SAM Pathway Flashcards
What does the acronym in SAM Pathway stand for?
Sympathetic Adrenal Medulla
During Stress when does the SAM pathway activate?
How long for peak response to occur?
Immediately
Minutes to Hours
What type of communication is there between SAM and HPA axis?
Bidirectional Communication
During Bidirectional Communication
SAM can contribute to _ _ _ secretion
GC can regulate secretion of _ from _ _
Adrenal Cortex Glucocorticoid
Catecholamine Adrenal Medulla
What does SAM axis initiate?
This involves changes to _ and _ function
These change affects what?
Flight, Fight, Freeze
Neuroendocrine, Immune
Metabolism, Cardiovascular, Behaviour, Respiration, Disease Resistance
- _ is released from _ _ _ that innervate the _ _ via _ _
Ach, Sympathetic Nerve Fibers, Adrenal Medulla, Splanchnic Nerve
- _ binds to _ on _ _ cells which triggers secretion of vesicles containing _ and _ into circulation
Ach, NiAchRs, Adrenal Chromaffin, NEPI, EPI
What is the primary source of basal and stress induced EPI?
What about Circulating NEPI?
Adrenals
Other Tissue
Catecholamines mediate their physiological responses via _ and _-specific expression of _ and _ _
Tissue and Cell-Specific
Alpha and Beta Receptors
Basal concentrations of Circulating Catecholamines vary based on what?
Why?
Time of Day and Season
Catecholamines are under the influence of hormones like melatonin, ACTH, GC, gonadal steroids
Melatonin is produced by what?
Pineal Gland
ACTH is produced by what?
Anterior Pituitary
GC is produced by what?
Adrenal Cortex
EPI & NEPI Production
EPI & NEPI are synthesized by _ _ cells
NEPI is converted to EPI using the enzyme _
Adrenal Chromaffin
PNMT
Synthesis of EPI Pathway
L-Tyrosine (Tyrosine Hydroxylase)
L-DOPA (Aromatic L-AA Decarboxylase)
Dopamine (Dopamine B-Hydroxylase)
NEPI (PNMT)
EPI
Catecholamine Synthesis Regulation
Enzyme activity & Expression Levels (PNMT)
Plasma Binding Proteins
Short Half Life due to enzymes deactivation
Tissue Specific expression of a and B adrenergic receptors
