ENDOCRINOLOGY Ⅱ Pituitary Gland
Jan 05, 2016
ENDOCRINOLOGY Ⅱ
Pituitary Gland
Thyroid gland
Thyroid gland
The thyroid hormones Synthesis and secretion: epithelioid cells Storage: in colloid ,a large glycoprotein (thyrog
lobulin).
The thyroid hormones
The thyroid hormones
: combine with iodine
: 1mg/week
The thyroid hormones
The thyroid hormones
The thyroid hormones
When the synthesis of TH ceases, Physiologic effects of deficiency are not observed for 2-3 months
The thyroid hormones (TH)
The thyroid hormones
The thyroid hormones (TH)
Cretinism TH stimulation formation of dendrites,
axons, myelin and neuroglia Deficiency in iodine in fetus : TH↓→
Cretinism Treatment : supplement the TH within three
months after birth
The thyroid hormones (TH)
The thyroid hormones (TH)
The thyroid hormones (TH)
The thyroid hormones (TH)
Lengthy sleep
Nonpitting edema
The thyroid hormones (TH)
The thyroid hormones (TH)
Increase the appetite
:TH↓→constipation
HyperthyroidismHyperthyroidism
Major clinical signs :include weight loss (often accompanied by an increased appetite),anxiety, intolerance to heat, hair loss, muscle aches, weakness, fatigue, hyperactivity, irritability
The thyroid hormones (TH)
Regulation of Thyroid Hormone Secretion
Hypothalamic Pituitary Thyroid Axis Autoregulation
Regulation of Thyroid Hormone Secretion
Hypothalamic Pituitary Thyroid Axis
Cold, etc.
TRHhypothalamus
TSHAnterior pituitary
T3,T4
Target cell
Thyroid gland
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Regulation of Thyroid Hormone Secretion
Mechanism of goiter Iodine↓→T3,T4↓→
TSH↑ (negative feedback) →
T3,T4 ↑and thyroid cells ↑ →goiter
The thyroid hormones (TH)
Regulation of Thyroid Hormone Secretion
Auto regulation Wolff-chaikoff effect
Without control of TSH, the thyroid gland can adapt itself function to iodide uptake
Iodide concentration: 10mmol/L , no uptake of iodide
Regulation of Thyroid Hormone Secretion
Effect of Autonomic Nervous System on Thyroid Activity Sympathetic nerve: formation of TH↑ Para sympathetic nerve: formation of TH↓
Abnormality of thyroid gland Hypothyroidism
Cretinism: extreme hypothyroidism during fetal life, infancy, or childhood
Goiter Myxedema: bagginess under the eyes and swelling of
the face develop atherosclerosis Sleeping up to 12 to 14 hours a day, extreme muscular sluggishness heart rate↓ cardiac output↓ blood volume↓ Body Weight↑ Constipation mental sluggishness
Abnormality of thyroid gland Hyperthyroidism
high state of excitability intolerance to heat increased sweating mild to extreme weight loss varying degrees of diarrhea muscle weakness nervousness or other psychic disorders Extreme fatigue but inability to sleep tremor of the hands
Summary
thyroid hormones Function Abnormality regulation