Lecture 3 1/30/14 Flashcards
G-Protein is a Perfect Example of What?
Activating intra cellular pathway, it dissociates the first alpha subunit and it goes down and could do a lot of things inside the cell
Glands of the Endocrine System
Pituitary Gland - Master gland. Produces about 7 hormones. Also known collectively as the hypophysis.
Location is: Resides within the Sella Turcica, turkish saddle. Connected to the Hypothalamus via through the infundibulum. Divot in the center of the sella turcica is Hypophyseal Fossa because it resides within that structure.
Pituitary Gland Divides into what?
Anterior and Posterior Pituitary Glands
Anterior Pituitary Gland
known as the Adenal Hypophysis - Adenal means “Glands” or “Glandular”. Adenal Carcoma - Glandular tumor or Adenoma is a glandular tumor. Adenal Carconoma is a pancreatic cancers.
Anterior Pituitary Gland is Derived from?
Structure known as the Rathke’s Pouch
Rathke’s Pouch
is the portion of the pharynx that invaginates and moves posteriorly that becomes the anterior pituitary gland.
the pharyngeal tissue that pulls backwards and separates from the pharynx that becomes a separate structure: The Anterior Pituitary Gland
Phosphodiasterase (PDE)
breaks down cAMP after its been formed. We don’t want cAMP turned on all the time. So we activate it, we make cyclic amp which it is the secondary messenger and after we do that we want to break it down immediately to AMP (Adenosine Monophosphate)
Mammillary Body
Coordinates chewing motion or chewing with the sensation of smell.
Blood Flow for the Anterior Pituitary Gland
There’s a vessel that comes in through the top and the bottom. The entire pathway or blood supply is known as the Hypothalamic Hypophyseal Portal System. A vessel comes into the capillary bed and down below there is another capillary bed. Because we start up in the hypothalamus, and then we end up down in the hypophysis in the anterior pituitary gland. The hypothalamus is the master gland of the master gland.
Hypothalamic Hypophyseal Portal System
is a connected blood supply between those two structures that allows the releasing hormones, coming from the hypothalamus, to have an effect on the anterior pituitary gland. These hormones can be produced in very small amounts.
Hypothalamus produces releasing hormones that will affect what?
The Anterior Pituitary Gland
Blood Goes through what?
Goes through the hypothalamus and comes down and out through the anterior pituitary gland
What happens in the Arterials and Arteries?
No Gas exchange and no nutrients exchange
What happens in the Capillary Beds?
Gas, waste, nutrients get exchanged
Process of the Releasing Hormones
Releasing hormones go down and end up in the blood supply to go to the Anterior Pituitary Gland where they are simply diffused and end up by telling the Pituitary Gland to do what it’s suppose to do, release this hormone and that hormone.
Why do we call it a Portal System or Portal Vessel?
Because it is a vessel located between two capillary beds.
3 Different Cell Types
Acidophiles
Basophils
Chromophobes
Acidophiles
stain pink
Secrete : HGH produces cells and the prolactin producing cells.
Acid Stains - more of a pink color stain; Some cells will pick it up, some won’t pick it up.
Basophils
Have a more dark purple blue stains
Secrete: Thyroid Stimulating Hormone, Adrenocorticotropic Hormone, Follicle Stimulating Hormone, Lutenizing Hormone, Melanocyte Stimulating Hormone
Chromophobes
Don’t pick up color. They are clear stained
Hormones of the Anterior Pituitary Gland
hGH - Human Growth Hormone
hGH
Human Growth Hormone also known as Somatotropin, soma means body, tropin means growth effect. It causes body growth.
3 Functions of hGH
- Responsible for cell growth and multiplication.
- Allows protein to be shuttled into the cell via the cAMP pathway. Tissue re-generation. Google: Jeffrey Life.
- hGH will increase mitotic activity meaning potential for tumor growth and hGH will increase lipid and glucose metabolism.
Negative Feedback Loop
Decrease in blood sugar that’s gonna go to the hypothalamus. HGH is involved in sugar metabolism
HGH goes into the Anterior Pituitary Gland, which releases hGH. hGH has a large effect on the liver. And the liver will then release IGF’s, also known as Somatomedians. Also it will release sugar.
