Section 2 Martin Flashcards
what are two functions of the nervous system
communication and control
by sensory output
integration
motor output
describe the organisation of the nervous system
there are two main parts, there is the sensory and there is the motor. the motor breaks into somatic and autonmic. with somatic (voluntary and reflex) being for skeletal muscles.
while Autonomic is split into sympathetic (accelerator) and parasympathetic (brakes)
Describe how nerve impulses are transmitted
saltatory conduction, Jumps between them
explain the structure of a neuron
Dendrites to a cell body to a axon to a axon terminal
at the axon terminal is a axon bulb with a synapse.
difference between sympathetic and parasympathetic systems
the sympathetic accelrates while parasympathetics brakes.
one found at the top and bottom of the spine, while the other is all along the back
Four neurotransmitters chemicals
noradrenaline, dopamine, acetylcholine, gaba
describe the electrical components of neurotransmission
both K and Na gate are closed, with Na outside and K on the inside of the cell.
when depolarisation occurs the Na gate opens allowing Na to enter. once repolarised the K gate opens allowing K ions to go outside.
where does the parasympathetic nerves originate from
from the lower brain (top) and sacral region (bottom) of the spinal cord.
where does the sympathetic nerves originate from
the originate from thoracic and lumbar regions of the back (majority of the back )
Four parasympathetic results by releasing …
acetylcholine
Constricts pupil of eye, constricits bronchi in lungs, slows heart, promotes emptying the bladder.
muscarinic receptors ? Neurotransmitter: Agonists : Effects Antagonists
acetylcholine,
muscarine, carbachol,
pilocarpine, bethanecol
CNS excitation
Cardiac inhibition
Gastric/salivary secretion
Vasodilation
Atropine, ipratropium
Nicotinic receptors ? Neurotransmitter: Agonists : Effects Antagonists
acetylcholine
nicotine, carbachol,
succinylcholine
CNS excitation
Skeletal muscle contraction
Secretion of adrenaline
Tubocurarine (curarie)
α-bungarotoxin
fours effects of the noradrenaline on target organs
dilates pupil of eye, relaxes bronchi in lungs, accelerates heart, inhibits emptying the bladder
Beta Receptors Neurotransmitter Agonists Effects Antagonists
Noradrenaline, adrenaline, isoprenaline, clenbuterol, salbutamol Increase heart rate Increase blood pressure Relax smooth muscle (e.g. airways) Vasodilation propranolol
Alpha Receptors Neurotransmitter Agonists Effects Antagonists
Noradrenaline adrenaline, phenylepherine Decongestant Vasoconstriction Reflex bradycardia phentolamine phenoxybenzamine
synpase bulb, inactivation of message by
- re-uptake by nerve (NET)
- Breakdown by MAO (methyl aluminoxane) enzyme or uptake by vesicles.
- activation of pre-synaptic receptors
names part of the synpase bulb
Sites of intervention
false transmitter depletion of transmitter re-uptake (NET) blocker enzyme inhibitor pre-synpatic receptor agonist or blocker receptor agonist or blocker enzyme inhibitor uptake blocker (ENT)
Amplify or mimic
reuptake blocker - cocaine displaces noradrenaline - amphetamine MAO inhibtor - phenelzine Uptake Blocker - corticosterone postsynaptic receptor agonist- clenbuterol
peyote cactus drug
mescaline
psilocybe mexicane drug
psilocybin
christmas vine drug
ergoline
Ayahuasca drug
DMT- Dimethyltryptamine
Tabernanthe iboga
Ibogaine
fly agaric
muscimol
Ergot fungus on rye
LSD, discovered by Hoffman
Diviners Sage Drug
Salvia, affects only 2 receptors, non toxic, very potent
what are hallucinogens
chemicals that cause alterations in mental state, leading to perturbation and distortions in sensory perceptions, thinking and mood
Four Psychological effects of hallucinogens
Mood changes, memory loss/ confusion, dissociative effects. states of ecstasy
Four physical effects of hallucinogens
increased tmeperature, dilation of pupils, dryness of the mouth, sweating
MOA of hallucinogens
indole hallucinogens mimic the neurotransmitter serotonin in the CNS
target of hallucinogens
5-HT receptors, which bind the ligand serotonin (5-HT)
these drugs can mimic serotonin.
number of 5-HT receptors and the important one
7 types, focus is 2.
