Monday, 19 SeptemberChapter 11 The Endocrine System

King DS, Sharp RL, Vukovich MD, Brown GA, Reifenrath TA, Uhl NL, Parsons KA . Effect of oral androstenedione on serum testosterone and adaptations to resistance training in young men: a randomized controlled trial. JAMA 1999; 281(21):2020-8

Two 1QQs returned on PianoLab this week: Analyzing a research paper + First Endocrine Case study.Lab next week: Four more cases in endocrinology

Pick up your photocopy from the Piano, read it before lab!

Wednesday, 21 SeptemberChapter 6 The Nervous System

Read sections A and B

1QQ # 6 for 8:30

1. TSH stimulates

a) The thyroid gland to take up iodide

b) the synthesis and secretion of thyroglobulin

c) The uptake of thyroglobulin from the colloid

d) Follicular cells of the thyroid gland to grow

e) The hypothalamus to secrete more TRH. OR

2. In response to a drop in blood pressure

a) Juxtaglomerular cells of the kidney secrete less renin

b) Elevated levels of aldosterone stimulate thirst

c) Newly-formed angiotensin I causes vasoconstriction

d) Elevated levels of aldosterone promote Na+ retention by the kidneys

e) The liver produces more Angiotensin II.

Write the number of the one question you choose to answer.

1QQ # 6 for 9:30

1. TSH stimulates

a) The thyroid gland to take up iodide

b) the synthesis and secretion of thyroglobulin

c) The uptake of thyroglobulin from the colloid

d) Its target cells to incorporate more Na+/K+ ATPase into their membranes

e) The hypothalamus to secrete more TRH. OR

2. In response to a drop in blood pressure

a) Juxtaglomerular cells of the kidney secrete less renin

b) Elevated levels of Angiotensinogen stimulates thirst

c) Newly-formed angiotensin I causes vasoconstriction

d) Elevated levels of aldosterone promote Na+ retention by the kidneys

e) The liver produces more Angiotensin II.

Write the number of the one question you choose to answer.

Fig. 11.12a

Receives inputfrom manyregions ofbrain; many factorsAffect its functionHomeostatsis center.

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Fig. 11.12b

Vasopressin (= Antidiuretic hormone)Oxytocin

NeurohypophysisAdenohypophysis

6

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Tropic hormones control the function

Trophic hormones promote survival and growth of targets

Releasing Hormone

Release-inhibiting Hormone

Hypothalamo-hypophyseal portal system

A

A

S S

P

P

PPPPP

PPPP

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Tropic hormones control the function

Trophic hormones promote survival and growth of targetsReleasing Hormone Release Inhibiting Hormone

Long

-loop

neg

ativ

e fe

edba

ck

Sho

rt-lo

op N

eg. F

eed.

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Who Cares?

• Symptoms of hypothyroidism

• Levels of TSH and TH?

• Explain enlarged thyroid gland

• Cause: Inadequate dietary intake of iodine

• Treatment?

EndemicGoiter

TRH

TSH

T3 & T4

Goiter

Elevates basal metabolic rate,potentiates response to EPI

If hypothyroid during pregnancy…cretinism = congenital hypothyroidism

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Classification of Endocrine disorders

•Hypersecretion– Primary– Secondary

•Hyposecretion– Primary– Secondary

CRH

ACTH

Cortisol

hypothalamus

Anterior pituitary

Adrenal Cortex

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Who else Cares?

Aunt Dot S 5

T3 and T4 from Thyroid gland

TSH from Ant. Pit.

TRH from Hypothal.

⇧Metabolic rate

⇧Temperature⇧sensitivity to EPI (up-regulation of adrenergic receptors)

⇧Heart rate and ⇧Blood Pressure

⇧Lipolysis and fuel mobilization Weight loss

The cause: Abnormal Immunoglobulins in patient activate TSH receptors on Thyroid cells

⇩

⇩

Grave’s Disease

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Blood test:TSH levels lowTH levels high

Grave’s Disease

Treatment:Radioactive IodineMechanism:……..

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⇧Cortisol secretion from Adrenal Cortex

Mobilize fuel from muscle & adipose tissueSuppress non-essential functions (reproduction & growth)Suppress inflammatory &immune responsesPotentiates response to EPI (vascular smooth muscle)

ACTH from Ant. Pit

CRH from Hypothalamus

Physical traumaProlonged exposure to coldProlonged intense exerciseInfectionSleep deprivationPainFrightEmotional distress

Vasopressin

Cytokines fromimmune cells

Excess Cortisol from 1) adrenal cortex tumor (primary) or 2) hypersecretion of ACTH from anterior pituitary (secondary)

Cushing’s Syndrome

Basal levels of CortisolRequired for normal sensitivity to EPI; symptoms of excess cortisol are…..

Clinical example: treatment of chronic inflammation (e.g. arthritis) can lead to Cushing’s Syndrome!

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