Physio2 final pt 2

nibbs06's version from 2015-12-12 04:40


Question Answer
To measure a Dose-Response, we would use (Assay-type) Bio-Assay (when dose increases, the effect increases)
What assay is used to measure steroids? RIA & EIA (previously it was chemical assay but [steroid] is too low
For RIA & EIA, you need (2 things) Radiolabeled Ligand & a Dissociable Binder(antibodies, receptors, etc.)
What is an RIA used for? RIA uses anti-bodies to measures the [hormone] (the antigen) against labled hormone
Hormone resonse depends on (3 things) Number of receptors + hormone molecules & its affinity for the receptor
Spare Receptors are the receptors that remain at the maximum biological response
What are the 4 characteristics of a receptor? It's saturable, has strict specificity, high affinity & reversibility
What are the axis' labled as, in a Scatchard Plot? y-axis is the [R-H]/[H] (or the receptors occupied, divided by the free-hormone) and x-axis is just the [R-H]
If you have two lines in a Scatchard Plot, this means that there are TWO binding sites



Question Answer
The pituitary is encased within the ___ (tissue) & the stalk is surrounded by the ___ Sella Turcica & Pars Tuberalis
How do the anterior and posterior pituitary glands form during the embryonic period? Only neural tissue & mouth exist at first, the AP forms via Rathke's Pouch, which is formed by the upward growth from the roof of the mouth. PP is formed by the downward growth from the neural tissue/hypothalamus
The adenohypophysis is made up of (3) Pars Distalis (Anterior Pituitary), Pars Tuberalis & Pars Intermedia (@ the border between Pars Distalis & Pars Nervosa) ["D.I.T"]
The Neurohypophysis is made up of (3) Pars Nervosa (Posterior Pituitary), Infundibular Stalk & Median Eminence ["M.I.N.E"]
What's the name of the joint that's between the hypothalamus & pituitary? Median Eminence (ME)
Explain the blood supply from hypothalmaus(HP) to the pituitary lobes(AP & PP) Artery from HP goes to ME & breaks up into capillaries that pick up the RH's and then they move down the Long Portal Vessel to the AP where it turns into capillaires again that release the hormones; The AP is connected to the PP via the Short Portal Vessels that turns into capillaries at the PP to release hormones also
The blood that moves through the HP & Pituitary comes from the heart, via the (artery) Carotid Artery
Name the main blood supply to the AP, PP & the vessel that connects them together. AP has Long Portal Vessel from ME. PP has an arterial supply. & both are connected via the Short Portal Vessels
H & E stain shows that, besides the chromophobes, the most abundant cells in the AP are Acidophils (35% & RED)
An H & E Stain would classify Lactotrophs & Somatotrophs as Acidophils (RED)
An H & E Stain would classify Thyrotrophs & Gonadotrophs as Basophils (15% & BLUE)
An H & E Stain would classify Corticotrophs as Basophils(BLUE) or Chromophobes(NO COLOR) supply
The gene that transcribes ADH is found In the nuclei of the cell body that is found in the SupraOptic Nuclei
The gene that transcribes Oxytocin is found In the nuclei of the cell body that is found in the ParaVentricular Nuclei
What are Herring Bodies? They're vesicles, holding Oxytocin/ADH + Proteases, that move through the hypothalamo-hypophyseal tract to go to the terminal axon in the PP
Once ADH or Oxytocin vesicles reach the PP, what happens?(enzymatically) The protease that was transported with it, will cleave the pro-hormone to release ADH/Oxytocin and the remaining peptide is the Neurophysin
ADH's physiological effect is that it Increases BP by constricting vessels & reabsorbing water via aquaporins
What are Pituicytes? They are the support cells of the pituitary
Which "releasing hormones" are secreted from the Paraventricular Nucleus?(2) Thyroid Releasing Hormone & Corticotrophic Releasing Hormone
Which "releasing hormones" are secreted from the Arcuate Nucleus?(3) Gonadotrophic Releasing Hormone, Prolactin Inhibiting Hormone(dopamine) & Growth Hormone Releasing Hormone
Which only "releasing hormone" secreted directly from the anterior hypothalmaus? Growth Hormone Inhibiting Hormone
A Long-Feedback Loop is When the target gland feedsback to the hypothalamus
A Short-Feedback Loop is When the pituitary gland feeds back to the hypothalamus
The release of Thyroid Stimulating Hormone is based on (2 hormones) Thyroid Releasing Hormone & Somatostatin(inhibits TSH release)
In males, GnRH & FSH is inhibited by (3) Testosterone, Inhibin & Spermatogenesis
In females, GnRH & LH is inhibited by (3) Estradiol, Progesterone & Ovulation
GH release is stopped via IGF-1 stimulating GHIH in the hypothalamus or inhibiting GH release @ the AP, and GH release inhibiting the GHRH in the hypothalmamus and inhbiting its own release in the AP.
