Something is wrong with the gland (target organ)
primary pituitary disease
something wrong with hypothalamus (Rare)
tertiary pituitary disease
Something wrong in pituitary gland
secondary pituitary disease
CRF→ corticotrophs release
ACTH
TRF→ thyrotrophs release
TSH
FSH/LH-RF→ gonadrotrophs release
FSH/LH
GHRF→ somatotrophs release
GH
PIF (dopamine)→ lactotrophs inhibited from releasing
PL
______ is the most common anterior pituitary tumor
Adenoma
*prevalence of 16%
histology:
overgrowth of 1 cell type
adenoma
*normal has a mixture of cell types
Most common (30%) Produces galactorrhoea and menstrual disturbances
Prolactinoma (chromophobe)
produces gigantism in children and acromegaly in adults (15%)
GH-secreting (esinophil)
Producings Cushings disease
ACTH-secreting (basophil)
No hormone production (27%)
null cell
how does pituitary adenomas produce clincal disease
- excess hormone production
2. pressure/mass effect
sx of elevated intracranial pressure due to adenomas
Headache
nausea/vomitting
vision defects due to pressure/mass effect from adenomas
- can result in bitemporal hemianopsia
* pituitary is close to the optic chiasm
anterior pituitary release what hormones
ACTH GH TSH FSH, LH Prolactin MSH
posterior pituitary release what hormones
ADH aka vasopressin
Oxytocin
when does GH spike or get released
from deep sleep
*typically undetectable most of the day
GH raises ___
blood glucose levels
- Binds surface receptors on bone and fat
- Indirect action through IGF-I (somatomedin C)
- Leads to increased protein synthesis
- Accelerates breakdown of fat
GH
inhibited by undernutrition and hyperglycemia
GH