So I'm skipping a large part of the study guide, going straight to the part that has to do with this week's test. Call it egotistical but I want a good grade. Later I'll go back at least to section III before the final (since apparently III and IV make up roughly 70% of the test).
Name factors that determine strength of physiological response caused by
hormone.
Strength of hormonal a response is dependent on how receptive the target cell is, and how concentrated the dosed hormone is released in the blood (the more the greater the response).
List the three ways the body regulates hormonal production. Explain humoral,
neural and hormonal regulations of hormone production. Compare negative and
positive feedback mechanisms. Give examples of hormones in each category.
The body regulates hormones in these three ways:
1. Humoral stimulation, or in other words, the body constantly "tasting" the blood to make sure it has the right composition.
2. Neural stimulation- this system generally just tends to do it's thing automatically. By sending out it's own transmitters it can manipulate the endocrine system.
3. Endocrine stimulation- One endocrine gland affects another endocrine gland, which affects another endocrine gland. In a snowball sort of way, every endocrine gland can influence another.
Fortunately there are blocks in place to prevent it from getting too unruly. Positive Feedback simply means that the endocrine glands feed off another in a self perpetuating cycle. Negative Feedback conversely means that one endocrine gland in the perpetuating loop has had enough and tells the others to close shop.
Explain the types of hormone interaction at the target cells.
Easy! McVay loves to cover this one as it's the basis for hormone-cell interaction. Simply put, amino acid-based hormones (amino acids, peptides, poly-peptides, and proteins) are all dissolved in the plasma of the blood and attach to the surface of the target cell when passing by. On the other hand, the more complex molecules like steroids and other fatty molecules (anyone know any others?) require special protein transports to get to their destinations. Upon arrival steroids will pass through the membrane (because like dissolves/passes through like) and begin transcription.
Name an endocrine gland responsible for neural regulation of endocrine system.
Explain how releasing and inhibiting factors regulate hypophyseal activity
(hypothalamo-pituitary axis). List hormones of hypothalamus* and their effects
on pituitary gland.
Hypothalamus regulates both neural and endocrine systems. Apparently the pituitary gland is the puppet of the hypothalamus, doing its bidding like the mind controlled servant that it is. The two function together quite well- the hypothalamus releases hormones that switches both anterior and posterior pituitarys on, the anterior pituitary releases its hormones into the body, the hypothalamus is satisfied with the reaction and produces inhibiting "factors" (hormones).
Listing the hormones and their effects is well above my pay-grade. (will probably come back to this)
Listing the hormones and their effects is well above my pay-grade. (will probably come back to this)
Recall anatomy of pituitary gland and hypophyseal portal system. Explore the
differences between neurohypophysis and adenohypophysis.
Not only does the hypothalamus reign supreme over the pituitary gland but it does it in two separate ways: through hormonal regulation (on the anterior pituitary) and neural stimulation (on the posterior pituitary, which I believe does have a small hormone gap the jump as part of the process, which then starts off the neural response).
Adenohypophysis= anterior pituitary
Neurohypophysis= posterior and is considered part of the hypothalamus because of its neuronal connection.
Adenohypophysis= anterior pituitary
Neurohypophysis= posterior and is considered part of the hypothalamus because of its neuronal connection.
List hormones of anterior pituitary* and explain their role in regulation of
endocrine system. What abnormalities result from inadequate production of these
hormones? Based on the function of these hormones, predict the symptoms in
patients with these abnormalities.
All hormones of the anterior pituitary (AP) are called Adenohypophysis. They are also more commonly referred to as trophic hormones, and are listed next:
Growth hormone (GH)- not only affects epiphyseal plates but every cell in the body. Causes production of somatomedins by muscle, liver, and bone (also promotes growth and mediates GH). Too little can lead to pituitary dwarfism. Too much causes gigantism (children) and acromegaly (adults).
Prolactin- stimulates milk production and parental behavior (aka child attachment). Hypothalamus sends Prolactin-releasing hormone (PRH, a seratonin) or Prolactin-inhibiting hormone (PIH, a dopamine) to anterior pituitary (AP) as part of regulation. Prolactin is known to cause tumors in the AP, which can cause headaches, inappropriate lactation, off-beat menstrual cycles, and male impotence.Adrenocorticotropic hormone (ACTH)- stimpulates production of glucocorticoids (cortisol, corticosteron) by the adrenal cortex (which is also partly covered later!). Hypothalamus releases corticotropin releasing hormone (CRH) to increase ACTH production, which follows the circadian rhythm. In other words, ACTH helps as wake up in the morning and taper off at night by flowing or limiting the amount of energy to us, and it is all controlled by CRH from the hypothalamus.
Thyroid stimulating hormone (TSH)- released by AP. As usual it starts with hypothalamus that releases thyrotropin-releasing hormone, which in turn causes AP to release TSH, which activates thyroid, which makes thyroxin that affects target cell and turns off (negative response) AP and hypothalamus.
