Hormones

Question 1

what does GH do

Answer 1

increase lipolysis, anabolism, bone and cartilage growth

Question 2

what does thyroid hormone do

Answer 2

increases sodium and potassium pump
increases b adrenorecptors
increases glucose uptake, utilisation, gluconeogenesis, ffa oxidation, anabolism, Co and HR

Question 3

what are the actions of insulin

Answer 3

increases protein synthesis

iincreases glycogenesis, lipogenesis, glut 4 on membrane

Question 4

what are the functions of cortisol

Answer 4

proteolysis, lipolysis, gluconeogenesis,

decreases T cell growth factors, mononuclear cells, cytokines, IgG

negative feedback on CFR and ACTH

reduced vasodilation and fluid exudation

decreases osteoblasts and increases osteoclasts

Question 5

where is corticotropin releasing hormone released from

Answer 5

The paraventricular nucleus (PVN) of the hypothalamus

Question 6

what are the features of an adrenal crisis

Answer 6

hypotension, vomiting, loss of consciousness

Question 7

what drug do you use for benzo overdose

Answer 7

flumazenil

Question 8

where is the taste area in the cortex

Answer 8

most inferior portion of the post central gyrus to the insula

also has a limbic component via the thalamus (vomiting, salivation)

Question 9

describe activation of the odorant receptor

Answer 9

amplifies the initial stimulus

molecule binds to the receptor of the primary olfactory neurone

the receptor activates a G protein which stimulates adenyl cyclase to convert ATP to AMP

camp activates a cation channel making it permeable to Na and Ca

action potential frequency is proportional to log concentration of odorant

Question 10

what is the medial olfactory pathway

Answer 10

ancient

limbic system- emotion and memory

Question 11

what is the lateral olfactory pathway

Answer 11

less ancient- pyriform and prepyriform cortex in the temporal lobe

likes and dislikes and brainstem reactions
does not go to thalamus

Question 12

what is the recent olfactory pathway

Answer 12

passes through the thalamus and orbitofrontal cortex

involved in conscious discernment of odour

Question 13

what is the function of the piriform cortex

Answer 13

lateral olfactory pathway (less ancient)

likes and dislikes

Question 14

where is endolymph found

Answer 14

scala media, semicircular canals, vestibule

Question 15

where is perilymph found

Answer 15

scala vestibuli, scala tympani

Question 16

describe signal detection in the organ of corti

Answer 16

upward deflection of the basilar membrane moves the inner and outer hair cells laterally

most cochlear nerve endings end on the inner hair cells

Question 17

describe cochlear tuning

Answer 17

outer hair cells are stimulated to depolarise, this causes them to contract

this enhances the auditory signal at the centre of the standing wave and inhibits on either side

under olivocochlear control

Question 18

where are the dorsal and ventral cochlear nuclei found

Answer 18

upper medulla

Question 19

where do first order vestibulocochlear neurones synapse

Answer 19

upper medulla dorsal and ventral cohclear nucleus

Question 20

what is the pathway of signals from the ear

Answer 20

dorsal and ventral cochlear nucleus in the upper medulla where first order synapses

some signals travel ipsilaterally but most are contralateral to the inferior colliculus where most fibres synapse

the pathways then project to the medial geniculate nucleus of the thalamus where the fibres synapse

they then join the auditory radiation to the auditory cortex

also goes to reticulum and vermis

Question 21

what is lesioned in Kluver bucy

Answer 21

bilateral temporal lobe

Question 22

what is the reward system

Answer 22

mesolimbic dopamine system

ventral tegmental area of the midbrain, medial prefrontal cortex

Question 23

what is fluoxeting

Answer 23

ssri

prozac

Question 24

what are the functions of the limbic system

Answer 24

emotions and drives via amygdala
homeostasis and motivation via hypothalamus
olfaction via olfactory cortex
memory via hippocampus

Question 25

what is the moa of glucocorticoids

Answer 25

bind to intracellular receptors, migrate to the nucleus and regulate gene transcription

also signalling systems in the cytosol

mediated by camp dependant protein kinase

Question 26

what are the side effects of systemic use of glucocorticoids

Answer 26

opportunistic infecions 
oral fungal/ yeast
wound healing impaired 
osteoporosis
Cns effects

Question 27

what enzyme is missing in CAH

Answer 27

C-21

Question 28

describe the intersection of autoimmunity and diabetes

Answer 28

1st stage- insulitis- T lymphocyte invasion of pancreatic islets

2nd stage- overt diabetes. massive death of islet B Cells

B reactive t cells meet antigen in pancreatic lymph node

PLN is where tolerance to pancreas is first broken down