Anatomy and basics Flashcards
what is a hormone
to excite
what does endocrine mean
within/ separate
what does exocrine mean
outside-
three types of hormone action
endocrine
paracrine
autocrine
endocrine hormone action involves ?
blood borne- acting at distant sites
paracrine hormone action involves ?
acting on adjacent cells
autocrine hormone action involves ?
feedback on the same cell that secreted the hormone
properties of water soluble hormones
unbound
bind to receptor surface
short half life
fast clearance
peptides, monoamines
properties of fat soluble hormones
protein bound
diffuse into cell
long half life
slow clearance
thyroid hormone and steroids
characterisitcs of peptide hormones
vary in lentgh
linear or ring structure
stored in secretory granules
released in pulses
characteristics of thryoid hormones
protein bound
20% of T3 in circulation
hormone receptor locations?
cell membrane
cytoplasm
nucleus
characteristics of cholestrol and steroid hormones
fat soluble
enters cells directly to nucleus to stimulate mRNA production
transported by vit d binding protein.
describe steroid action of hormones
Steroid hormone diffuses through plasma membrane and binds to receptor
Receptor-hormone complex enters nucleus
Receptor-hormone complex binds to GRE
Binding initiates transcription of gene to mRNA
mRNA directs protein synthesis
5 methods to control the action of hormones
- hormone metabolism
- hormone receptor induction
-hormone receptor down regulation
-synergism
-antagonism
what could a tumour on pituatary gland cause
would press on the optic chiasm
may cause bi temporal hemianopia
less severe- double vision
function of the thyroid hormone
Accelerates food metabolism
Increases protein synthesis
Stimulation of carbohydrate metabolism
Enhances fat metabolism
Increase in ventilation rate
Increase in cardiac output and heart rate
Brain development during foetal life and postnatal development
Growth rate accelerated
signs of pituitary dysfunction
tumour mass effects
hormone excess
hormone deficiency
define is appetite
desire to eat food
define hunger
a need to eat
define anorexai
lack of appetite
define satiety
feeling of fullness
risk of obesity
Type II diabetes
Hypertension
Coronary artery disease
Stroke
Osteoarthritis
Obstructive sleep apnoea
Carcinoma
what does weight regulation depend on
genes
environment
homeostasis
what part of the brain plays a central role in appetite regulation
hypothalamus
role of leptin
hunger supression
role of ghrelin
hunger initiation
what would happen if you didnt have leptin
wouldn’t stop eating
what does peptide yy do
binds to npy receptors
inhibits gastric motility
reduces appetite
