B6 W2 Flashcards
Effect of M1, M3 and M5
Excitatory response which is coupled to Gs protein. It activates phospholipase C and elevates IP3 levels for Ca2+ release.
Vesamicol
Drug inhibiting ACh carriers for ACH vesicle formation
Types of noradrenaline transport systems
Neuronal, extraneuronal and vesicular systems
MAO metabolises…
serotonin and noradrenaline
Substrates of the vesicular noradrenaline transport system
Dopamine, serotonin, guanethidine and MPP
Risperidone
Second gen anti-psychotic which has higher affinity for D2, A1 adrenergic and serotonin 5-HT2a. Reduced affinity for D1, H1 (histamine) and no affinity for muscarinic ACH receptors.
Risperidone increased affinity for….
D2, A1 adrenergic and serotonin 5-HT2a receptor
Risperidone has a decreased affinity for…
D1, H1 and mACH receptors
Tubocurarine
Non-depolarising nicotinic blocking agent. It is a Competitive antagonist for nicotinic postsynaptic receptor.
Craniosacral outflow
Cranial nerve 3, 7, 9, 10 and S2, S3 and S4
Tetanus
Infection with causes prolonged muscle contraction via inhibition of the Renshaw cells
Adenyl cyclase inhibition
Gi proteins coupled to open K+ conductance ion channels by A1, M2 and M4
Receptors between splanchnic nerve and chromaffin cells of the adrenal medulla
Nicotinic acetylcholine receptors
Neurons of the autonomic pathway
Pre-ganglionic- myelinated B fibre with soma is in the brain or spinal cord
Post ganglionic- unmyelinated C fibre with soma in sympathetic ganglia
Tuberoinfundibular
Dopamine pathway from the hypothalamus arcuate nucleus to stimulate D2 receptors in the anterior pituitary to release prolactin
Insight learning
Rapid restructuring of an idea when learning the relationship between means and end
A2 adrenergic receptors
Decreased cAMP, Ca2+ channels and K+ channels
Anti-depressants
Tricyclics, SSRIS, SNRIs and MAO inhibitors
Muscarinic receptor which enhances locomotion
M4- found in the CNS. Coupled to Gi to decrease cAMP and protein kinase signalling
Hemicholinium
Inhibits choline reuptake into presynaptic cell via choline carrier
Atracurium
Intermediate postsynaptic nicotinic inhibitor
Substrates in the extraneuronal noradrenaline transport system
Noradrenaline, dopamine, serotonin and histamine
Positive reinforcement dependent on the number of responses
Ratio reinforcement
Gq protein
Causes formation of phospholipase C to increase intracellular Ca2+ via M1, M3 and M5 action
Nigrostriatal pathway- side effects of inhibition
Irreversible effects by anti-psychotic drugs is Parkinsonism, akathisia, acute dystonia and tardive dyskinesia
Hyperventilation
Decreased pCO2 and causes respiratory alkalosis. Blood Ca2+ decreases, reduced Na channel membrane interaction causing vasoconstriction and paraesthesia. May lead to tetanus.
M1 receptor
Found in the autonomic ganglia, salivary and lacrimal glands and cerebral cortex. CNS excitation and gastric secretion by increasing K+ conductance
Botulinum
Inhibits exocytosis of vesicles of neurotransmitter
White rami communicantes
Carry myelinated preganglionic axons to the sympathetic chain
Social learning
Process of altering behaviour by observing and imitating the behaviour
Post ganglionic neurons in the autonomic nervous system
Unmyelinated type C
Removal of an adversive stimuli adter desired behaviour has occurred
Negative reinforcement
Non-depolarising blocking agent
Drugs which prevent acetylcholine reuptake into the presynaptic cell or bind to the post synaptic cell and prevent acetylcholine binding
Resperine and tetrabenazine
Inhibitors in the vesicular noradrenaline transport system
Clozapines
Anti-psychotic which is used as an alternative. Targets serotenergic receptors more than dopaminergc. Adverse side effect is agranulocytosis.
