Unit 3: Chapter 5 Flashcards
Objective Questions?
Localized regulatory factors lead to _____ responses.
physiologic
(cells, tissues, organs)
What are the roles of hormones?
Chemical messengers
What is endocrinology?
The study of hormones and their effects on the body.
Hormone production is affected by exercise and other stressors.
Endocrine systems hormones are most responsible for homeostatic maintenance and following__.
exercise
What is exercise?
Structured repetitive movement
What are some physiologic processes hormones control? How is it achieved?
The regulation of macronutrient fuel stores
“Fight or flight” response
The adaptive response to exercise and maturation
Achieved through cell signaling
Neuroendocrinology
The study of the physiology of the control systems
Studies the roles of nervous and endocrine systems
The ____ system and ___ system encompass the two major homeostatic systems in the control and regulation of various functions: ______
Nervous; endocrine
Functions:
—Body temp
—Metabolic regulation
—Cardiovascular
—Renal
—etec
What is the neuroendocrine response?
Both systems (nervous and endocrine) sense physiologic stressors, organize a response, and deliver messages to organs or tissues.
How do the systems differ in the message delivery?
Endocrine system—Hormones—(Slow)
Nervous System—Neurotransmitters (Fast)
What are the classes of Hormones?
Amino Acid derivates
peptides
proteins
steroids
(Through blood)
Blood hormone concentration:
Effect a hormone exerts on a tissue—A proportional to: ___ & ______
Hormone concentration in the plasma and;
the number of active receptors
Plsama Concentration depends on:
1) the hormone secretion rate
2) The rate of hormonal metabolism or exercising
3) Transport protein quantity (for lipid-based hormones)
4) Changes in the plasma volume
Control of hormone secretion:
Rate of secretion of hormone from endocrine ……….
What are two Factors that influence the secretion of hormones from the endocrine gland?
- Magnitude of input
- Stimulatory versus inhibitory input
Rate of metabolism or exertion of hormone:
Is it active or Inactivate near receptor?
Where is it metabolized from?
Inactive;
Liver + Kidneys
Quantity of transport proteins
What do steroid hormones and thyroxine bind to?
Bind to plasma proteins.
Changes in plasma volume are ___ proportional to changes in the hormone concentration.
inversely
What 3 factors affect blood hormone concentration?
- Capacity. (maximal quantity for a hormone to bind to transport protein)
- Affinity (the chemical tendency for a hormone to bind to transport protein)
- Increased Capacity and increases affinity. (reduced amount of free hormones
What can hormones affect?
Hormones only affect tissues that contain specific hormone receptors.
What is downregulation
Receptor # decreases when hormone levels are elevated.
What is up-regulation
Increase in receptor # when there are low lvls of hormones.
What are the actions of hormones?
- Activation of genes (DNA), AKA PROTEIN SYNTHESIS
- Activating second messengers through G protein
(Ex. Cyclic AMP).
(G protein links hormone receptors from in and
outside of the cell) - Altering membrane transport.
(Carrier molecules) (INSLUIN)
What Do the hypothalamus, Anterior Pituitary Gland, and Posterior Gland do and secrete?
- Hypothamalus
—Controls secretion - Anterior Pituitary Gland
—All of them
—ACTH. (Adrenocorticotropic hormone)
—FSH. (Follicle-stimulating hormone)
—LH (Luteinizing hormone)
—MSH. (Melanocyte-stimulating hormone)
—TSH (Thyroid-stimulating hormone)
—GH (growth hormone) - Posterior Pituitary Gland
—Oxytocin
—(ADH) antidiuretic hormone
…………
What is oxytocin?
What stimulates growth hormones?
Hypertrophy training—Stress training
(Alt. Restriction of blood flow)
What is Antidiuretic hormone (ADH)?
What is another name?
What does it do?
What stimulates ADH?
aka, vasopressin
Reduces water loss from the body to maintain plasma volume
Exercise Stimulates it
What are thyroid hormones?
Calcitonin
Lowers Calcium
Blocks Ca++ release from bone, decreases osteoclast activity,
stimulates excretion by kidneys lowers plasma Ca++
AP Triiodothyronine (T3 ) and thyroxine (T4
parathyroid
What does the adrenal medulla secrete?
Secretes the catecholamines
Epinephrine (E) and norepinephrine (NE)
What are Epinephrine (E) and norepinephrine (NE)?
What does the adrenal cortex secrete?
Secretes steroid hormones that come from cholesterol.
