### agent:

Nicotine
* Most nicotine affects brains
  - finds in tobacco
* Some nicotine goes to other parts of the body.
* accelerates the body's processing of caffeine.
* acts as a stimulant on the central nervous system
  - vasoconstrictor, a stimulant, and an appetite suppressant
  - directly on the heart to change heart rate and blood pressure
  - in the former manner, e.g., by mimicking a naturally occurring substance in the body
  - like a poison in the bone, inhibiting fusion of the bone
* acts on several neurotransmitters including acetylcholine and dopamine
  - the central and peripheral nervous system
* affects both reward and withdrawal behavior
  - brain wave function
  - mood as well as the heart, lungs, stomach, and nervous system
  - one kind of receptors for acetylcholine
* alters the structure of the nervous system's receptor up-regulation.
* attacks the cerebral blood vessels.
* binds to the nerve cell surface receptors.
* can be a stimulant
  - very effective method of pest control as well
* can be as addictive as illegal drugs, including cocaine
  - powerfully addictive as heroin or cocaine
* causes a narrowing in small blood vessels, making blood flow more difficult
  - surge of a substance called dopamine between certain brain cells
  - addiction
* causes an increase in a person's metabolic rate
  - heart rate and in the rate of breathing
  - arteries to constrict, so smoking reduces the blood supply to the heart
  - blood vessel constriction that prevents the nutrients from getting to the disc
* causes blood vessels to constrict increasing the heart rate and the blood pressure to rise
  - so that less oxygen and nourishment reaches the baby
  - changes in the oviduct that impede progress of the fertilized egg to the uterus
* causes constriction of peripheral blood vessels
  - the blood vessels and prevents optimum muscle health and function
  - dopamine release in the brain
  - irritation to the lining of the blood vessels
  - other changes in the circulatory system, too
  - strong physical dependency
* causes the arteries to dialate, increasing blood supply to the heart
  - blood vessels to narrow, which then affects blood pressure
* causes the heart to beat faster, which then increases blood pressure
  - much faster
  - user to feel good for a very short time
* changes the brain in long-lasting ways.
* chewing gum is available without a doctor's prescription
  - releases small amounts of nicotine into the body
* comes from the tobacco plant and is extremely toxic to insects.
* constricts blood flow and decreases oxygen supply to the heart.
* constricts blood vessels, making it hard for blood to flow to the penis
  - so the disease or phenomenon can be worsened by smoking
  - peripheral blood vessels and therefore can reduce heat loss
* constricts the arteries in the extremities
  - blood vessels, including the tiny capillaries that serve the skin
* contributes to the growth of cancer.
* cuts down on blood flow to the brain and the penis, both necessary for firm erections.
* damages the endothelium, or cells lining the blood vessels.
* decreases circulation to the feet significantly.
* decreases the circulation in both mother and baby and reduces blood oxygen levels
  - effectiveness of divalproex sodium
  - transit time of food in the bowel and decreases the absorption of nutrients
* does enhance attention, finger tapping, and under certain conditions, memory.
* enables the smoker to remain useful and functional during a normal day.
* enhances brain cell activity and improves cognitive function
  - dopaminergic neurotransmission
* enters readily into mothers' milk and has a half-life of close to two hours
  - the users' bloodstream through the oral mucosa and or the gastrointestinal tract
* excites dopaminergic neurons in the midbrain, and although post
  - the vomiting reflex both in the brain and in the nerves of the stomach
* first stimulates the brain, then causes a letdown.
* generates a physical compulsion combined with a mental obsession to use more nicotine.
* gives a person wrinkles and cold hands.
* helps people control their weight.
* improves synaptic respose, and has an effect on the ability to think.
* increases leptin expression in white fat
  - oxygen demand by increasing heart rate and blood pressure
  - the amplitude ofphysiologic tremor
* increases the heart rate and causes a slight increase in blood pressure
  - rate, but it constricts the blood vessels, which reduces circulation
  - liklihood of blood clots
* inhibits the natural weight set-point and artificially lowers the person's weight.
* interferes with blood circulation, necessary to remove waste products from the bloodstream.
* is addictive substances
  - an alkaloid
  - by far the most dehydrating effects
  - habit forming
  - stimulants
* kills insects by interfering with the transmitter substance between nerves and muscles.
* leaves the body quickly, which is why the urge to light up again also returns quickly.
* lowers estrogen levels.
* maintains tobacco addiction.
* meets the key criteria for addiction or dependence used by major medical organizations.
* moves right into the small blood vessels that line the tissues listed above.
* narrows and restricts blood vessels.
* occurs in tobacco leaves and cocaine is extracted from coca plants
  - naturally in the tobacco plant and constituent of tobacco smoke
* passes freely into the breast milk
  - into breast milk
* plays deadly role in infant death.
* primarily effects the central nervous system as a stimulant.
* produces an addiction, or physical dependence
  - different effects on the body simultaneously
  - effects on the head, lungs, stomach, and the nervous system
  - stimulant effects, while large doses produce depressant effects
* promotes narrowing of the blood vessels, which can impede normal circulation.
* raises blood cholesterol levels.
* raises blood pressure and makes the blood clot more easily
  - the risk of stroke
  - pressure, constricts vessels and raises heart rates
* reduces blood flow to the heart
  - the appetite and increases the urge to eat spicy, salty and fried foods
* refers to the residue of nicotine accumulated in smokers' bodies.
* regulates cerebellar granule neurogenesis.
* relaxes the lower esophageal sphincter muscle and allows it to open.
* restricts blood flow needed to deliver oxygen and nourishment to the spine
  - breathing movements of the mother
* results in less blood flow to the fetus because it constricts the blood vessels.
* speeds up the nervous system and heart.
* spikes an increase in dopamine.
* stimulates adrenal hormone secretion, including cortisol.
* stimulates the heart and central nervous system
  - nervous system and makes the heart work harder
* stimulates the production of adhesion molecules
  - the neurostransmitter dopamine
* suppresses appetite, and also soothes and helps with self-assurance.
* tends to calm the nerves.
* tricks the body into believing it needs the drug to survive.
* use bonds to many emotions and daily activities
  - leads to a reduction in muscle tone
* works by regulating the brain's levels of message-carrying chemicals
  - in the brain in ways similar to drugs like heroin and cocaine
  - on the brain and other parts of the nervous system