Download endocrine gland

 Affects
almost every cell, organ,
and function of the body
 The
endocrine system is closely
linked with the nervous system
and the immune system
 Negative
feedback mechanism
 Hormones
◦ Steroid: act inside the cell
◦ Peptide (protein): act on cell
surface
◦ Amine: mechanism of action is
same as that of peptide hormone



Hormone levels in the blood are mostly
maintained by negative feedback
A stimulus or low hormone levels in the
blood triggers the release of more
hormone
Hormone release stops once an
appropriate level in the blood is
reached
 Most
common stimuli
 Endocrine glands are
activated by other
hormones
 Example:
◦Anterior pituitary hormones
Figure 9.2a
Changing blood levels of certain ions
stimulate hormone release
 Humoral indicates various body fluids
such as blood and bile


Examples:
◦ Parathyroid hormone
◦ Calcitonin
◦ Insulin
Figure 9.2b
◦ Nerve impulses stimulate hormone
release
◦ Most are under the control of the
sympathetic nervous system
◦ Examples include the release of
norepinephrine and epinephrine by
the adrenal medulla
Figure 9.2c
Table 9.1 (1 of 4)
Table 9.1 (2 of 4)
Table 9.1 (3 of 4)
Table 9.1 (4 of 4)
 HYPOTHALAMUS
Produces
hormones
(called
factors) carried via blood in
hypothalamic hypophyseal portal
system to anterior pituitary.
 This
hormones/factors
are
involved in normal feedback
controls
 Releasing
hormones (RH)
cause increased secretion by
the anterior pituitary
 Secondary effect on glands
controlled by the pituitary
 Excess RH causes
hypersecretion of other
glands
 Inhibiting
hormones (IH)
 cause decreased secretion by
anterior pituitary
Secondary effect on glands
controlled by the pituitary
Excess IH causes
hyposecretion of other glands
PITUITARY GLAND
 Located at the base of the
brain.
 Directly affects the function of
the other endocrine glands.
 Promotes growth of body
tissues
Hormone Secreted
Growth hormone
Main Functions
growth of skeletal muscle, bone, cartilage
increase protein synthesis
stimulates lipolysis for ATP production
reduces glucose use for ATP production
increase release of stored glucose from liver
raises blood glucose level (diabetogenic effect)
triggers thyroid hormone release from thyroid
Thyroid-stimulating hormone indirectly enhances basal metabolism of cells via thyroid activation
stimulates glucocorticoid (cortisol) secretion from adrenal cortex
Adrenocorticotropin hormone indirectly enhances "stress-response" via adrenal activation
Prolactin
Follicle-stimulating hormone
Luteinizing hormone
promotes milk production by mammary glands
induces spermatogenesis in testes of males after onset of puberty
induces 2o oocyte development in ovaries of females after onset of puberty
stimulates growth of ovarian follicles (granulosa cells)
stimulates estrogen production from ovaries
enhances 2o oocyte maturation in ovaries
induces ovulation
maintains corpus luteum for first two weeks after ovulation
stimulates testosterone production from testes
Summary:
The
Hormones
of the
Pituitary
Gland
Figure 18–9
Hormone Secreted
Oxytocin
Antidiuretic hormone
Main Functions
stimulates uterine contraction (labor contractions)
stimulates milk let-down reflex
stimulates water retention by renal collecting ducts
in kidneys
inhibits sweat glands in skin
stimulates vasoconstriction in skin (hence name
"vasopressin")
ANTERIOR PITUITARY
•Hyperpituitarism
•Hypopituitarism
POSTERIOR PITUITARY
•Diabetes Insipidus
•SIADH (Syndrome of Inappropriate secretion of
Antidiuretic Hormone)