2A which blocks LSD and psilocybin
in CNS predominantly the frontal lobes
most hallucinogens are 5HT 2A agonists
how do hallucinogens affect the prefrontal cortex
they increase glutamate release in the PFC,
leads to intermittent bursts of neuron firing
important parts of the brain for hallucinogens
thalamus, amygdala, prefrontal cortex
magic mushroosm MOA
it is a GABA receptor agonists
the role of hormones in the nervous and endocrine system
communication and control is the role of hormones
for the nervous system: rapid short acting
while for endocrine system: slow long acting
Chemical properties of different hormones and why
peptides, steroid and amines are all types of hormones. have different properties and therefore have different uses
peptides
are 1000 to 100000, water soluble, orally inactive, not heat stable, natural example is insulin and synthetic is recombinant insulin. administered by injections
steroids
are 360 in size, arent water soluble, maybe orally active, are heat stable, natural example is cortisol, synthetic example is prednisone and administered by injection, cream or implant
Amines
are 200 in size, maybe water soluble, maybe orally active and heat stable, natural examine is adrenaline, synthetic is clenbuterol. administered by injection, pill, and inhaler.
Cortisol is..
the stress hormone, it is a steroid that is secreted by the adrenal gland, generates glucose, suppresses immune system
what is cortisol stimualted and lowered by
stimulated by excitement, fear, anxiety, trauma
while lowered by rest, massage, music, dancing
how cortisol is produced and reacted (the long image thing)
external or internal stimuli causes the hypothalamus to produce CRF and causes the pituitary to produce ACTH which in turns causes the adrenal gland to produce cortisol. this then is deposited into the tissues. this can have a negative feedback decreasing the amount produced.
more moa of cortisol
coritosl, enters the cell, binds to the receptor, enter nucleus, binds to DNA and causes new proteins to be made
useful effects of cortisol
mobilises glucose, creates memories, mobilises calium and protein and improves mood.
Cushing’s Syndrome is caused by what and its effects
causes by too much cortisol and causes red cheeks, thin skin, hypertension and abdominal fat
glucose MOA in the body
the digestive system breaks down food adn takes the glucose and takes to the pancreas which turns it into insulin which is then deposited into adipose tissue.
an insulin receptor is found on the cell wall of other tissues and tyrosine kinases controls this
normal MOA of glucose in heathly body
higher sugar diet, produces normal blood glucose. this produces insulin which the GLUT 4 transporters activated in muscle and other tissues and glucose returns to normal.
what is insulin dysregulation
peripheral insulin resistance
gluclose levels increase as normal after a meal, insulin is produced but tissues fail to take up glucose in response to insulin. insulin concentration increase, glucose slowly returns to normal.
result of insulin resistance
to much insulin cuases blood glucose to never return to normal causing increase amount of insulin as pancreas fails and glucose transporters fail. this causes glucose toxicity known as type 2 diabetes.
insulin resistance in horses
causes laminities, insulin toxicity
extreme insulin dysregulation
Blood glucose levels increase beyond normal after a meal Insulin concentrations increase beyond normal (and may cause laminitis) Over time, insulin receptors become downregulated due to high insulin, and insulin resistance occurs, making things worse
four endocrine hormones and their affects and target
oxytocin affects smooth msucle and mammary glands, produced by pituitary
TSH affects thyroid and therefore liver muscles
ACTCh affects adrenal cortex and produces cortisol which affect many tissues
growth hormone affects the liver muscles and bones
major endocrine glands in the body and location
Pineal gland - brain hypothalamus - brain pituitary - brain thyroid glands- throat parathyroid glands - throat pancreases adrenal gland gonads
pineal gland main hormones and action fo hormones
melatonin, control o seasonal fertlity/breeding and sleep/wake cycle
HYPOTHALAMUS main hormones and action fo hormones
releasing factors, growth hormone releasing factor. corticotropin releasing factor. LH releasing factor. control the pituitary gland
PITUITARY main hormones and action fo hormones
porlation, growth hormone, oxytocin, tropic hormones
thyroid glands main hormones and action of hormones
T3 triiodothyronine and T4 thyroxine stimulate metabolic rate
calcitonin lowers blood calcium
parathyroid glands main hormones and action of hormones
parathyroid hormone, increases blood calcium
pancreas main hormones and action fo hormones
insulin and glucagon, control blood sugar levels
adrenal gland main hormones and action fo hormones
adrenaline, noradrenaline, increase heart rate, blood pressure, respiration and mobilise fat.
cortisol, aldosterone, mobilised energy, maintains mineral balance.
gonads main hormones and action of hormones
oestrogen, testosterone, and progesterone control sexual development, reproductive function and growth of bone, muscle and fat
pharamacoviligence is…
‘the science and activities relating to the detection, assessment, understanding
and prevention of adverse effects or any other drug-related problem’
concern of pharmacovigilance
herbs, traditional and complementary medicine, blood products, biologicals, medical devices and vaccines
