Rutgers - Biology 2 - Endocrine 2

Endocrine responds directly to Stimulus

Stimulus is received by sensory nerve first

Hormones → bloodstream → binds to TC and specific receptor → response

Neurosecretory cell stimulated → neurohormones → bloodstream → TC and receptor → response

pH control

Regulation of milk release

Receives information from the nerve.
Coordinated regulation of hormones
Signal Pituitary
Hypothalamus

Neuroendocrine

Tropic and nontropic: RH (releasing hormone) and IH (inhibiting hormones), ADH (vasopressin), Oxytocin

Death

Stores and secretes hormones

Neuroendocrine

ADH (Vasopressin)
- Acts on kidney
- Triggers water conservation
- Osmotic homeostasis
Oxytocin
-milk
-contractions
-care
-bonding

-Kidney failure
- Mammary gland problems

Synthesizes and secretes hormones.

Neuroendocrine

Stimulating hormones

Metabolism
BP, Muscles tone, heart rate
regulates digestive and reproductive function

Endocrine

TRH (Thyroid Releasing Hormones)
TSH (Thyroid Stimulating Hormones)
T3 (Tr-Iodo-Thyronine)
T4 (Thyroxine)

- Goiter: low dietary iodine or abnormally high TSH
- Hypothyroidism: weight gain, low metabolism, low bp, and cold
- Hyperthyroidism: weight loss, high metabolism, high bp, and hot
- Grave's disease: autoimmune disease (overstimulation of TSH receptors)

Control blood Ca2+ levels

Endocrine

PTH (Parathyroid Hormone)

High or low Ca2+ levels Hypersecretion: causes osteoporosis

- Flight or fight or freeze response
-Short-term response to stress (regulates metabolism, blood, glycogen, and O2 delivery)
- release quickly, wear out fast

Neuroendocrine

-epinephrine (adrenaline)
-norepinephrine

No flight or fight response

Chronic stress

Endocrine

- Glucocorticoids: non-carb glucose that breakdown muscle (lowers immunity)
- Mineralocorticoids: maintain salt and water balance and increase blood volume
- Corticotropin-releasing factor (CRF):
- Stimulate Ant. Pit.
- Release Adrenocorticotropic Hormone (ACTH)

Anxiety disorder

If the hypothalamus signals Post. Pit.
1. Hormones produced in hypothalamus
2. Travel down long axons
3. Stored in Post. Pit.
4. Released in response to nerve signals If hypothalamus signals Ant. Pit. - Hormones (RH or IH) sent via the pituitary portal vein to specific cells in Ant. Pit.

1. Levels of thyroid drop below normal.
2. Hypothalamus → TRH
3. Ant. Pit. → TSH
4. Target tissue (thyroid) → T3 and T4
5. Levels of thyroid return to normal

When blood Ca2+ is low -
Parathyroid releases PTH → signals bones, kidneys, and liver to release Ca2+
When blood Ca2+ is high - The thyroid releases calcitonin → signals bones and kidney to take in Ca2+

Adrenal Medulla - Hypothalamus → Post. Pit. → Adrenal Medulla → epinephrine or norepinephrine
Adrenal Cortex - CRF → stimulates Ant. Pit. → releases ACTH → Adrenal Cortex → glucocorticoids and mineralocorticoids

Hormones → bloodstream → binds to TC and specific receptor → response

Neurosecretory cell stimulated → neurohormones → bloodstream → TC and receptor → response