synaptic transmission

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presentation icludes information about chemical synaptic transmission, main neurotransmitters in humman body and how can this type of synaptic transmission be influenced with drugs

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By: vg81 (19 month(s) ago)

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Synaptic transmission : 

Synaptic transmission

Types of synaptic connections : 

Types of synaptic connections Chemical Electric Conjoint

Electric synapse : 

Electric synapse Gap junction - Cylinder of 6 connexin subunits Ions just flow through the channel and change the potential of the cell Regulation of the ion flow: c Ca2+, pH, cAMP Connection between: glial cells and neurons rods and cones Advantage: transmission is faster

Chemical synapse : 

Chemical synapse The most common type in humans and vertebratea Adavantages: Polarity Integration Modulation

Chemical synpse : 

Chemical synpse Polarity: The transmission succeds only in one direction Integration: There are lots of synaptic clefts on one neuron and incoming signals are summated before generating the action potential Modulation: The transmission can be influenced by other chemicals in the synaptic cleft

Electric and chemical synapse : 

Electric and chemical synapse

Main neurotransmitters in human body : 

Main neurotransmitters in human body Acetylcholine Catecholamines Dopamine, noradrenaline, adrenaline Serotonine Histamine GABA, glycine – inhibiting Glutamate, aspartate - excitating

Acetylcholine : 

Acetylcholine The parasympathetic nervous system acetylcholinesterase: Brokes the acetylcholine down in the synaptic cleft after binding to the receptor Acetylcholine ? acetate + choline Cholin reuptake to the presynaptic neuron M receptors - G-protein + ion channel N receptors - part of Cl- channel

Acetylcholine : 

Acetylcholine N-receptors heteroreceptors of glutamatergic, hydroxytryptaminergic, GABAergic or dopaminergic neurons Increase of released neurotransmitter learning, memory, motoric functions

Acetylcholinesterase inhibitors : 

Acetylcholinesterase inhibitors Acetylcholine stays longer in the synaptic cleft, works longer They are used to treat Alzheimer´s disease: Physostigmine, rivastigmine, donepezile, galantamine

Atropine : 

Atropine M and N receptors antagonist, is used as active substance in Spasmolytic drugs – cramps of GIT Mydriatic drugs Prevents bardycardia

Catecholamines : 

Catecholamines Adrenaline Noradrenaline Dopamine

Catecholamines : 

Catecholamines Reuptake from synaptic cleft MonoAaminoOxidase-A (MAO-A): breaks down adrenaline and noradrenaline in the neurons MAO-B: breaks down dopamine in extracellular space Cresyl-O-MethylTransferase (COMT)

Dopamine : 

Dopamine Receptors – adenylatcyklase D1+5 - stimulation D2,3,4 - inhibition D2 - motoric functions D3,4 - limbic system D4 - in GABAergic neurons Adrenaline and noradrenaline are agonists

Parkinson´s disease : 

Parkinson´s disease Deficit of dopamine in the neurones of basal ganglia Treatment: COMT inhibitors: tolcapone , entacapone Selective MAO-B inhibitors: selegiline

Adrenaline, Noradrenaline : 

Adrenaline, Noradrenaline The sympathetic nervous system Receptors with G-protein – a, ß Disorders in adrenergic neurotransmission: Narcolepsia Concentration disorders Depression Eating disorders

Adrenaline, Noradrenaline : 

Adrenaline, Noradrenaline Abused drugs: Psychostimulants- noradrenaline, dopamine and hydroxytryptamine synaptic output stimulation Amfetamine, pervitine, MDMA - extasy Antidepressants noradrenaline, dopamine and hydroxytryptamine reuptake inhibitors Inhibitors of MAO

Serotonine(5-hydroxytryptamine) : 

Serotonine(5-hydroxytryptamine) Reuptake from synaptic cleft MAO-A Receptors 5-HydroxyTryptamine1-7 (5-HT), second-messenger systems Activation of the 5-HT receptors hypoactivity (sedation, sleep, depression) agressivity, anxiety, sexuality, eating headache

Histamine : 

Histamine Receptors: G-protein H1: excitating, hypothalamus, PNS H2: inhibiting, Hippocampus, Cortex H3: histamine synthesis and output Heteroreceptors: inhibition of acetylcholine, dopamine, noradrenaline and hydroxytryptamine output Regulation of sleep and vigilance Regulation of Eating and water uptake

Antipsychotics : 

Antipsychotics H1-antihistaminergic side effects: Somnolence Increase of body weight

Antihistaminics : 

Antihistaminics H1: prevention of alergic reactions, sedatives, antiemetics, antivertiginous H2: inhibition of gastric HCl secretion H3: experimental research

?-Amino Butyric Acid : 

?-Amino Butyric Acid Main inhibiting neurotransmitter in vertebratea Reuptake from synaptic cleft GABA A receptor part of receptor for: alcohol, benzodiazepines, barbiturates regulation of Cl- channel GABAB receptor – G-protein, inhibition of other neurotransmitters output

Glycin : 

Glycin Inhibiting neurotransmitter Reuptake from synaptic cleft Receptors- Cl- channels Strychnin – agonist - cramps

Glutamate, Aspartate : 

Glutamate, Aspartate Ionotropic receptors: Na+, Ca2+, K+ channels NMDA AMPA kainate Metabotropic receptors: G-protein mGLUR 1-8 Memory functions

Glutamate, Aspartate : 

Glutamate, Aspartate Antiepileptics Topiramate: AMPA inhibitor General anestetics Ketamine: NMDA antagonist