The endocrine system IV Flashcards
What does the posterior pituitary gland not do regarding hormones?
Synthesize them
Which hormone is synthesised in the hypothalamus and secrete from the posterior pituitary gland?
Neuropeptides
What three factors can influence growth?
Genetics, environmental state and exercise
How many hormones are involved in controlling growth?
At least 12
What are some examples of hormones involved in growth?
Growth hormone, insulin growth factors (IGF), thyroid hormones, insulin, sex hormones and corsisol
What is a major stimulus of postnatal growth?
Growth hormone
What does growth hormone stimulate the liver to secrete?
IGF-1 (insulin growth factor 1)
What intracellular process can growth hormone stimulate?
Protein synthesis
What organs/body features can growth hormone affect?
Muscle, bones, adipose tissue
What about the liver can growth hormone affect?
Its growth and function
Why is GH stimulated during exercise?
It stimulates muscle growth
How does GH stimulate muscle growth during exercise?
Via the release if IGF-1
How does different types of exercise affect GH?
They will induce different GH responses
Difference in GH responses between young and middle aged men?
Young individuals have a higher responsiveness
What in the liver does growth hormone stimulate during exercise?
Gluconeogenesis
What, in adipose tissue, does growth hormone stimulate?
The conversion of triglycerides to FFA and glycerol
What does GH do to glucose during exercise?
Blocks entry into tissues
What is the consequence of the blockage of glucose into tissues?
Increased FFA oxidation
Differences between GH and insulin during exercise?
GH has the opposite response to exercise that insulin does
Which hormones are secreted as a result of the endocrine response to stress?
Cortisol is released from the adrenal cortex, epinephrine and norepinephrine are released from the adrenal medulla
Role of cortisol regarding (nor)epinephrine?
It permits their action on muscles and blood vessels
What is cortisol’s role during long-term fasting and exercise?
It promote glucose synthesis in the liver
What does cortisol do in adipose tissue?
Increases lipolysis
What is a diurnal cycle?
One that repeats every day
How does cortisol regulate the production of glucose and FA between meals?
It maintains the cellular concentration of metabolic enzymes required to produce them
What is the role of a catabolic hormone?
Acts in synergy with other hormones to increase the supply of energy to the working muscle
How are elite athletes levels of cortisol compared to the general population?
Higher
What hormones mediate the fight or flight response?
Epinephrine and norepinephrine
What are catecholamines important for?
Stress responses
How does epinephrine mediate the fight or flight response?
Increases heart rate & blood pressure
Increases peripheral vasoconstriction
Increases lipid breakdown
Increases glycogen–> glucose
Increases coronary and bronchial dilation
How does norepinephrine respond to stress?
Increases heart rate and blood pressure and peripheral vasoconstriction
What % of the catecholamine secreted by the medulla is epinephrine?
80
How are norepinephrine and epinephrine linked?
Norepinephrine is a precursor of epinephrine
