Lecture 33 - Orexin Flashcards
Where is the only place hypocretins are being produced?
the hypothalamus
What are the levels of orexin during sleep and when awake?
high during awake
low during sleep
Orexin 1 and oxrexin 2 work on _ receptors (GPCR)
2
Hcrt 1&2
Orexin neurons are active during ___ ___ ___ and silent during,,,
active during active wake state
silent during NREM and REM sleep stages
People suffering from nacrolepsy will have…
oscillating sleep/wake cycles - not the normal ones following the circadian rhythm
OX-a has a ___ bond
cysteine bond
There is a relationship between the lateral hypothalamus and drug dependence (morphine, cocaine) - so _____ _______ can be used as rteatment for addiciton
orexin antagonists
Orexin neurons promote wakefullness thoroguh the _________ _____ that are wake - active. Stimulation of dopaminergic centres by orexins can modulate _____systems
Orexin neurons promote wakefullness thoroguh the monoaminergic nucleui that are wake - active. Stimulation of dopaminergic centres by orexins can modulate reward systems
Peripheral metabolic signals such as leptin, ghrelin and glucose influence orexinnneuronal activity to coordinate …..
Peripheral metabolic signals such as leptin, ghrelin and glucose influence orexinnneuronal activity to coordinate arousal and energy homeostasis
What happens in the sleep state with regard to VLPO monoaminergic neurons in narcoleptic pateints?
nromally: VLPO takes over from the Orexin neurons in stimulating the monoaminergic neurons (which them stimualtes thalamus) - which puts peple to sleep
in narcolepsy: the orexin neurons aren’t there so there is no switch - the signal just goes back and forth between the VLPD neurons and monoaminergic neurons
What does the orexin receptor blockade induce and maintain?
sleep without motor side effects
All 4 Ox1/Ox2 antagonists in development have the same issue being…
REM/NREM imbalance and strange pharmocokinetics
