Sedatives and Hypnotics Flashcards
What is the optimum number of hours for a healthy sleep?
7-9 hours
What are the 2 main types of sleep?
- rapid eye movement (REM)
- non rapid eye movement (NRRM)
How long does each sleep cycle last?
90-120 minutes i.e. in a typical night there are 2-3 cycles
Describe the 4 stages of the sleep cycle
- light transitional sleep - drowsiness
- mores stable sleep - chemicals block senses making it difficult to be woken
- deep sleep - GH released
- revitaliser memory - intense dreams occur
How can human brain activity be measured?
electroencephalogram (EEG)
What happens in stage 1 of NREM?
- hypnagogic and hypnopompic hallucinations
- muscles twitches
- theta waves
What happens in stage 2 of NREM?
- theta waves
- K complexes and sleep spindles
What happens in stages 3 and 4 of NREM?
- delta waves
- night terrors
- deep sleep
- GH released
What happens in REM?
- muscle paralysis
- brainwaves resembling awake state
- dreaming
- nightmares
When does REM duration increase?
towards the ends of the night
What is memory consolidation?
when short-term memory is converted to long-term memory
What can one night of bad sleep cause?
an accumulation of toxic beta amyloid in the brain
Give examples of sleep disorders
- snoring
- obstructive sleep apnoea
- insomnia
What does GABA binding to its receptor cause?
hyperpolarisation
What does the GABA receptor consist of?
19 subunits
Where does GABA bind?
at the interface of the alpha and beta subunits
What are GABA α1 subunits involved in and where are they highly expressed?
sleep expressed in ventrolateral preoptic nucleus
What are GABA α2 and 3 subunits involved in and where are they highly expressed?
anxiety expressed in amygdala
What are sedatives and hypnotics?
a class of drugs used to induce and/or maintain sleep, for example benzodiazepines and non-benzodiazepines (Z-drugs)