Prolactin is released from the pituitary due to The absence of dopamine; if dopamine is released, prolactin release is inhibited
The function of oxytocin is that it contracts myoepithelial cells of the mammory gland ("milk letdown") & it contracts the myometrium of uterus-parturition
ADH & Oxytocin get released at the terminus axon due to depolarization of the terminal axons
Which osmoreceptor is responsible for ADH regulation? Organum Vasculosum in the 3rd-Ventricle; they sense an increase in plasma osmolality and their neurons depolarize the dendrites that contain ADH causing calcium influx into the ADH containing neurons, causing them to be exocytosed & travel to the kidney to DILUTE the the blood osmolality by increase water reabsorbtion.
What 2 factors cause ADH release & which one has a more narrow range of change? Decreased Plasma Volume (responds to a 10-15% change in Blood Volume) & Increased Plasma Osmolality above 280mOsM/L (responds to ONLY a 1-2% change!)
What receptors inhibit the release of ADH when BP/BV is high? Baroreceptors in the Carotid Sinus & Aortic Arch, inhibit ADH release if BP/BV is high
What's the mechanism of Renin Angiotensin Aldosterone System (RAAS)? Angiogensinogen gets catalyzed by Renin(of the kidney) to become Ang-1 & Ang-1 meets ACE(of the lung) and is enzymatically converted into Ang-2, which will stimulate the release of Aldosterone(works as a vasopressin) to increase Na reabsorption(& K secretion) to increase BP
Renin is released when The blood has low osmotic concentration or when there's low blood volume
If you drink 1qt of water, what happens? blood conc. is diluted, so ADH will decrease, causing more water secretion in the urine, but also causing a decrease in [solute], thus causing an increase in aldosterone!
If you drink an isotonic solution of Gatorade, what happens? There's no initial change but eventually your BV increases so ADH decreases, which causes more water secretion but lowers [solute], so aldosterone increases
If you eat a potassium-rich meal, what occurs? K stimualtes ADH secretion; to get rid of K, aldosterone secretion is required, however, this will then cause elevated Na! Thus we need ADH to be secreted to normalize the increase in Na influx.
Which hormone inhibits ADH? Atrial Naturetic Hormone
What's the effects of Angiotensin-2 on ADH? It will increase ADH release



Question Answer
What do Syncytiotrophoblast cells create & what's the function of that active principal? Placental Lactogen(HPL); HPL doesn't have its own receptor. HPL has 10% GH potency & it has 100% prolactin potency
GH is secreted when (concentration of Glucose/FFA/AA; high or low) Low Glucose & FFA, and High Amino Acid
During a normal day, GH is eleveated During "stress"/exercise, 2 hrs after each meal & in the first 2 hours of slow-wave sleep
The biological functions of GH is (4) Increase Long-Bone Growth(stimulates IGF1), Decreases [AA] (due to increased protein synthesis); Increase [FFA](stimulates Lipolysis) & [Glucose]
A child with GH deficientcy should be given GH at which time of the day? When going to sleep since that's the time the body is building
What's the difference b/ween Gigantism & Acromegaly? Gigantism is Endochondral Growth in kids, due to xs-GH, while still having high [IGF1]; Acromegaly is Intramembranous Growth in adults due to xs-GH.
Why does a GH producing tumor have lactogenic effects? Only in pathological situations (tumor), GH will have a 10% affinity to the Prolactin(PRL) receptor, meaning it has a 10% PRL potency.
