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Pancreatic and Adrenal Hormon

Topics for today:

¥Action of parathyroid ¥Review of pancreatic ¥Actions of adrenal cortex hormones ¥Adrenal cortex disfunction ¥Actions of adrenal medulla hormone ¥Hormone control of organs

Parathyroid hormone

Parathormone - a hormone

effects of parathormone:*

¥ increased plasma level ¥ increased calcium mobilization from bon ¥ induced Ca absorption in GI tract ¥ increasedreabsorption Ca from tubules

*effects opposite

1 Pancreatic hormone effects

Insulin - peptide hormoneGlucagon - peptide hormon - associated‘fed’ with state - associated‘fasted’ with st effects of : effects glucagonof :

¥lowers ¥increases blood glucose ¥promotes ¥stimulates by brea muscle & ¥stimulatesgluconeogenesis ¥stimulatesglycolysis and glycogen synthesis ¥stimulates storage of ¥stimulates synthesis

GLUT-4 recruitment

GLUT-4 cycles between plasma membrane and intracellular vesicles containing the . Increased insulin causes rapid cycling to plasma membrane, resulting in 10- to 30-fold increase in glucose uptake.

Insulin levels during absorptive and postabsorptive states

AbPost-Ab Ab Post-Ab

relative hormone levels plasma glucose level insulin

time, hr

2 Insulin changes in exerc Insulin level decreases during Plasma insulin 0

-25

-50

Percent change -75

-100 25 50 75 100

Percent VO2 max

Exercise increases insulin sensitivity such that fewer insulin receptors are needed.

Glucagon levels during absorptive and postabsorptive states

AbPost-Ab Ab Post-Ab

&

relative hormone levels plasma glucose level insulin

time, hr

Hormones of adrenal cortex

zona glomerulosa zona fasiculata zona reticularis

CH 2OH HO C=O O C Mineralocorticoids -

¥ increased reabsorptionrenal of sodium O aldosterone ¥ increased renal of potassium ¥ increased plasma volume & blood pressure ¥ secretion triggered by potassiumangiotensin II&

3 Hormones of adrenal cortex

zona glomerulosa CH 2OH zona fasiculata C=O zona reticularis HO OH

O cortisol

Glucocorticoids - cortisol¥ increasedgluconeogenesis Ð use ¥ increased plasma glucose levelamino acids—> glucose ¥ increased lipid mobilization¥ degradation of glycog ¥ anti-inflammatory release of glucose ¥ immunosuppresive ¥ output increases during sle periods fastingof

Hormones of adrenal cortex

zona glomerulosa

zona fasiculata O zona reticularis

HO dehydroepiandroster AndrogensÐ ¥ increased protein synthesis DHEA is weak with ¥ masculinizing effects in almost no effect in male bu femalehypersecretion ( ) masculinizing effects in femal

Adrenocortical disfunctions

Cushing’s syndrome Ð excessive productioncortisol of resulting in loss of muscle protein

Addison’s disease Ð insufficent productioncortisol of and aldosteronecausing cardiac disturbance due+ to e

Adrenogenital syndrome Ð excessive production of a resultingvirilization in in female

4 Adrenal medulla (interior)

¥ Composed of modified post-syna sympathetic neurons ¥ Releases mostlyepinephrine . ¥ Has effects similar to those t by sympathetic nervous system

Adrenal medulla hormones

HO

HO -CH-CH2 - N-CH3 OH H

Effects of epinephrine: ¥ causes elevated blood glucose level ¥ stimulatesglycolysis & use ¥ increases cardiac output & blood pre ¥ shifts blood flow to ¥ increases rate and depth of respirat

Organ responses to Epinephrine

Causes glycogen Causes fatty acid rele degradation in muscle from adipose tissue

fatty glycogen acids trigly- cerides

lactate

muscle lactate adipose tissue

Causes release ofglycogeno lysis glucose from liver glucose ...elevated plasma leve liver

5 Hormone action time

Epinephrine is in group offast-acting hormones

Fast-acting Hormones Slow-acting Hormones

¥ ¥ Throxine ¥ Epinephrine ¥ Cortisol ¥ Insulin ¥ ¥ glucagon ¥ ¥

Topic for Wednesday:

Gonadal Hormones

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