Endocrine System Part 2 Flashcards
major actions of E/NE
- maintain plasma glucose
- maintain blood pressure
- increase HR and force of contraction
- bronchondilation
- BF distribution vs. vasoconstriction/vasodilation
- -increase metabolic rate
Quickest acting hormones
E/NE
-quickest acting hormones. activity starts within 5 seconds. max activity reached in 10-20 seconds. activity ends 1-5 minutes
Uses alpha adrenergic receptors
Norepinephrine
Uses beta adrenergic receptors
Epinephrine
training effects of E/NE?
- at sub maximal intensities, training blunts E/NE responses
- near or at maximal intensity, training enhances E/NE responses
Overtraining and E/NE?
E/NE become chronically high when overtraining
Endocrine Parts of Pancreas?
Islets of Langerhans
- alpha cells
- beta cells
- gamma cells
Which hormone is secreted by alpha cells
glucagon
Which hormone is secreted by beta cells
insulin
Which hormone is secreted by gamma cells
somatostatin
Insulin is stimulated by
hyperglycemia
Primary effects of insulin
- facilitate glucose entry into cells
- GLUT-4
Secondary effects of insulin
-promote fuel synthesis and storage
2 types of diabetes
Type I
Type II
Type I Diabetes
- sudden onset
- autoimmune disease, sometimes associated with viral infections
- little heredity link
- destruction of beta cells (little to no insulin produced)
- average onset 14 years-juvinele diabetes
- treated with daily insulin injections
Type II Diabetes
- gradual onset
- associated with obesity
- hereditity link
- “insulin resistance” usually high insulin levels
- average onset 40 years
- early stages treated with diet and exercise (lifestyle factors). drugs to increase insulin sensitivity may be used
3 main issues with diabetes
- increase blood problems
- increase metabolism of fats (increase use of fats)
- increase metabolism of (depletion of protein)
increase blood problems
- excreted in urine when > 180 mg/dl, polyuria
- lack of energy, hunger (polyphagia)
- blood vessel damage
- inflammation, increase Hb A1C
- platelet abnormalities
increase metabolism of fats (increase use of fats)
- ketone bodies: fruity breath odor; acidosis; ketonuria
- increase LDLs (artherosclerosis-MI, stroke)
- weight loss
increase metabolism of (depletion of protein)
- proteinuria
- atrophy, weight loss, lack of energy
- altered organ function
- –kidney failure, blindness, etc.
- immunosuppression-poor healing
glucagons
- stimulated by hypoglycemia
- acts to increase blood glucose
- increase with exercise
- trigger for exercise. release is SNS
what happens to insulin, glucagon, and blood glucose during exercise
insulin decreases, glucagon increases, while blood glucose remains steady.
- exercise up-regulates receptors for insulin on muscle tissue and down-regulates elsewhere, allowing glucose uptake where needed, but yet preventing energy sparing effects of insulin
- glucagon gradually increases which increases glucose availability, allowing you to maintain plasma glucose levels despite high energy demands of exercise
Testosterone-androgenic
androgenic: promotes male sexual characteristics
Testosterone-anabolic
anabolic: tissue building-increase protein formation in nearly all tissues
Anabolic and Androgenic both…
- both indirectly and directly through triggering GH release
- partly responsible for protein synthesis/retention and hypertrophy from resistance training
Testosterone and bone mass
although testosterone decrease with age, since men maintain equal to or more than 50% testosterone secretion throughout life, men have decrease incidence of osteoporosis
Body comp effects and Testosterone
responsible for increase musculature in males after puberty so males are leaner than females
Endurance Training Effects and Testosterone
- resting testosterone levels in trained subjects is usually on low end of normal range
- –but there is some high incidence of impotence noted, especially in endurance trained men
Testosterone is used as a ____ aid
ergogenic aid
Testosterone is used as an anti-aging drug
used as a “youth hormone” to increase muscle strength and vigor but with questionable results
Major estrogen
B-estradiol
Epiphyseal plate and estrogen
Estrogens cause epiphyseal plate closing. Women stop growing several years before men. They are shorter
Estrogen and Na+ and H2) retention and hypertension
- increase metabolic rate, but not as much as testosterone
- increase deposition of fat in breasts, subcutaneous tissue, buttocks, and things
- cause Na+ and H2O retention, especially during pregnancy resulting in fluid retention and possible hypertension
Female Athlete Triad
- disordered eating typically cited, but now mainly believed to occur in nearly any situation where ENERGY AVAILABILITY IS LOW (maybe particularly CHOs)
- decreasing estrogen causing abnormal menses (AMENNORHEA)
- which then leads to OSTEOPOROSIS
Stimuli for EPO
exercise and altitude are 2 common stimuli
effect of EPO
-stimulare erythropoiesis (RBC production) in bone marrow
EPO used as an ergogenic aid
- in endurance athletes to increase O2-carrying capacity
- illegal and dangerous
(EPO) blood glucose during sprint
E/NE cause liver to release more glucose than being used by cells. Muscle glycogen mainly fueling spring. So, blood glucose increase
(EPO) blood glucose during endurance exercise
blood glucose remains steady. liver’s glucose release closely matches muscle’s uptake until liver glycogen depleted. then, muscle glycogen and blood glucose get low and fatigue occurs