Children: GIGANTISM
 occurs in childhood before the closure
of epiphyses of the long bones
 7-8 Ft. tall, weak, lethargic
Adult: ACROMEGALY
◦ occurs after the closure of epiphyses of the long
bones
o Bone and tissue deformity, enlargement of the viscera
w/o an ↑ in height
 Excessive growth occurs in the feet, hands, nose,
chin, visceral organs
 S/sx: large hands & feet, thickening & protrusion
of jaw, arthritic changes, visual disturbances,
diaphoresis, oily & rough skin, organomegaly,
hypertension, dysphagia, deepening of voice
Treatment:
Emotional support
Frequent skin care
Pharmacologic & non-pharmacologic
interventions for joint pains
Pharmacotherapy
◦ Bromocriptine (Parlodel) to lower GH
levels and prolactin levels.
Prepare for radiation of pituitary gland or
transphenoidal hypophysectomy

It is characterized by excessive
retention of water by the renal
tubules
 Secondary to excessive secretion of
ADH (with a subnormal serum
osmolality)
 They cannot excrete a dilute urine
Retain fluid---dilutional
hyponatremia
 Often
non-endocrine origin
Bronchogenic CA  malignant lung
cells synthesize and release ADH
Can also occur in pts. With severe
pneumonia, pneumothorax and other
lung disorders
Head injury, Tumor, Infection,
Surgery  directly stimulate P.G.
◦ Some medications (e.g. vincristine,
phenothiazines, tricyclic
antidepressants, thiazide diuretics)
 Either directly stimulate the P.G. or
 Increase the sensitivity of the renal
tubules to the circulating ADH

S/Sx:
Signs of fluid overload
changes in LOC & mental status;
weight gain (edema),
HPN,
tachycardia,
hyponatremia (DILUTIONAL)
 Excessive retention of water is not
accompanied by proportionate retention of
sodium.
Management:
Eliminate the underlying
cause
Restrict Na and fluids as
prescribed
Bec. retained water is excreted
slowly by the kidneys
Monitor I & O and daily weight;
Administer diuretics & monitor IV
fluids carefully
Furosemide (Lasix)
Monitor fluid & electrolyte balance and
replace loss as prescribed
Meds:
Demeclocycline (Declomycin)
inhibits ADH-induced water reabsorption
& produces water diuresis
Monitor for possible nephrotoxicity
USUALLY BENIGN
 But because of their location and
effects on hormone production they
produce life-threatening effects


3 principal types:
◦ Eosinophilic cells
◦ Basophilic cells
◦ Chromoprobic cells
 Clinical
manifestations:
◦ EOSINOPHILIC TYPES:
 Develop early in life--GIGANTISM (7fT. TALL)
 Can bee too weak and lethargic
and can’t hardly stand
 IF IT DEVELOPS DURING ADULT
LIFE-ACROMEGALY
◦EOSINOPHILIC TYPES: (cont.)
 Severe headache
 Visual disturbances – Loss of color
discrimination, diplopia, blindness in a
portion of a field of vision.
 Decalcification of the skeleton,
 Muscular weakness,
 Endocrine disturbances (similar with
hyperthyroidism)
 Clinical
manifestations:
◦ BASOPHILIC TYPES:
 Gives rise to Cushing’s syndrome –
hyperadrenalism features
 Masculinization and amenorrhea in
females
 Truncal obesity
 HPN
 Osteoporosis
 Polycythemia
 Clinical
manifestations:
◦CHROMOPHOBIC TYPES:
 90% OF PITUITARY TUMORS
 PRODUCES NO HORMONES--destroys the rest of the
Pituitary gland ---resulting in
HYPOPITPUITARISM
◦ CHROMOPHOBIC TYPES: (cont.)
 Physical characteristics
 Obese and somnolent, Has fine, scanty
hair, Dry soft skin, Pasty complexion,
and Small bones
 HEADACHE, loss of libido and visual
defects is common
 Other signs and symptoms:
 Polyuria, polyphagia, and dec. BMR and
subnormal body temp
DIAGNOSTIC EXAMS
CT/ MRI SCAN
 Detects presence and extent of Pituitary
Tumors
Serum
levels of pituitary hormones
and hormones of target organs
MANAGEMENT:
Emotional support frequent skin care;
pharmacologic & non-pharmacologic
interventions for joint pains