PRL is secreted from the _________ cells (___ophile cell) of the anterior pituitary PRL is secreted from the Mammotroph Cells (Acidophile Cell) of the AP
PRL secretion is stimulated by (2) TRH & VIP
Why do females have slightly larger pituitary glands? They have more lactotroph cells than males
Which hormone is unique in increasing prolactin? & How(2)? Estrogen; it increases the number of lactotroph cells & it decreases the cells receptor-sensitivity to dopamine
PRL increases at which point of the day/night?During REM sleep(2 hours after you go to sleep)
What causes PRL to increase? & How?(4) Decreased Dopamine causes increase PRL due to Stress & "Suckling", during orgasams & during periods of eating.
HPL increases during which trimester of pregnancy? Third Trimester
In males, PRL isn't necessary, but what effects does it have in their bodies? PRL stimulates prostate growth & PRL work synergestically w/ LH in the Leydig Cells to stimulate Testosterone Production.
What does PRL do in women & what are the side-effects? Regulates Lactational Process; Chronically Elevated PRL can cause infertility & cessation of their menstrual cycle (may function as a birth-control)
What's the functional structure of the mammary gland? The Alveolus
The alveolus is made up of (2) The Myoepithelial Cells & the Alveolar/Lactating Cells
Oxytocin causes "milk letdown" by binding to its receptor on the smooth muscle of myoepithelial cells and expelling the milk into the ductal system.
What is the function of the Alveolar Cells (or Lactating Cells)? They produce & move the milk into the lumen of the alveolus & when the myoepthelial cells contracts, it moves that milk into the ductal system.
Which hormones are requried to regulate milk-production? Prolactin(the regulatory hormone), Cortisol, Insulin & T3.
Which cell-mutations are the cause of most breast cancers? Ductal Cell mutations will cause normal cells to become neoplastic cells.
What is a lobule? 200 alveloi cells that each have a duct connecting to it & all of those ducts come together to make a larger duct(interlobular duct); all of this is wrapped in tissue, forming a lobule.
What does the lobe of a mammary gland consist of (name structures that lead up to the nipple)? 26 lobule's are wrapped together in a tissue & their interlobular ducts converge to form the interlobar duct & all of the interlobar ducts come together to form the Lactiferous Duct that is connected to the nipple.
What is witches milk and how does it come about? It's a watery fluid(not milk) secreted by the nipple of neonate's/newborn's due to the high estrogen & progesterone exposure, which stimulate the production of the ducts.
From birth to puberty, what happens with the development of the female mammary gland ? There's growth of their Ductal Tree, from Atrophic Ducts, due to their exposure to the surging levels of estrogen and a small amount of progesterone. The ductal system partially develops, & the gland becomes engorged with fat!
At pregnancy, what happens with the development of the female mammary gland? Estrogen will stimulate Ductal-Development & Progesterone will stimulate Lobulo-Alveolar Development.
If we removed the pituitary, the adrenals & ovaries, & injected estrogen + progesterone, what would happen? NOTHING!
If we removed the pituitary, the adrenals & ovaries, & we injected Estrogen + Glucocorticoids + GH, what would happen? Ductal Development
If we removed the pituitary, the adrenals & ovaries, & we injected Estrogen + Progesterone + Glucocorticoids + GH + PRL , what would happen? Lobulo-Alveolar Growth
GH is known to help with Mammary Gland development, however, GH doesn't increase during preganancy, so how is it stimulated during preganancy? HPL
During pregnancy, a female cannot lactate, why? Estrogen & Progesterone INHIBIT milk product-formation, they block the "read-off" of the genes necessary to produce milk. Post-pregnancy, you sloth off the placenta & that lowers the supply of these hormones.
What hormonal changes initiate lactation? Decreased Estrogen & Progesterone(loss of placenta), Increased PRL & ACTH(due to suckling) and an Increase in Cortisol
How does "suckling" cause milk ejection? Mechanoreceptors on the nipple are stimulated and they stimulate the oxytocin secreting nuclei via depolarization; the Paraventricular Nuclei causes oxytocin to get released from the PP and into the blood, to bind to its receptor on the myoepithelial cells
What's the effect on PRL during suckling? The mechanoreceptors of the nipple will inhibit the release of dopamine from the Median Eminence, thus causing an increase in PRL that will go to the alveolus to produce milk for the next feeding cycle.
Infertility is commonly caused by Increased PRL