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Flashcards in Hormones Deck (28):
1

what does GH do

increase lipolysis, anabolism, bone and cartilage growth

2

what does thyroid hormone do

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

3

what are the actions of insulin

increases protein synthesis
iincreases glycogenesis, lipogenesis, glut 4 on membrane

4

what are the functions of cortisol

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

5

where is corticotropin releasing hormone released from

The paraventricular nucleus (PVN) of the hypothalamus

6

what are the features of an adrenal crisis

hypotension, vomiting, loss of consciousness

7

what drug do you use for benzo overdose

flumazenil

8

where is the taste area in the cortex

most inferior portion of the post central gyrus to the insula

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

9

describe activation of the odorant receptor

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

10

what is the medial olfactory pathway

ancient

limbic system- emotion and memory

11

what is the lateral olfactory pathway

less ancient- pyriform and prepyriform cortex in the temporal lobe

likes and dislikes and brainstem reactions
does not go to thalamus

12

what is the recent olfactory pathway

passes through the thalamus and orbitofrontal cortex

involved in conscious discernment of odour

13

what is the function of the piriform cortex

lateral olfactory pathway (less ancient)

likes and dislikes

14

where is endolymph found

scala media, semicircular canals, vestibule

15

where is perilymph found

scala vestibuli, scala tympani

16

describe signal detection in the organ of corti

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

most cochlear nerve endings end on the inner hair cells

17

describe cochlear tuning

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

18

where are the dorsal and ventral cochlear nuclei found

upper medulla

19

where do first order vestibulocochlear neurones synapse

upper medulla dorsal and ventral cohclear nucleus

20

what is the pathway of signals from the ear

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

21

what is lesioned in Kluver bucy

bilateral temporal lobe

22

what is the reward system

mesolimbic dopamine system

ventral tegmental area of the midbrain, medial prefrontal cortex

23

what is fluoxeting

ssri

prozac

24

what are the functions of the limbic system

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

25

what is the moa of glucocorticoids

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

also signalling systems in the cytosol

mediated by camp dependant protein kinase

26

what are the side effects of systemic use of glucocorticoids

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

27

what enzyme is missing in CAH

C-21

28

describe the intersection of autoimmunity and diabetes

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