Pharmacologic mgt.
BROMOCRIPTINE (PARLODEL)
 Dopamine Agonist
 lower GH levels and prolactin levels
 OCTREOTIDE (SANDOSTATIN)
 Synthetic analog of GH  inhibit production/ release of
GH
 Can be used preoperative to decrease tumor size and
improve pt’s condition

Prepare for radiation of pituitary gland or
hypophysectomy

Removal of pituitary gland

TRANSPENOIDAL Hypophysectomy
 incision is made under the upper lip.

Post-operative care:
 Monitor V/S, neurological status & LOC
 Elevate head of bed (To prevent cerebral edema)
 Monitor for increased intracranial pressure & any
postnasal drip (RHINORRHEA) which might be CSF
Post-operative care:
 Avoid sneezing, coughing & blowing nose
 Monitor for temporary diabetes insipidus (
due to removal of the pituitary gland which
secretes vasopressin)
 Monitor I & O & water intoxication
 Administer antibiotics, analgesics,
antipyretics, hormones & glucocorticoids if
entire gland is removed (given to prevent
crisis)

DI – for several days
◦ Tx: vasopressin
CSF leakage
 Visual disturbances
 Post-operative meningitis
 Pneumoencephalus (air in the
intracranial cavity)
 SIADH

◦ Hyposecretion of growth hormone by the
anterior pituitary gland causing
deficiencies in both the pituitary
hormones and the hormones of the target
glands.
◦ Causes
 Trauma
 Tumor  P.G. Or Hypothalamus (same
effect)
 Vascular lesion
 Surgery / radiation of pituitary gland
◦ Panhypopituitrism
 (Simmond’s disease)
 total absence of all pituitary secretions.
◦ Sheehan’s syndrome
 due to postpartum pituitary necrosis
 It occurs in women with severe bleeding;
hypovolemia and hypotension at the time
of delivery.
S/SX
 retarded physical growth
 premature aging  hair loss
 low intellectual development (slow)
 poor development of secondary sex
characteristics
 Hemianopsia / headache (if due to tumor)
 Weight loss, emaciation
 Hypometabolism
DIABETES INSIPIDUS
 Hyposecretion
of ADH &
deficiency of vasopressin
 Causes:
◦ Head Trauma, Brain tumor, ablation/
irradiation of Pit. Gland
◦ Nephrogenic  failure of kidney tubules
to respond to ADH (hypokalemia,
hypercalcemia)
S/Sx:
◦ polyuria of 4-24 liters/day  polydipsia
◦ s/sx of DHN dehydration
◦ Diluted urine (white-colored urine)  Sp. Gr. of
1.004 or less;
◦ fatigue, postural hypotension
◦ Constipation
Dx. Test:
 water deprivation test (no fluids for 4
to 18 hours  no increase in urine
concentration.
Management:
1. Replace ADH
Vasopressin replacement (desmopressin or DDAVP)
 Administered intra-nasally
 WOF  HPN, nasal congestion
Clofibrate  anti-lipidemic
 has an antidiuretic effect on clients with diabetes
insipidus.
Chlorpropamide (Diabenese) and thiazide diuretics 
potentiate the action of vasopressin.
 Enhances reabsorption of water in the kidney
promoting antidiuretic effect & regulates fluid balance
2. Adequate fluid replacement
monitoring I & O with specific
gravity
3. Provision of safe environment
especially with decreasing LOC,
 wear Medic-Alert bracelet
 Stimulates
melanocytes to
produce melanin
 Inhibited by dopamine
 Secreted during:
◦ fetal development
◦ early childhood
◦ pregnancy
◦ certain diseases