Endocrine System (exam 3)

Endocrine System

- glands that produce hormones

- secretes into blood stream

(ex; prolactin (made by anterior pituitary gland) -> mammary glands

Anatomy of Hypothalamus & Pituitary Gland

- hypothalamus = controller of entire endocrine system

F: release hormones that control the release of other hormones

hypothalamohypophyseal portal system

- capillary-vein-capillary

- concentration stays really high

- doesn't need to be washed over entire body

- only for anterior pituitary gland (adenohypophysis)

neurons

- only for posterior pituitary gland (neurohypophysis)

- neurons w/ hormones at synapse

- not neurotransmitters

- release proteins (ex; oxytocin) -> capillary bed

Thyroid Gland

- responds to TSH, which comes from adenohypophysis

- releases thyroid hormone

F: regulates metabolism

Thyroid Gland

- made of simple cuboidal ET, which make hormone

- makes follicles & in the middle fills up w/ TH

Parathyroid Gland

- 4 small glands on the back of thyroid

- release parathyroid hormone

- which increases Ca2+ blood levels

- activates osteoclasts (break bone down)

- active if not eating enough Ca2+ in diet

Adrenal Gland

- sit on top of kidneys (2 glands)

(1) adrenal cortex

- releases steroid hormones (ex; cortisol = stress)

(2) adrenal medulla

- releases adrenaline (epinephrine)

Pancreas

- pancreatic duct -> (alveolar) pancreatic acini(us)

- releases a digestive enzyme (part of digestive sys)

islets of langerhans

- releases insulin -> decrease blood glucose levels

(ex; after eating, release insulin to absorb glucose)

Clinical Condition

- Goiter

- enlarged thyroid gland b/c lack of iodine

- can't make TH, but is still receiving signals from hypothalamus

- need to release TH, dependent on it

- continues to be stimulated & it gets bigger