Anterior Pituitary (pathophys) Flashcards
what’s the anterior pituitary made of?
red vascular glandular tissue
Hormones inhibited by somatostatin (17)
Acetylcholine Arginine vasopressin Cholecystokinin Epidermal growth hormone Glucagon Gastrin Gastric inhibitory polypeptide Growth hormone Insulin Motilin Neurotensin Pancreatic polypeptide Secretin Serotonin Substance P Thyrotropin Vasoactive intestinal polypeptide
Results of pitutitary hormone deficiency of GH
short stature
Results of pitutitary hormone deficiency of FSH
infertility
Results of pitutitary hormone deficiency of LH
men: hypogonadism, reduced sperm count
women: hypogonadism, amenorrhea, oligomenorrhea
Results of pitutitary hormone deficiency of TSH
hypothyroidism
Results of pitutitary hormone deficiency of ACTH
hypoadrenalism, loss of pigmentation
Results of pitutitary hormone deficiency of prolactin
sheehan’s syndrome
Results of pitutitary hormone deficiency of ADH
diabetes insipidus
other name for ADH
vasopressin
Results of pitutitary hormone deficiency of oxytocin
failure of milk letdown, post-partum uterine bleeding?
secretary pituitary tumors can release which hormones? (5)
prolacting ACTH GH gonadotropins (rare) TSH (rare)
effect of prolactin excess (females, 5 items)
AMENORRHEA OLIGOMENORRHEA GALACTORRHEA (30-80%) INFERTILITY OSTEOPENIA
effect of prolactin excess (males, 4 items)
HYPOGONADISM
DECREASED LIBIDO
GALACTORRHEA (RARE <30%)
PITUITARY DEFICIENCIES
effect of ACTH excess
cushing’s disease
effect of GH excess (2)
acromegaly
gigantism
effect of gonadotropins (3 + frequency)
visual disturbances
headaches
hypogonadism
rare
effect of TSH excess (+frequency)
hyperthyroidism
rare
feedback system of GH
hypothalamus releases GHRH (+GH) and somostatin (-GH) which regulate GH output.
GH (+somotostatin?) –> liver
–> IGF-1 (feeds back to pituitary & hypothalamus)
98% of acromegaly due to
pituitary disorders releasing GH
60% of pituitary acromegaly due to
GH - cell adenoma releasing GH
25% of pituitary acromegaly due to
mixed GH-cell and prolactin-cell adenoma releasing GH
extripituitary cause of acromegaly
pancreatic islet-cell tumor (very rare) releasing GH
excess GHRH secreting types of acromegaly (2)
central ectopic (<1%) peripheral ectopic (1%)
risks of long-term GH conc elevation
malignancy:colon, esophagus, melanoma, stomach ~3x risk
arthropathy hypertension neuropathy respiratory disease CV disease carbohydrate intolerence (DM)
From where could GHRH come from that would cause gigantism? (2)
lung carcinoid tumors
islet cell tumors
From where could GHRH come from that would cause gigantism? (2)
lung carcinoid tumors
islet cell tumors
Manifestations of GH excess see in >40% of patients
Acral enlargement 100% Soft Tissue overgrowth 88% Hyperhidrosis 87% Lethargy of fatigue 73% Paresthesias 70% Joint Pain 69% Photophobia 46% Papillomas 45%
Manifestations of GH excess see in >40% of patients
Acral enlargement 100% Soft Tissue overgrowth 88% Hyperhidrosis 87% Lethargy of fatigue 73% Paresthesias 70% Joint Pain 69% Photophobia 46% Papillomas 45%
