Normal microscopic appearance of anterior lobe hormones
Describe the TSH, FSH, and LH family of anterior pituitary hormones
These are all glycoproteins consisting of identical alpha subunits and unique beta subunits (similarly, human chorionic gonadtropin of the placenta shares these features)
Describe ACTH family derivation
All derived from pro-opomelanocortin (POMC) which is then manipulated to form ACTH, y- and b-lipotropin/endorphin, or melanocyte-stimulating hormone (MSH)
What is the effect of both POMC and ACTH containing some MSH activity?
Conditions that are associated with over-expression of these products (i.e. Addison disease) can produce skin pigmentation
Generation of ACTH is inhibited by what?
Overview of GH production
Produced by somatotrophs when stimulated by GHRH and is important in body growth and metabolism. Secretion starts at childbirth and increases vastly at puberty and then gradually decreases from that point in life until death and is only secreted during Stage III/IV Sleep (much more so in younger people)
NOTE: Insulin like-growth factor I and thyroid hormones can act as inhibitors for release of GH and GHRH
Describe Prolactin regulation
Released from the anterior pituitary and is under tonic inhibition by dopamine but when a stimulus is sensed, this inhibition is released due to neural input into the hypothalamus.
The release of prolactin is augmented by what?
oxytocin, AVP, and thyroid releasing hormone
What happens when the stimulus for prolactin goes away?
prolactin itself provides a negative feedback to produce more dopamine