Gonadotropins- includes Luteinizing Hormone (LH, promotes synthesis of gonadal hormones in ovaries and testes) and Follicle-Stimulating Hormone (FSH, promotes development of egg and sperm). Both are only used after puberty starts, and are activated by Gonadotropin-Releasing Hormone (GnRH).
Something that I've noticed is that everything that comes from the hypothalamus has "Releasing Hormone" as part of the name. This makes it easy to identify whether it is coming from the hypothalamus or the AP.
List hormones of posterior pituitary*. Describe the role of oxytocin during labor
and milk ejection. Explain why the production of oxytocin* increases during/
after labor. Explain the role of ADH in fluid/electrolyte balance. What
abnormalities result from inadequate production of this hormone? Apply your
knowledge of effects of ADH on target cells to predict symptoms in patients with
inadequate production of this hormone.
The two major hormones of the posterior pituitary are Oxytocin and Antidiuretic hormone (ADH).
Oxytocin is important during birth because it increases uterine contractions via a positive feedback cycle that begins with dilation of the cervix. It is important during breast feeding because it causes the smooth muscle to push the milk out. Lastly, it is the bonding hormone for moms, causing them to become more effectionate with the newborn. This can be helpful when the mother experiences post-partum depression, getting a distant mom to start feeling close with the newborn.
In males it causes ejaculation lol.
Antidiuretic means "retain water" ("against peeing"). When osmorecepters taste too many electrolytes in the blood (humoral regulation) then ADH is sent to the kidneys to retain water. More water is absorbed back into the body and extra concentrated pee is produced. ADH also causes vasoconstriction, raising blood pressure.
If a person cannot produce enough ADH then there is a good chance they will develop diabetes insipidus, where the body can't produce concentrated urine and constantly suffers from an electrolyte balance.
Too much ADH leads to sodium/electrolyte deficiencies, water retention, and other problems having to deal with holding onto too much water and not enough other stuff.
Both posterior pituitary gland hormones are produced in the hypothalamus (paraventricular nucleus and supraoptic nucleus, which are names of different types of nuclei that are both found in the hypothalamus). Both also use the PIP2 mechanism to affect the target cells.
Oxytocin is important during birth because it increases uterine contractions via a positive feedback cycle that begins with dilation of the cervix. It is important during breast feeding because it causes the smooth muscle to push the milk out. Lastly, it is the bonding hormone for moms, causing them to become more effectionate with the newborn. This can be helpful when the mother experiences post-partum depression, getting a distant mom to start feeling close with the newborn.
In males it causes ejaculation lol.
Antidiuretic means "retain water" ("against peeing"). When osmorecepters taste too many electrolytes in the blood (humoral regulation) then ADH is sent to the kidneys to retain water. More water is absorbed back into the body and extra concentrated pee is produced. ADH also causes vasoconstriction, raising blood pressure.
If a person cannot produce enough ADH then there is a good chance they will develop diabetes insipidus, where the body can't produce concentrated urine and constantly suffers from an electrolyte balance.
Too much ADH leads to sodium/electrolyte deficiencies, water retention, and other problems having to deal with holding onto too much water and not enough other stuff.
Both posterior pituitary gland hormones are produced in the hypothalamus (paraventricular nucleus and supraoptic nucleus, which are names of different types of nuclei that are both found in the hypothalamus). Both also use the PIP2 mechanism to affect the target cells.
Explore anatomy of thyroid gland. List three hormones* produced there. Explain
how thyroid hormones (T3, T4) are produced and regulate metabolic rates in the
body. Apply your knowledge of effects of thyroid hormones on target cells to
predict symptoms in patients with inadequate production of these hormones.
What are these abnormalities?
It's below the Adams apple on both sides with a small connection between both sides. Study the images to get the microscopic structure.
It produces triiodothyronine (T3) (10%), thyroxine (T4) (90%) and calcitonin. Iodine is mixed with the colloid inside of the thyroid gland to produce T4. T3 is much more powerful than T4 although it is produced much less frequently, but is converted frequently to T3, especially in the kidneys and liver. Although it is an amino-based hormone it is one of the few that cannot travel alone in the bloodstream and must attach to other proteins (usually liver proteins like albumin and thyroxin) to reach target cells (and affects the nucleus of the celll). It is required by all cells, and is used to increase metabolic activity. This means it throws the cell into gear, consuming oxygen, sugars, ATP, fat, and producing more heat.
It also regulates growth and development, which is important the fetus and infants (lack= cerebral damage).
Deficiencies manifest in Simple Goiter, dwarfism, and retardation.
It's below the Adams apple on both sides with a small connection between both sides. Study the images to get the microscopic structure.
