Introduction to the Endocrine System Flashcards
Autocrine
Paracrine
Endocrine
Neuroendocrine
- secretion affects self or cell of similar type
- secretion affects neighbor cell
- secretion affects target further away (via bloodstream)
- Neuron itself releases secretion into bloodstream
What are special endocrine cells and hormones?
Some cells are within organs (like adipose, heart etc.) and release hormones
-some hormones get converted in the bloodstream (e.g. angiotensin II and vitamin D)
Draw out what hormones the hypothalamus, anterior, posterior pituitary, thyroid and parathyroid glands release
Ok
Draw out the products of the various endocrine glands
Ok
Properties of peptide/protein hormones
Protein is >100 amino acids long
Water soluble
Membrane receptor
Stored in vesicles
Properties of steroid hormones
Precursor is cholesterol
Lipid soluble
Nuclear receptors
Properties of amine hormones
Derived from tyrosine (can be water or lipid soluble)
Describe how protein/peptide hormones are created
Preprohormone (not functional) > ER (turned to prohormone) > vesicle packing and release > cleaved to functional hormone
How are hormones released from storage?
Intracellular Ca2+ increase > cAMP and PKA activation > vesicles with hormone released into bloodstream
Structure of the steroid hormones
4 rings structure (like cholesterol)
Modified side chains
Which glands produce steroid hormones?
Adrenal cortex, gonads, Placenta, corpus luteum
*AC and reproductive organs
What are the two groups of amine hormones?
Catecholamines
Thyroid hormones
What are the properties of catecholamines? What hormones are catecholamines?
- made in cytosol granules. Targets are on membrane
- Epinephrine/norepinephrine and dopamine
What are the properties of thyroid hormones?
- stored in gland lumen as thyroglobulin
- target nuclear receptors
Broadly,at what level are hormones regulated?
Synthesis, secretion or circulation
How does hormone protein binding correlate with hormone half life?
Higher binding = higher half life = lower clearance rate