Sleep Disorders Flashcards
What is the TMN and which transmitter involved in it?
Tuberomamillary nucleus is in the posterior 1/3 of the hypothalamus, contains histamine neurones.
which NTs are involved in arousal/ wakefulness?
5HT, Histamine, acetylcholine, orexin, noradreneline
which NTs induce sleep?
GABA and galanin, melatonin and adenosine
what is c-Fos?
a proto-oncogene involved in cellular events. expression of c-fos mRNA indicates cellular activity. used as a measure of neural activity.
VLPO?
ventrolateral preoptic nucleus. contains sleep activating neurones expresses GABA and galanin. active in NREM. lesion in VLPO = insomnia. Acts on the (inhibits) TMN and locus coerulus.
GABA-a receptor?
regulates a chloride channel. activation of R = influx of cl- which hyperpolarises and inhibits the cell.
What’s the flip flop switch model?
VLPO active = TMN, LC and raphe inactive = asleep
VLPO inactive = TMN, LC and raphe active = awake. orexin stabilises the FF model. no orexin receptors in the VLPO, asymmetric relationship provides stability
Benzodiazepines?
used for insomnia; lorazepam and temazepam. act on GABA-a receptors, facilitate opening of cl- channels. bind to regulatory site on receptor. p.r.n
effect of BZs?
decrease time for sleep onset and increase total sleep time, if previously less than 6 hours. short half life means avoid hangover effect.
Z drugs?
Zolpidem, Zaleplon, Zopliclone, all act at GABA-a R of alpha 1 beta 2 gamma 2. Zopiclone has the strongest hypnotic effect.
Side effects?
most hypnotic drugs decrease REM sleep and tolerance can develop after 1-2 weeks of use. rebound worsening of sleep may occur.
Name some GABA-a R agonists
Muscimol, propofol, pentobarbital. all increase c-fos expression in VLPO
How could you help narcolepsy?
Use sodium Oxybate, metabolite is a GABA-b R agonist!
