Lecture 2 Flashcards
How do neurons communicate?
Neurons communicate with each other using special junctions called axons, when action potentials reach this a special chemical called neurotransmitter is released and responded to in the postsynaptic neuron via receptors to generate a graded potential.
How is neurotransmitter stored and released? What happens to unused up neurotransmitter?
neurotransmitter is stored in vesicles, when an action potential reaches the axon the neurotransmitter vesicles travels to the synaptic cleft and merges with the membrane, releasing the neurotransmitter into the cleft. Unused neurotransmitter is recycled back into the presynaptic axon.
What are agonist and antagonist drugs?
Drugs that bind to a receptor and trigger a response are direct agonists, indirect agonists enhance release or action of an endogenous neurotransmitter. Drugs which block or suppress agonist mediated responses are known as antagonists. These are both relative to the synapse they act on.
How are Parkinson’s and schizophrenia related?
Parkinson’s disease and schizophrenia are both related to each other in that the effects are due to the same neurotransmitter (dopamine synapse, antagonists trigger parkinson’s symptoms in normal people, agonists trigger schizophrenia in normal people).
What is common in many drugs of abuse?
dopamine is commonly connected to many drugs of abuse.
What does Intracranial self stimulation involve?
Intracranial self-stimulation appears to produce a pleasurable effect in animals (includes humans). It acts by activating dopaminergic pathways including the nucleus accumbens and VTA. If animals do this they will typically go till exhaustion (no satiation) and will brave more than normally braved for things like food, just like addicts.
