pituitary thyroid

parathyroid

adrenal

pineal glands

1. regulate organic metabolism and water and electrolyte balance
2. adapt body to stressful situations
3. promote smooth sequential growth and development
4. control reproduction
5. regulate RBC production
6. w/ autonomic nervous system, control and integrate both circulation and the digestion and absorption of food

amino acid

steroids (lipophic)

based hrmones

second messenger

water soluble

ex. amines, thyroxine, peptides, and proteins

synthesied from cholesterol

gonadal and adrenocortical hormones

lipid soluble

directly interact with inside the cell

1. hormone (first messenger) binds to receptor
2. receptor activates G protein
3. G protein activates adenylate cyclase
4. adenylate cyclase converts ATP to cAMP (second messenger)
5. cAMP activates protein kinases

Epinephrine

ACTH

FSH

LH

Glucagon

PTH

TSH

Calcitonin

The process fo intracellulare receptors and direct gene activation

(steroid hormones and thyroid hormone)

1. diffuse into their target cells and bind with intracellular receptors
2. receptor-hormone complec enters the nucleus
3. receptor-hormone complex binds to a specific region of DNA
4. this prompts DNA transcription to produce mRNA
5. the mRNA directs protein synthesis

Target cell activation depends of

(3)

1. blood levels of the hormone
2. relative number of receptors on or in the target cell
3. affinity of binding between receptor and hormone

target cells form more receptors in response to the hormone

target cells lose receptors in response to the hormone (target cell desensitized)

Hormones are removed from the blood by:

(4)

1. degrading enzymes
2. kidneys
3. liver
4. half-life

Hormones are synthesized and released in response to:

(3)

1. humoral stimuli
2. neural stimuli
3. hormonal stimuli

changing blood levels of ions and nutrients directly stimulate the secretion of hormones

ex. declining calcium concentration stimulates PTH release. cases calcium to rise. stimulus is then removed.

nerve fibers stimulate hormone release

sympathetic nerouse system fibers stimulate the adrenal medulla to secrete catecholamines (epenephrine and norepinephrine)

under severe stress the hypothalams and the sypathetic nervous system are activated - as a result, body glucose levels rise

this is an example of what

pituicytes and nerve fibers

glandular tissue

hypothalamus and posterior pituitary

oxytocin and ADH are stored in __________________ in the posterior pituitary and are released when hypothalamic neurons fire

primary capillary plexus

portal veins

secondary capillary plexus

children = giantism

adults = acromegaly

TSH secreted from anterior pituitary stimulates thyroid hormone secretion by thyroid gland, also maintains structural integrity of thyroid gland

example of

tropic hormones

-regulates hormone secretion by another endocrine gland

TSH is stimulated by_________________;

inhibited by _________

TRH

rising blood levels of thyroid hormones that act on the pituitary and hypothalamus

FSH - stimulate gamete production

LH - promotes production of gonadal hormones

Thyroid hormone plays a rold in:

(5)

1. maintenance of blood pressure
2. development of skeletal and nervous systems
3. reproductive capabilities
4. stimulates RBC formation and thus enhances oxygen delivery

hyposecretion = autoimmune disease (graves)

hyposecretion (adults) = myxedema or endemic goiter

hyposecretion (infants) = creitinism

increases absorption of calcium by the intestinal mucosa; rising Calcium in the blood inhibits ___ release

children = rickets

adults - osteomalacia

mineral corticoids

glucocorticoids

sex hormones

Regulate electrolytes in ECF

ex. aldosterone

released in response to ACTH, patterns of eating and activity, and stress; maintain blood pressure by increasing the action of vasoconstrictors

ex. cortisol

Hyposecretion of glucocorticoids

Chromaffin cells secrete what?

causes blood glucose to rise, blood vessels to constrict, hear rate increase, blood to be diverted to the rain, heart and skeletal muscles

characterized by lack of insulin secretion

destruction of B cells

characterized by normal or even increased insulin secretion but reduced sensitivity of insulin's target cells

onset - adulthood