Splanchnic nerves
Conveys information about nutrient content of the stomach to the brain
Organophosphate poisoning
Chemical stabilisation and forms irreversible phosphate bond with active site of acetlycholinesterase through aging process. This allows acetylcholine to accumulate and cause paralysis
Avoidance learning
Negative reinforcement which provides escape from unpleasant situation by removal of stimulus
Thoracolumbar outflow of the sympathetic nervous system
T1-L2.
Type of learning causes the origin of certain phobias
Classical conditioning
Substrates of the neuronal noradrenaline transport system
Tyramine, methylnoradrenaline, adrenergic, ampehetamine
Which dopaminergic system are antipsychotics used to target?
Mesolimbic
M2 and M4
Coupled to Gi protein to decrease cAMP and decreases protein kinase A
Cocaine
Inhibits noradrenaline transport. Mimics noradrenaline and histamine but is not an antidepressant. It cause increases dopamine levels
Tricyclic antidepressant
Increases availability of catecholeamines and serotonin. Inhibits noradrenaline transport system.
Phenoxybenzamine
Alpha adrenoreceptor antagonist used to treat pheochromocytoma It inhibits noradrenaline transport system and extraneuronal trasnport
Amphetamine
Inhibits noradrenaline transport system, increases dopamine levels and mimics noradreanline and serotonin but does not act as an antidepressant
Resperine
It reduces dopmaine transmission and has antipsychotic effect by reducing MOA entering vesicles. Inhibitors in the vesicular noradrenaline transport system.
Autoreceptors
Causes reuptake of extra serotonin when taking anti-depressants. These receptors desensitise.
M3 receptors
Coupled to Gs protein which increases cAMP. Found in the exocrine glands, blood vessel endothelium, GI tract. Causes GI smooth muscle contraction and gastric/salivary secretion
Extraneuronal transport
Adrenaline > noradrenaline > isoprenaline
Substrates dopamine, serotonin and histamine are taken up
Inhibition of extraneuornal transport of noradrenaline
Steroid hormone and phenoxybenzamine
Paravertebral ganglia
Interconnected ganglia close to the spinal nerves and the vertebrae
Least splanchnic nerve
T12 level that provides sympathetic innervation to the abdomen
Tyramine
Indirectly acting sympathomimetic which causes NET exchange with noradrenaline found in marmite, cheese and wine
Unmyelinated type C fibres
Post ganglionic neuron
Detrusor muscle
Smooth muscle of bladder
Olanzapine
Second gen antipsychotic
Arguments against dopamine hypothesis
Glutamate induced excitotoxicity may cause neurodegeneration of schizophrenia.
Environmental influence such as upstream factors may influence this.
Antipsychotics have an immediate effect on the dopamine neurotransmitter levels but it takes 2 weeks to work.
Other neurotransmitters may be invovled such as serotonin and histamine.
Benzodiazepine- side effects
Impaired motor control, confusion and respiratory depression
Three main types of phobia
Agoraphobia, social phobia and specific phobia
Sympathetic nervous system
Preganglionic neurons are short and postganglionic neurons are long
Conditioned response
Learned response to stimuli which did not originally occur
T10-T11
Sympathetic innervation of midgut by lesser splanchnic nerve
SSRI side effect
Nausea, sexual dysfunction and drug metabolism inhibition
Tricyclic
Antagonises histamine, muscarinic, and alpha adrenoreceptors. Potential sthe effect of alcohol and anaesthetics. Causes sedation, dry mouth and postural hypotension.
