The most common cause of hyperpituitarism is an
adenoma arising in the anterior lobe. Other, less
common causes include hyperplasia and carcinomas
of the anterior pituitary
pharmacological treatment : 1. somatostatin receptor
agonists (also known as somatostatin receptor ligands
[SRLs] or somatostatin analogues), 2. dopamine
analogues 3. GH receptor antagonists
Pituitary Adenomas
Pituitary adenomas are benign neoplasms of the
anterior lobe of the pituitary and are often associated
with excess secretion of pituitary hormones treated
by surgical resection, medical therapy, and radiation
therapy.
1-The most dramatic effect of GH is stimulation of
postnatal linear growth.2- Local production of IGF-1
3-GH stimulates lipolysis ,GH increases
gluconeogenesis ,GH increases protein synthesis in
muscle.etc.
Control of GH Secretion
Hypoglycemia ,Hyperglycemia
,exercise,Somatostatin Sex
steroids ,sleep
Assessment of GH
1-Insulin Stress Test. 2-Glucose
Tolerance Test. 3-Measurement
of IGF-1 to assess GH excess (not
confirmative).
Water-soluble ,Short half-life (minutes), Pulsatile
secretion,Act on cell surface receptors Act via
second messenger (cAMP, a rise in intracellular
Calcium, or a receptor tyrosine kinase).
3-Steroids: cortisol, etc
Longer half-life (hours) Act on
intracellular receptors Act on
DNA to alter gene transcription