. Sympathetic (fight-flight) and 2. Parasympathetic (rest-digest)Both are controlled by Ach neurons coming from the CNSSympathetic- Norepinephrine (NE) receptorsHeart- excitatoryGut- inhibitoryParasympathetic- Acetylcholine (Ach)Heart- inhibitoryGut- excitatory-CNS has 4 Activating SystemsSmall-molecule transmitters1. Cholinergic SystemMaintaining attentionWakefulnessMemoryDeath of cholinergic neurons and decrease in Ach in the neocortex are thought to be related to Alzheimer’s diseaseDopaminergic SystemMaintaining normal motor behaviorCoordinating motor behaviorLoss of DA is related to muscle rigidity in Parkinson’s diseaseReward and pleasureDrugsToo much DA is thought to be related to schizophreniaNoradrenergic SystemMaintaining emotionsDecrease in NE activity- depressionIncrease in NE activity- maniaSerotonergic SystemMaintaining wakefulnessDepressionOCDPSYC 260 1st EditionLecture 19Outline of Last LectureI. Types of SynapsesII. Types of MessagesIII. Identifying NeurotransmittersIV. Classes of NeurotransmittersOutline of Current LectureI. Classes of Neurotransmitters (Cont.)II. Classes of ReceptorsIII. Neurotransmitters of the SNSIV. Neurotransmitters in ANSV. CNS has 4 Activating SystemsCurrent Lecture LECTURE 19 3-9-15 -Classes of Neurotransmitters (cont.)- 2. Peptide Transmitterso Neuropeptideso Most are assembled with ribosomeso Packaged by Golgi bodieso Transported by microtubules Relatively slow processo Act as hormones to reduce stress, relegated eating and drinking and pleasure and pain, learningo Do not bind to ion channels Bind to synaptic receptors to influence the structure ad function of the cell Opioids - 3. Transmitter Gaseso Nitric oxide (NO), Carbon Monoxide (CO)o Water-soluble gaseso Not stored in vesicleso Synthesized in the cell when neededo Diffuse quickly out of the cello Activate metabolic processes in cellso Facilitate in the production of other neurotransmitterso NO controls the muscles in the intestinal walls and dilates blood vessels in active brain regionso It also dilates blood vessels in sex organs Viagra- enhances the chemical pathways influenced by NO -Classes of Receptors- Ionotropic Receptors- embedded membrane protein that acts as (1) a binding site for a neurotransmitter and (2) a pore (or gate) that regulates ion flow to directly and rapidly change membrane voltageo Open or close poreo Very rapido Na+, K+, Ca2+ - Metabotropic Receptor- Embedded membrane protein, with a binding site for a neurotransmitter but no pore. They are linked to a G protein that can affect other receptors or act with second messengers to affect other cellular processeso G protein- alpha, beta, gammao Alpha detaches and floats off to bind to an enzymeo Secondary messenger o Page 156, Figure 5-15 -Neurotransmitters in SNS (Somatic Nervous System)- Motor neurons in the brain and spinal cord have axons that reach the body’s skeletalmuscles, making behavior possible- Motor Neurons- Cholinergic Neuronso Acetylcholine (Ach)- Ionotropic receptors-Neurotransmitters in ANS (Autonomic Nervous System)- Two systems:o 1. Sympathetic (fight-flight) and 2. Parasympathetic (rest-digest)o Both are controlled by Ach neurons coming from the CNSo Sympathetic- Norepinephrine (NE) receptors Heart- excitatory Gut- inhibitoryo Parasympathetic- Acetylcholine (Ach) Heart- inhibitory Gut- excitatory -CNS has 4 Activating Systems- Small-molecule transmitterso 1. Cholinergic System Maintaining attention Wakefulness Memory Death of cholinergic neurons and decrease in Ach in the neocortex are thought to be related to Alzheimer’s disease o Dopaminergic System Maintaining normal motor behavior Coordinating motor behavior Loss of DA is related to muscle rigidity in Parkinson’s disease Reward and pleasure  Drugs Too much DA is thought to be related to schizophreniao Noradrenergic System Maintaining emotions Decrease in NE activity- depression Increase in NE activity- maniao Serotonergic System Maintaining wakefulness Depression