PHYL2001 Final: PHYL2001 Revision Endocrine System
PHYL02001 Revision: ENS
Hormones:
-Steroid hormones vs peptide hormones
-Tyrosine - small molecules -> dopamine, adrenaline, thyroxine
Endocrine signalling:
THE HYPOTHALAMIC-HYPOPHYSEAL SYSTEM
-brain release hormones, then cascade of hormones to the body that control the body
Hypothalamus and pituitary gland (hypophysis) = conductor of endocrine orchestra
Information (afferent) pathway:
-Sensory information to CNS, hormones from body + emotions
-impact hypothalamus (whatever sent here can be sent back to CNS)
-direct hormonal release to pituitary gland
-(nerves can release hormones at nerve endings called neuroendocrine)
-Onto target
Infundibulum
-= stalk between hypothalamus and pituitary gland
-(surrounded by both anterior and posterior pituitary)
-= whole thing surrounded by skull
Hypothalamus
-Posterior: has arterial blood supply coming in and venous supply leaving
-(any hormone released can go to heart and rest of body)
-the nerve endings in the capillary net, instead of releasing nt, release HORMONE through
vesicle -> capillaries -> body
2 main hormone released: by posterior PG
-Oxytocin
-Vasopressin (ADH)
Oxytocin (breastfeeding)
-breast myoendothelial cell
-Baby suckles, stretch receptor activated
-sensor nerves sends information to brain
-feeds information to hypothalamus to neurons
-electrical messages down to posterior
-oxytocin go through bloodstream to breast myoendothelial cell, contract, milk pushed through
duct out of nipple into baby’s mouth
-Emotions can feed into this system too (can cause milk to eject also)
-Whole things squashes down, pressure, milk comes out
Posterior PG
-is part of gland (neuron bodies in brain), but APG separate
-it has arterial blood supply at hypothalamus called median eminence
-blood stream in APG (filled with cells)
-Enter venous circulation to rest of body
Document Summary
Tyrosine - small molecules -> dopamine, adrenaline, thyroxine. Brain release hormones, then cascade of hormones to the body that control the body. Hypothalamus and pituitary gland (hypophysis) = conductor of endocrine orchestra. Sensory information to cns, hormones from body + emotions. Impact hypothalamus (whatever sent here can be sent back to cns) (nerves can release hormones at nerve endings called neuroendocrine) = stalk between hypothalamus and pituitary gland. (surrounded by both anterior and posterior pituitary) Posterior: has arterial blood supply coming in and venous supply leaving. (any hormone released can go to heart and rest of body) The nerve endings in the capillary net, instead of releasing nt, release hormone through vesicle -> capillaries -> body. Oxytocin go through bloodstream to breast myoendothelial cell, contract, milk pushed through duct out of nipple into baby"s mouth. Emotions can feed into this system too (can cause milk to eject also) Whole things squashes down, pressure, milk comes out.
