circadian rhythms & sleep/wake Flashcards
_____ activity is a commonly studied output of the circadian rhythm
locomotor
free running period is when rhythms are not tied to __ ___ cycle
light-dark
entrainment of the circadian rhythm is brought about by ____
light
light responsive retinal ___ cells transduce light signals necessary for entrainment
ganglion
small sub pop of retinal ganglion cells express opsins ___ and ___
4 & 5
The RGC project out of the eye to the nerve and project to the ___ in hypothalamus
SCN (superchiasmatic nucleus)
The scn is the ___ and gives rise to pineal gland secretion and circadian rhythm
pacemaker
The SCN pathway is
paraventricular nucleus —> intermediolateral cell column —> superior cervical ganglion —> pineal gland —> melatonin release
lesions in the SCN cause ____
arrythmicity
light pulse close to dark cycle causes a
phase delay
clock controlled genes control
biological processes
dimers of two proteins which are a part of the “clock”
BMAL-1 and CLOCK
protein dimer that is present in higher levels in the morning and less as the day goes on
BMAL-1
BMAL-1 and CLOCK are brought into nucleus and then regulate transcription by binding to
E box (in promotor of clock controlled genes)
BMAL-1 and CLOCK upregulate what genes
clock controlled
regulation of clock controlled genes: PER accumulates in cytoplasm during the day but without ___ is broken down; ____ accumulates at night to stabilize PER
CRY; CRY
BMAL1:CLOCK complex upregulates per and cry genes by binding to ___ in promotors for those two genes
E box
when PER:CRY:CK1 complex gets to nucleus it inhibitis its own transcription by binding to and inhibiting the actions of
BMAL1:CLOCK
BMAL1:CLOCK also upregulates rev-erb and retinoid related receptor genes they bind to ____ __ and repress its expression
bmal 1
the SCN forms connections with neurons and the signal is sent to retinal ganglion cells which express ___ and ___; this activates and AMPA/NMDA receptor which activates kinase and ____
glutamate and PACAP; CREB
in the dark a flash of light can activate ____
CREB
periodic bursts of neuronal activity, the result of interactions between thalamic and cortical neurons
sleep spindles
beta waves at high frequency
awake
sleep spindles and increasing freq.
stage II
delta waves and low frequency
stage III and IV
stimulation of the cholinergic neurons in the __ ___ __ triggers a sleeping cat to waken
reticular activating system
the reticular activating system contains circuits that arise from several areas of the ____
brainstem
for non REM states all of these pathways are decreased
reticular act. system, locus coeruleus, raphe nuclei and TMN
TMN controls ____ release
histamine
the ventrolateral preoptic nucleus anterior (VLPO) is activates leads to (lesions lead to insomnia)
sleep
the ___ neurons activate TMN the ___ inhibits the TMN
orexin; VPLO
diurnal animals have more connection ____ then VLPO
SCN
nocturnal animals connect with VLPO rather than SCN which explains what
different times of activity
