question: If hormones are secreted into blood, and blood needs to pump around the body, how does adrenaline act so quickly
comment: Blood travels through the body at roughly 3-4 miles per hour. This is at rest and just an average though. When your body wants to get ready for a fight or flight situation, your heart rate goes up. Typically a drug injected in the arm, at rest speeds, will hit the brain in just a few seconds. This is assuming a healthy average heart rate, roughly 70-85 bpm. A fight or flight response drives the heart rate up to 115-140. The upper bound of which is twice the lower range of resting heart rate. It’s not quite doubling the speed, perhaps, but it’s making it much faster. Adrenaline is produced just above the kidneys in special glands. This is roughly in the middle of your body. With a blood speed, under stress, of up to 6-8 miles per hour, the hormone will reach your heart, muscles, and brain, in less than a second and a half. It takes a negligible amount of time to enter your blood, and once there it’s running around body faster than a jogging person.
passages: Section::::Function.:Chemical messengers.
  
  The two main chemical messengers of the sympathoadrenal system are norepinephrine and epinephrine (also called noradrenaline and adrenaline respectively). These chemicals are created by the adrenal glands after receiving neuronal signals from the sympathetic nervous system. The different physiological effects of these chemicals depend on the particular tissue that it innervates. As part of the sympathoadrenal system, these chemicals act rapidly and dispel quickly as opposed to the longer lasting effect of hormones.
  
  Section::::Stress.
   Section::::Biosynthesis and regulation.:Regulation.
  
  The major physiologic triggers of adrenaline release center upon stresses, such as physical threat, excitement, noise, bright lights, and high or low ambient temperature. All of these stimuli are processed in the central nervous system.
   Adrenaline may be quantified in blood, plasma or serum as a diagnostic aid, to monitor therapeutic administration, or to identify the causative agent in a potential poisoning victim. Endogenous plasma adrenaline concentrations in resting adults are normally less than 10 ng/L, but may increase by 10-fold during exercise and by 50-fold or more during times of stress. Pheochromocytoma patients often have plasma adrenaline levels of 1000–10,000 ng/L. Parenteral administration of adrenaline to acute-care cardiac patients can produce plasma concentrations of 10,000 to 100,000 ng/L.
  
  Section::::Biosynthesis and regulation.
   For noradrenaline to be acted upon by PNMT in the cytosol, it must first be shipped out of granules of the chromaffin cells. This may occur via the catecholamine-H exchanger VMAT1. VMAT1 is also responsible for transporting newly synthesized adrenaline from the cytosol back into chromaffin granules in preparation for release.
   Section::::Physiological effects.:Memory.
   The adrenal medulla is a minor contributor to total circulating catecholamines (-DOPA is at a higher concentration in the plasma), though it contributes over 90% of circulating adrenaline. Little adrenaline is found in other tissues, mostly in scattered chromaffin cells. Following adrenalectomy, adrenaline disappears below the detection limit in the blood stream.
  
  The adrenal glands contribute about 7% of circulating noradrenaline, most of which is a spill over from neurotransmission with little activity as a hormone.
   Epinephrine, also known as adrenaline, is also used commonly to respond to both internal and external changes. One common cause of the release of this hormone is the Fight-or-flight response. When the body encounters an external stimulus that is potentially dangerous, epinephrine is released from the adrenal glands. Epinephrine causes physiological changes in the body, such as constriction of blood vessels, dilation of pupils, increased heart and respiratory rate, and the metabolism of glucose. All of these responses to a single stimuli aid in protecting the individual, whether the decision is made to stay and fight, or run away and avoid danger.
   The terminology is now one of the few differences between the INN and BAN systems of names. Although European health professionals and scientists preferentially use the term "adrenaline", the converse is true among American health professionals and scientists. Nevertheless, even among the latter, receptors for this substance are called "adrenergic receptors" or "adrenoceptors", and pharmaceuticals that mimic its effects are often called "adrenergics". The history of adrenaline and epinephrine is reviewed by Rao [Trends in Endocrinology and Metabolism, 30(6): 331-334, 2019].
  
  Section::::Mechanism of action.
   Studies have also found that recognition memory involving adrenaline depends on a mechanism that depends on β adrenoceptors. Adrenaline does not readily cross the blood–brain barrier, so its effects on memory consolidation are at least partly initiated by β adrenoceptors in the periphery. Studies have found that sotalol, a β adrenoceptor antagonist that also does not readily enter the brain, blocks the enhancing effects of peripherally administered adrenaline on memory. These findings suggest that β adrenoceptors are necessary for adrenaline to have an effect on memory consolidation.
   Adrenaline (novel)
  
  Adrenaline is the first novel written by James Robert Baker (1946–1997), an American author of sharply satirical, predominantly gay-themed transgressional fiction.
  
