Ch 17- Endocrine System Flashcards
Endocrinology
study of the endocrine glands
hormone
chemical messenger secreted by cells into the interstitial fluid that diffuses to the blood capillaries and transported into the bloodstream to target cells and binds to receptors that effects the cells activity
organs with endocrine tissue
hypothalamus, pancreas, ovaries, testes, kidneys, heart etc
Endocrine glands
pituitary, thyroid, parathyroid, adrenal and pineal glands
tropic hormone
hormones that act on other endocrine glands/tissues
-chain reaction
-eg hypothalamus act on pituitary gland
functions of a hormone
-regulate reproductive organs
-energy balance
-biological clock (melatonin)
-contraction of smooth and cardiac muscle
-growth, repair and development
Nervous vs endocrine systems
mediator- N neurotransmitters E hormones
action site- N synapse E anywhere
target cells- N neurons E any cells
duration- N short E long
Hypothalamus and Pituitary relationship
The hypothalamus sends nerve impulses to the posterior pituitary lobe through the pituitary stalk
pituitary gland location
sits within the sella turcia and sphenoid bone
-attached to hypothalamus
posterior pituitary
-grows downward from the brain
-two hormones only
-stores/ controls hormones in hypothalamus
anterior pituitary
-grows upwards
-larger portion of pituitary gland
-produces hormones that regulate growth, metabolism, reproduction, and stress response
Lipid-soluble hormones
-need transport protein (2nd msg)
-thyroid hormones
-steroid hormone (testosterone and cortisol)
-no amplification (slower)
wate-soluble hormones
-in solution no transport protein moves freely
-peptide hormones (oxytocin, insulin)
-majority of hormones
-amplification (rapid response)
which has water and fat solubles?
tryptophan- melatonin
hormone secretion control
-hormonal (most comm) tropic hormones
-humoral- in response to blood levels
-neural- fight or flight
lipid soluble 2nd messaging system
-hormone binds to receptor
-adenylate cyclase activates cAMP (2nd messenger)
-cAMP produces kinase
-activated enzymes has range of effects on cell
names of 3 G’s to promote glycogen breakdown
glycogenesis- synthesis of glycogen
glycogenolysis- breakdown of glycogen with addition of water
gluconeogenesis- creation of new glucose
hypoglycemic vs hyperglycemic
hypo: blood glucose down, insulin, thyroid, increase use of glucose and moves into cells
-Hyper: blood glucose up, glucagon, human growth hormones, cortisol
signs a symptoms of diabetes
-polyuria- urine
-polydipsia- excessive thirst
-polyphagia- hunger
-hyperglycemia (T2)
-decrease in insulin
complications of diabetes
-damage to retina
-damage to kidneys
-damage to peripheral nerves
-poor wound healing and ulcers
-early heart attacks
-can be life threatening
3 stress phases
-alarm- flight or flight, increase sweat gland secretion, increase in heart rate
-resistance- cortisol, coserves glucagon, elevation of blood
-exhaustion- depleted all resources, fatal w out intervention
Local and circulating hormones
-local- autocrine targets itself, gap junction, paracrine targets nearby cell
circulating- most endocrine cells
5 releasing hormones from the
hypothalamus (tropic)
-GnRH- gonadotropin rel horm
-GHRH- growth horm rel horm
-TRH- thyrotropin rel horm
-CRH- corticotropin rel horm
-PIH- prolactin inhibit horm
-somatostatin
7 anterior pituitary hormones
PRL- Prolactin
TSH-Thyroid stimulating hormone
LH- Luteinizing hormone
FSH-Follicle-stimulating hormone
GH- Growth hormone
ACTH- Adrenocorticotrophic hormone
MSH- Melanocyte-stimulating hormone
