t- caffeine Flashcards
what was the first caffeine containing soda
coca-cola
- sourced from Kola nut
allowed around 71mg (Jolt Cola)
energy drinks
advertise as low caffeine but add other stimulants
ex. milk thistle, ginseng, green tea, St Johns wort
GRAS
generally regarded as safe
absorption- orally
bases- when dissolved in acid highly lipid soluble (low pKa)
absorpbed in digestive tract when taken orally
absorption- medical reasons
given as a salt- more readily dissolves
ex. aminophylline is used for asthma (dilate bronch)
distribution
reaches all organs at varying speeds
stomach, kidney, liver, lung, brain, skeletal muscle
crosses the bbb
elimination
1% excreted 99% metabolized in liver by cytochrome p450 into paraxanthine, theobromine and theophylline\
peak at 6-8 hours
genetics on caffeine metabolism
CYP1A2*1A is rapid caffeine metabolizing
CYPA2*1F is slow caffeine metabolizing
factors that affect CYP1A2 enzyme
slow- alcohol and grapefruit juice
speed up- broccoli
hormones
newborns metabolism
immature liver and CYP1A2 enzyme
excrete around 85% of caffine
half life up to 100 hours
develops around 7-9 months
non-human species
uses different enzymes, different metabolites, different half lifes
neuropharmacology of methylxanthine
caffeine- adenosine receptor blocker - A1 and A2
metabolites- adenosine receptor inhibitor
normally inhibit Ach GABA, glutamate, NE, 5HT and DA
concentrated in dorsal striatum and NA
rewarding effects of caffeine
through interacting with adenosoine caffine impacts functioning of NT systems modulates levels of DA (ventral stiatum) results in enhanced release of DA
receptor mosaic
2 or more receptors are attached to eachother and influence anothers operation
headaches
caffeine dilates cerebral blood vessels and can alleviate headache pain
abstininece syndrome
withdrawl condition of caffeine marked by fatigue anxiety and headache
related to dilation of BV and enhanced inhibitory actions of adenosine on release of transmitter
subjective effects
negative- anxiety, tension, nerves
positive- well being, energy, motivation and confidence
more likely to see positive in non caffeine users and at low doses
taurine and glucose
taurine- counteract stimulatory impact on mood
reduce caffeine withdrawal
glucose- counteract effect of caffeine on hostility and increase tension
increase sustained memory and attneion
cognitive performance
subjectively feel they did better but actullay did not
for regular coffee users may be return-to-baseline rather than enhancement
caffeine on sleep
can produce insomnia and impact regular sleeping patterns (reduces REM which impacts memory consolidation)
ventrolateral preoptic nucleus (VLPO)
sleep inducing center
building of adenosine triggers the sleep center
caffeine blocks this activation by blocking adenosine receptors and keeps you awake longer
cardiac disease
conflicting results- not always measured properly , preperation, genetics (slow metabolizing gene shows CV)
adverse consequences of energy drinks/shots
large consumption can be medically hazardous
can be consumed quickly- not hot or carbonated
dont have to state caffine if naturally occuring or not added
lethal effects
on its own caffine is not easy to overdose
combined with alcohol or drugs it can be dangerous
taurine- increases BP and cardiac muscle contractions