  Section::::History.
  
  After graduating from UCLA, he began his career as a screenwriter, but became disillusioned and started writing novels instead. After the controversy surrounding publication of his novel, "Tim and Pete", he faced increasing difficulty having his work published.
   BULLET::::- Another hormone found in the direct response from emotion is adrenocorticotropic hormone (ACTH) secreted in response to fearful stimuli. ACTH is secreted by the posterior pituitary in response to fear and plays a role in the facilitation or inhibition of behaviors and actions to follow. In most cases, a high ACTH secretion will lead to the inhibition of actions that would produce the same fearful response that just occurred.
   An "adrenaline junkie" is somebody who engages in sensation-seeking behavior through "the pursuit of novel and intense experiences without regard for physical, social, legal or financial risk". Such activities include extreme and risky sports, substance abuse, unsafe sex, and crime. The term relates to the increase in circulating levels of adrenaline during physiological stress. Such an increase in the circulating concentration of adrenaline is secondary to activation of the sympathetic nerves innervating the adrenal medulla, as it is rapid and not present in animals where the adrenal gland has been removed. Although such stress triggers adrenaline release, it also activates many other responses within the central nervous system reward system which drives behavioral responses, so while the circulating adrenaline concentration is present, it may not drive behavior. Nevertheless, adrenaline infusion alone does increase alertness and has roles in the brain including the augmentation of memory consolidation.
   As a hormone, adrenaline acts on nearly all body tissues. Its actions vary by tissue type and tissue expression of adrenergic receptors. For example, high levels of adrenaline causes smooth muscle relaxation in the airways but causes contraction of the smooth muscle that lines most arterioles.
   The Schachter–Singer two-factor theory or the cognitive labeling theory takes into account both the physiological arousal and the cognitive processes that respond to an emotion-provoking situation. Schachter and Singer's theory states that an emotional state is the product of the physiological arousal and the cognition regarding the state of arousal. Thus, cognition determines how the physical response is labeled; for example, as "anger", "joy", or "fear". In this theory, emotion is seen as a product of the interaction between the state of arousal and how one's thought processes appraise the current situation. The physiological arousal does not provide the label for the emotion; cognition does. For example, if a person is being pursued by a serial killer, the person will likely be sweating and their heart will be racing, which is their physiological state. The person's cognitive label will come from assessing their quickly beating heart and sweat as "fear". Then they will feel the emotion of "fear", but only after it has been established through cognition. The process is: the event (serial killer chasing the person) -- physiological arousal (sweat, heart racing) -- cognitive label (reasoning; "this is fear") -- emotion (fear).
   Section::::Adrenaline as a transmitter.
   The 2 adrenal glands are located on the top of the kidney and have two distinct sections. The outer region called the outer part which is called the adrenal cortex. The adrenal cortex produce the hormones that are essential for life such as Cortisol and Aldosterone. The inner section, or the Adrenal medulla produce hormones that are not essential for life itself but assist the body in its functions, and these would include a hormone such as Adrenaline.
  