Side effects of antipsychotic drugs
Weight gain, diabetes, raised cholesterol
Behavioural therapy
Encourages people to stop doing activities which maintain the problem and start going to activities they previously enjoyed
Outflow of parasympathetic system
Cranialsacral outflow
Motor information carried to the skeletal muscle
Somatic nervous system- single lower motor neuron, using acetylcholine neurotransmitter and is excitatory
Innervation of foregut at Levels T5-T9
Greater splanchnic nerve
Cognitivie therapy
Challenges way of thinking and encourages healthier self-talk
Noradrenaline transport system
Equal specificity with noradrenaline, adrenaline and isoprenaline. Transports dopamine, 5-hydroxytryptamine (serotonin) and guanethidine. Inhibited by reserpine and tetrabenazine
Noradrenaline transport system substrates
Includes Dopamine, serotonin and guanethidine.
Noradrenaline transport system inhibitors
Resperine and tetrabenazine
M2
Found in heart atria. Coupled to Gi protein to decrease cAMP. Response of cardiac inhibition and neural inhibition
Argument for dopamine hypothesis
Antipsychotics block dopamine. Reserpine is
a treatment which reduces dopamine transmission and has an antipsychotic effect by reducing MOA entering vesicles. High dopamine is caused by cocaine, amphetamine and L-DOPA with dementia medication.
How can we view dopamine activitiy in the brain?
PET and SPECT scans
Nitroxidergic post ganglionic neurons
Release NO in the blood vessels for vasodilation
Tuberoinfundibular pathway contributes to schizophrenia via…
Increases negative symptoms. Treatment will increase dopamine transmission
Negative symtoms of schizophrenia
Mesocortical and tuberoinfundibular
Nucleus accumbens
Located in the basal forebrain, forming most of the ventral striata. It is the interface between motivation and action
Positive symptoms
Mesolimbic causes hallucinations and delusions
Mesolimbic pathway
Transmits dopamine from midbrain ventral tegmental area to ventral striata. Includes the nucleus accumbens for motivation and emotion. Hyperactivity causes positive symptoms of schizophrenia.
Tuberoinfundibular pathway hypoactivity of doapmine
Caused typically by schizphrenia negative symptoms and antipsychotic drugs. Leads to amenorrhoea, galactorrhoea and sexual dysfunction and breast enlargement
Tuberoinfundibular pathway hyperactivity of dopamine
Osteoporosis
Mesocortical pathway
Dopamine is released from the midbrain via the ventral tegmental area to the prefrontal cortex. Hypoactivity of this is responsible for the negative symtposm of schizophrenia
Nigrostriatal pathway
Transmits dopamine from the substantia nigra pars compacta to the caudate nucleus and putamen.
How do antipsychotics affect the nigrostriatal pathway?
Blocks dopamine and leads to tardive dyskinesia ( sudden irregular movement like waving hands or sticking out tongue) , akithisia (restlessness) and dystonia (muscle contraction) and Parkinsonism
What is Parkinsonism?
Brain conditions which cause TRAP- causes include side effects of medication, like antipsychotics and the degeneration of cells leading to Parkinson’s.
Causes of schizophrenia
Damage to the hippocampus and hypothalamus from auto-antibodies, neurodevelopmental caused by disruption of brain development perhaps by drugs, high dopamine or glutamate levels and psychological cause.
Nervous supply to blood vessels
Sympathetic nervous system
Parasympathetic control of the bladder
Excites the dome of the bladder
Sympathetic control of the bladder
Inhibits the dome and excites the neck of the bladder
inc inhibitor
Adrenergic receptors increasing cAMP
B1, B2 and B3 receptors
Grey rami communicantes
Contains unmyelinated post ganglionic axons of the sympathetic chain
Myenteric plexus
Plexus of nerves of sympathetic and parasympathetic system between the two laters of muscle in the small intestine.
Enteric nervous system
Division of the autonomic nervous system. controls peristalsis and gastrointestinal secretion. Contains myenteric and submucosal plexus.
Noradrenaline transport system
Uses the Noradrenaline transporter (NET) which is Na+/CL- dependent for the movement of nroadrenaline via vesicles, neuronally or extraneuronally.