It produces triiodothyronine (T3) (10%), thyroxine (T4) (90%) and calcitonin. Iodine is mixed with the colloid inside of the thyroid gland to produce T4. T3 is much more powerful than T4 although it is produced much less frequently, but is converted frequently to T3, especially in the kidneys and liver. Although it is an amino-based hormone it is one of the few that cannot travel alone in the bloodstream and must attach to other proteins (usually liver proteins like albumin and thyroxin) to reach target cells (and affects the nucleus of the celll). It is required by all cells, and is used to increase metabolic activity. This means it throws the cell into gear, consuming oxygen, sugars, ATP, fat, and producing more heat.
It also regulates growth and development, which is important the fetus and infants (lack= cerebral damage).
Deficiencies manifest in Simple Goiter, dwarfism, and retardation.
Explain the role of calcitonin* and parathyroid* hormone in regulation of calcium
blood concentration. Predict the outcomes for the patient with hypoparathyroidism.
Calcitonin and parathyroid work constantly to keep the blood concentrations of calcium in check. Calcitonin targets osteoblasts, telling them to take calcium out of the blood to store in bone. Conversely, parathyroid hormone targets the osteoclasts, making them dissolve bone for use in the blood. It also tells the kidneys to hold onto calcium during filtration.
Hypothyroidism is a deficiency of calcium in the blood. This affects everything that uses calcium, including muscles, brain, and nervous system. It's used a lot!
Calcitonin and parathyroid work constantly to keep the blood concentrations of calcium in check. Calcitonin targets osteoblasts, telling them to take calcium out of the blood to store in bone. Conversely, parathyroid hormone targets the osteoclasts, making them dissolve bone for use in the blood. It also tells the kidneys to hold onto calcium during filtration.
Hypothyroidism is a deficiency of calcium in the blood. This affects everything that uses calcium, including muscles, brain, and nervous system. It's used a lot!
Explore gross and microscopic anatomy of adrenal gland. List three zones of
adrenal cortex and give examples of hormones* produced there. What is the role
of aldosterone* in regulating blood pressure and electrolyte balance? Apply you
knowledge of aldosterone’s function to explain symptoms of Conn’s syndrome.
The outer section is called the cortex, the inner the medulla. Each part produces very different hormones.
Three zones of cortex:
1. Zona glomerulosa- mineralcorticoids
2. Zona fasciculata- glucocorticoids
3. Zona reticularis- gonadocorticoids
All are considered "corticosteroids"
Aldosterone causes water retention (same effect as ADH) by telling the kidneys to retain sodium- water follows the sodium (Na+) along the concentration gradient. It also tells the kidneys to get rid of potassium (K+). Consequently the extra fluid in the system raises blood pressure.
Conn's syndrome is overproduction of Aldosterone, which leads to too much water and Na+ in the body and a lack of K+. This causes hypertension, edema, and muscle weakness (action potential can't be generated).
The outer section is called the cortex, the inner the medulla. Each part produces very different hormones.
Three zones of cortex:
1. Zona glomerulosa- mineralcorticoids
2. Zona fasciculata- glucocorticoids
3. Zona reticularis- gonadocorticoids
All are considered "corticosteroids"
Aldosterone causes water retention (same effect as ADH) by telling the kidneys to retain sodium- water follows the sodium (Na+) along the concentration gradient. It also tells the kidneys to get rid of potassium (K+). Consequently the extra fluid in the system raises blood pressure.
Conn's syndrome is overproduction of Aldosterone, which leads to too much water and Na+ in the body and a lack of K+. This causes hypertension, edema, and muscle weakness (action potential can't be generated).
Explain the circadian rhythms in production of cortisol*. Apply you knowledge of
hormone’s effects to explain symptoms of Addison’s and Cushing’s syndrome.
Cortisol is released in accordance with our circadian rhythm, putting out more while we're awake and turning off at night (or whenever we sleep...). It gets the body to take energy from all the sources, sugar, fat, and proteins, and use it for activity. Production is regulated by ACTH (found in the anterior pituitary section), and returns a negative feedback to ACTH. Oddly enough cortisol also suppresses our immune response.Addison's syndrome (lack of adrenal gland hormones)- hypoglycemia, hyperpigmentation (don't know why...), dehydration, and excessive acid and K+ in blood.
Cushing's syndrome (excessive corticosteroids)- excessive sugar in blood, obesity, poor wound healing, hypertension, stretch marks, and masculine hair growth.
Explain how hormones of adrenal medulla* help body to cope with stress. What
abnormality results from overproduction of these hormones?
Epinephrine (80%) and norepinephrine (20%) cause an increase in heart rate and contractibility, increased blood pressure, peripheral vasoconstriction (which is just another way of increasing blood pressure...), and hyperglycemia. Glucocoricoids are much more effective but these are good for quick situations.
Overproduction can be cause by tumors on adrenal medulla, leading to hyperglycemia, tachycardia (fast heart rate), and hypertension.
All hormones of adrenal gland prepare for stress!
Readers, sorry if this was a long dry read! It was definitely a long, dry write. There are a lot of hormones to be known for this quiz. It's crazy how much material can pile up from not having a quiz for two weeks.
Hang in there though! Term is almost over :)