  Section::::Adrenal Hormones.:Cortisol.
   One physiological stimulus to adrenaline secretion is exercise. This was first demonstrated using the denervated pupil of a cat as an assay, later confirmed using a biological assay on urine samples. Biochemical methods for measuring catecholamines in plasma were published from 1950 onwards. Although much valuable work has been published using fluorimetric assays to measure total catecholamine concentrations, the method is too non-specific and insensitive to accurately determine the very small quantities of adrenaline in plasma. The development of extraction methods and enzyme-isotope derivate radio-enzymatic assays (REA) transformed the analysis down to a sensitivity of 1 pg for adrenaline. Early REA plasma assays indicated that adrenaline and total catecholamines rise late in exercise, mostly when anaerobic metabolism commences.
   Remembering his and Barger's structure-activity analysis of 1910, Dale wrote in 1953: “Doubtless I ought to have seen that nor-adrenaline might be the main transmitter – that Elliott’s theory might be right in principle and faulty only in this detail. … It is easy, of course, to be wise in the light of facts recently discovered; lacking them I failed to jump to the truth, and I can hardly claim credit for having crawled so near and then stopped short of it.”
   Primarily referred to in the United States as epinephrine and norepinephrine, adrenaline and noradrenaline are catecholamines, water-soluble compounds that have a structure made of a catechol group and an amine group. The adrenal glands are responsible for most of the adrenaline that circulates in the body, but only for a small amount of circulating noradrenaline. These hormones are released by the adrenal medulla, which contains a dense network of blood vessels. Adrenaline and noradrenaline act at adrenoreceptors throughout the body, with effects that include an increase in blood pressure and heart rate. actions of adrenaline and noradrenaline are responsible for the fight or flight response, characterised by a quickening of breathing and heart rate, an increase in blood pressure, and constriction of blood vessels in many parts of the body.
   He had luck in the latter statement. In most amphibian organs including the heart, the concentration of adrenaline far exceeds that of noradrenaline, and adrenaline is indeed the main transmitter. In mammals, however, difficulties arose. In a comprehensive structure-activity study of adrenaline-like compounds, Dale and the chemist George Barger in 1910 pointed out that Elliott's hypothesis assumed a stricter parallelism between the effects of sympathetic nerve impulses and adrenaline than actually existed. For example, sympathetic impulses shared with adrenaline contractile effects in the trigone but not relaxant effects in the fundus of the cat's urinary bladder. In this respect, ″amino-ethanol-catechol″ – noradrenaline – mimicked sympathetic nerves more closely than adrenaline did. The Harvard Medical School physiologist Walter Bradford Cannon, who had popularized the idea of a sympatho-adrenal system preparing the body for fight and flight, and his colleague Arturo Rosenblueth developed an elaborate but ″queer″ theory of two "sympathins", "sympathin E" (excitatory) and "sympathin I" (inhibitory). The Belgian pharmacologist Zénon Bacq as well as Canadian and US-American pharmacologists between 1934 and 1938 suggested that noradrenaline might be the – or at least one – postganglionic sympathetic transmitter. However, nothing definite was brought to light till after the war. In the meantime, Dale created a terminology that since has imprinted the thinking of neuroscientists: that nerve cells should be named after their transmitter, i.e. "cholinergic" if the transmitter was ″a substance like acetylcholine", and "adrenergic" if it was ″some substance like adrenaline″.
   BULLET::::- The autonomic aspect of an emotion provides the ability to react to the emotion. This would be the fight-or-flight response that the body automatically receives from the brain signals.
  
  BULLET::::- Lastly, hormones released facilitate the autonomic response. For example, the autonomic response, which has sent out the fight-or-flight response, would be aided by the release of such chemicals like epinephrine and norepinephrine, both secreted by the adrenal gland, in order to further increase blood flow to aid in muscular rejuvenation of oxygen and nutrients.
  
  Emotion activates several areas of the brain inside the limbic system and varies per emotion:
   Section::::Plot summary.
   The adrenal medulla is the principal site of the conversion of the amino acid tyrosine into the catecholamines; epinephrine, norepinephrine, and dopamine.
  
  Because the ANS, specifically the sympathetic division, exerts direct control over the chromaffin cells the hormone release can occur rather quickly. In response to stressors such as exercise or imminent danger, medullary cells release the catecholamines adrenaline and noradrenaline into the blood. Adrenaline composes about 85% of the released catecholamines, and noradrenaline the other 15%.
   Sex steroids are not the only important influences upon hypothalamic development; in particular, pre-pubertal stress in early life (of rats) determines the capacity of the adult hypothalamus to respond to an acute stressor. Unlike gonadal steroid receptors, glucocorticoid receptors are very widespread throughout the brain; in the paraventricular nucleus, they mediate negative feedback control of CRF synthesis and secretion, but elsewhere their role is not well understood.
  
  Section::::Function.
  
  Section::::Function.:Hormone release.
   Adrenaline (film)
  
  Adrenaline is a 2015 American drama film directed by Joseph Quinn Simpkins and written by Michael Rosander, Alex Chatfield and Joseph Quinn Simpkins. It stars John Schneider, Charlene Amoia, Gregory Alan Williams, Cameron Arnett and Myke Holmes. The film centers around a drag racer who is left paraplegic by a car crash.
  
  Section::::Cast.
  
  BULLET::::- Charlene Amoia as Josie Rigsby
  
  BULLET::::- Gregory Alan Williams as Elijah Benjamin Salisbury
  
  BULLET::::- Jim Cody Williams as Britt Brizzio
  
  BULLET::::- Malaika Washington as Tiffany
  
  BULLET::::- John Schneider as Paul Sharpe
  
  BULLET::::- Irene Santiago as Diane Godwin
  
  BULLET::::- Michael Rosander as Joseph Jenkins
  
presuppositions: Blood pump slowly enough that there should be a delay before feeling adrenaline. Adrenaline needs to be pumped around the body at the normal speed of blood flow.
corrections: Blood actually pumps quite fast.  Adrenaline is pumped around the body at double the speed of normal blood flow.
raw_presuppositions: Blood pump slowly enough that there should be a delay before feeling adrenaline. Adrenaline needs to be pumped around the body at the normal speed of blood flow.
raw_corrections: Blood actually pumps quite fast.  Adrenaline is pumped around the body at double the speed of normal blood flow.