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15 Cards in this Set
- Front
- Back
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Wavelength of light needed to make: Seratonin? Vitamin D? What is fluorescent light lacking? What is needed for melatonin production? |
- 480nm - 295nm UVB - lacking wavelength needed for seratonin and Vit D production -Need 480nm light to be absent (light shuts down its production) |
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Two pathways which light acts on the body? What does each do? What is second pathway most sensitive to? |
Primary optic tract: governs visual perception and responses Retinohypothalmic tract: governs circadian, endocrine and neurobehavioural functions. Most sensitive to 459-485nm blue light |
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How does light signalling occur? |
Light signals through melanopsin protein that undergoes a chemical change when exposed to light received by intrinsically photosensitive retinal ganglion cells in the back of the eye |
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Health effects of circadian clock deregulation? (sry idiot) |
Insomnia and sleep disorders, reduced alertness, poor cognitive and motor function, mental problems (depression etc), CV disease, altered hormone levels, obesity, early-onset diabetes, altered immune function, cancer (breast, prostate, colon) |
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Hormones related to breast cancer and the hypothalmus exposure to light? |
GnRH, estrogen, progesterone, melatonin, seratonin, vit D (calcitriol) |
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What secretes melatonin into the blood? What two things are needed for its production? |
Pineal gland. Darkness and low temperature |
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What happens when the SCN is exposed to first light? |
-Begins performing functions like raising body temperature and releasing hormones like cortisol |
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What is seratonin? Where is it produced? Major action on many antidepressants? When are levels the highest? Derived from? |
-neurotransmitter, which functions as a hormone in the CNS to regulate mood, appetite, memory and sleep -most is produced in gut, rest in CNS -modulation of seratonin levels -in afternoon: need 480nm light, derived from tryptophan (found in protein-based food) |
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Synthesis pathway of melatonin from tryptophan? Rate limiting step (bold)? |
Tryptophan -(tryptophan 5-hydroxylase)- 5 hydroxytryptophan -(5 HTP-decarboxylase)- 5 hydroxytryptamine/Seratonin -(seratonin N acetyltransferase)- N acetylseratonin -(HIOMT)- Melatonin/N acetyl 5 hydroxytryptamine |
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Relationship between breast cancer, melatonin, seratonin, vit D and light? |
-Periodic or circadian sunlight exposure during the day controls levels of seratonin, melatonin and Vit D - Breast cancer associated with low levels of melatonin, seratonin and vit D -changes in levels of these hormones as well as temperature are biomarkers of the circadian clock |
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What parts of everyday life are associated with breast cancer? What are endocrine disrupting chemicals? What do disruption of biological rhythms do? |
-Various genetic, dietary, behavioral and environmental conditions - chemicals in our environment that disrupt our hormones and increase risk of chronic diseases like cancer -alters our hormones and increases risk of chronic diseases like cancer |
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Major disruption to our environment? |
Built indoor environment, which alters exposure to natural sunlight and darkness and exposes us to artificial lighting. Also effected by geographical location and population differences |
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What does exposure to environmental light alter the metabolism of? Also alters? What do these changes do? |
Key hormones including GnRH, estrogenm progesterone, testosterone, vit D and melatonin. Also alters NTs (dopamine and seratonin) as well as micronutrients including iron. -increase risk for chronic disease including breat cancer |
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What else are low serotonin levels tied to? Thus? |
Commonly found in depression and people with seasonal affective disorder (SAD), which is problematic in Western world. -thus mass prescription on SSRIs: these patients have a reduced breast cancer risk |
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How else could serotonin be tied to breast cancer? How could Vit D be involved in this? |
-It is a part of the melatonin synthesis pathway by the pineal gland: low serotonin = low melatonin -Vit D activates transcription of serotonin synthesizing gene: tryptophan hydroxylase -melatonin and Vit D downregulate estrogen |
