Part 1 of day 2 Flashcards
stimulus
triggers a cell to secrete a chemical messenger
chemical messenger acts on
a target cell by binding to a specific receptor
signal transduction
the bound receptor triggers a series of events inside the cells, referred to as signal transduction, that elicit a response
signals transmitted to the nucleus
sue changes in gene expression
The signal and response are terminated
homostatisis
some disease are caused by persistent signaling without termination while others are caused by wearing of signals.
some drugs are designed to either inhibit single or strengthen/activate them
chemical messengers
small molecules or proteins
example: acetylcholine or insulin
endocrine pathway
secretory cells and target cells are distant and the chemicals messengers must travel through the blood
paracrine pathway
secretory cells and target cells are close proximity
autocrine pathway
the secretory cell is the target cell
endocrine systems example
steroids,
catelocholamines, insulin
Hypothoalamic pituitary adrenal (HPA) axis
endocrine system example
the stimuli for HPA are stress and light (circadian rhythm)
cortisol and catecholamines travel through the blood to their (many) target tissue.
light stress-hypothalamus - (corticotropin-releasing hormone (CRH))- pituitary gland- (ACTH)- adrenal grand which produces either cortisol or epinephrine and neropinephrine
insulin
example of endocrine system
insulin travels through the blood and acts on multiple tissue to regulate metabolism
target tissues respond to insulin in different ways to adapt to increased fuel taken in by eating (fed state).
eat-fed state-glucose concentration goes up- glucose is taken up into the pancrease- activates serious of gated ion channels - release of insulin in blood- acts metabolism organs (fat cells, liver, etc)
