Path 5 Endocrine Intro, Pituitary Flashcards
Anterior lobe & posterior lobe of pituitary names
Adenohypophysis
Neurohypophysis
Anterior v Posterior function
Anterior produces via hypothalamus, Posterior secretes via neurons
Larger lobe of the pituitary
Anterior
5 anterior cells & hormones
- Somatotrophs - Growth Hormone
- Corticotrophs - POMC (ACTH, B-MSH)
- Thyrotrophs -TSH
- Gonadotrophs - FSH, LH
- Lactotrophs - Prolactin
Somatotroph
GH -> Somatomedins (liver) ->
Somatotroph regulation
Hypothalamus:
- ++ GHRH
- – Somatostatin (GIH)
Corticotroph
POMC (pro-opiomelanocortin) split into
a. ACTH -> adrenal -> cortisol and androgen
b. B-lipotropin -> B-MSH and B-endorphins
Corticotroph regulation
++ Hypothalamic CRH (corticotropin releasing hormone)
Thyrotroph
TSH (Thyroid Stimulating Hormone) -> Thyroid follicle growth
Thyrotroph regulation
++ Hypothalamic TRH (Thyrotropin releasing hormone)
Lactotroph/mammotroph
Prolactin -> lactation
Lactotroph regulation
– Prolactin inhibiting factor (Dopamine)
Gonadotroph
FSH -> follicle formation
LH -> ovulation and corpus luteum formation
Gonadotroph regulation
++ Hypothalamic GnRH
Posterior pituitary anatomy
Pituicytes (glial cells from hypothalamus) travel through stalk into neuro hypophysis
2 posterior cells & hormones
Pituicytes
- Oxytocin
- ADH (vasopressin)
Oxytocin function, regulation
Stimulates uterine contraction and milk ejection
-Regulated by cervical dilation and nipple stimulation
ADH function, regulation
Water retention in collecting ducts
-Controlled by baro and osmoreceptors
Most common cause of hyperpituitarism
Pituitary adenoma
Nonfunctioning adenoma clinical presentation
Temporal hemianopsia
Hypopituitarism
Headaches
Pituitary adenoma histo
Cellular monotony
Loss of normal reticulin network
2 Familial pituitary adenoma syndromes
- MEN1 mutation
- Carney’s complex
Carney’s complex
Endocrine adenomas, cardiac myxomas, pigmented skin lesions
MEN1 mutation
Hyperplasia of pituitary, thyroid, parathyroid, adrenal cortex, pancreas