Aldosterone Cortisol Androgens and estrogens
……
Is muscle or adipose tissue Endocrine Glands?
Yes
What hormone does fat secrete?
What does it do?
Leptin
—Suppresses appetite = when you’re full
—Enhances insulin sensitivity and fatty acid oxidation = the breakdown of fats
Adiponectin
— Enhances insulin sensitivity and fatty acid oxidation
With increased fat mass (obesity), Higher ___ levels and lower ____ levels.
The hormones don’t do what its supposed to do, which leads to obesity.
Leptin; adiponectin
____ drops your plasma levels
Exercise
TABLE 5.2 Summary of Hormonal Responses
What hormones are secreted from the pancreas?
The pancreas has different cells that secrete hormones.
Insulin
Glucagon
Somatostatin
Does the pancreas function as an exocrine or an endocrine function?
BOTH;
it dumps and secretes hormones
Insulin
Where is it from?
What does it do?
Insulin (from Beta Cell) —— Lowers blood glucose.
—Anabolic hormone because it uptakes amino acids and fats
Glucagon
From a cell
—It maintains glucose levels or increases it if needed
Somatostatin
from (delta cell)
Inhibits hormones; Controls the rate of nutrient intake
What hormones come from gonads?
Testosterone and Estrogen and Progesterone
Testosterone
Released from testes
Androgenic (aka masculinizing)
Anabolic steroid ——(builds muscle)
Estrogen and Progesterone
Released from ovaries
Establish and maintain reproductive functions.
Progesterone—Catabolic
Estrogen—Anabolic
Control of testosterone secretion IMAGE
What stimulates the secretion of testosterone? ——LH
Control of estrogen secretion
What happens if you take testosterone steroids?
Builds muscles;
But the body could lose its ability to make testosterone itself.
Muscle as an endocrine gland:
Skeletal Muscle produces ____ during contractions
What does it do?
What else does it stimulate that causes inflammation?
myokines
1) Stimulates glucose uptake and fatty acid oxidation
2)
Interleukin 6 (IL-6)
Both proinflammatory and anti-inflammatory effect
….
Glycogenolysis is related to exercise intensity:
Highly intensive exercise results in greater and more rapid ___ depletion levels.
glycogen
___ (hormone) is a powerful simulator of glycogenolysis:
Highly intensive exercise results in a greater increase in ___.
epinephrine
plasma epinephrine
Why is the breakdown of muscle glycogen under a dual (redundant) control?
Because glucose levels are so important to the body. In life or death. So your body has multiple systems to make sure it happens
redundant control of glycogenolysis:
What are the 2 systems for glucose breakdown?
What stimulates glycogen breakdown?
Epinephrine
—stimulates glycogen breakdown
Ca++ Calmodulin
—stimulates glycogen breakdown
—Enhanced during exercise due to Ca++ release from sarcoplasmic reticulum
Know the graph of redundant control of glycogenolysis
- Epinephrine—Cycle AMP
- Ca++ — Calmodulin
What happens if you don’t replace glucose as you exercise?
You will become Hypoglycemic because blood glucose levels drop. You become weak and stop exercising.
- Yes, you have fat, but you don’t have blood glucose as fuel for your brain.*
Blood glucose homeostasis during exercise:
What are the 4 processes that plasma glucose if maintained?
where do you get the glucose from so glucose lvls aren’t depleted?
- Mobilization of Glucose from the liver store
- Mobilization of FFA from adipose tissue
– (has some blood glucose) - Glucogenesis
–from amino acids, lactate, and glycerol. - Blocking the entry of glucose into cells
— forces use of FFA as fuels
What are glucose homeostasis systems controlled by?
Controlled by permissive or slow-acting hormones
What is Glucogenesis?
Formation of new blood sugar!
Turns amino acids, lactate, and glycerol into glucose
It maintains plasma glucose.
(Active?) hormones from blood glucose homeostasis: Thyroid hormones
How do hormone levels change during exercise?
THYROXINE
T3 and T4 don’t really change during exercise because there’s an increased clearance, followed by an increase in TSH.
They are permissive hormones.
Slow-acting hormones from blood glucose homeostasis: Cortisol
What does it do?
What does cortisol respond to? When you exercise, do you increase or decrease cortisol levels?
What does it do? Catabolic
1. FFA Mobilization for fuel
2. Enahnces gluconeogenesis at the expense of protein
(Breaks down protein)
3. Decreases rate of glucose utilization by cells
a. Stop glucose from being used
b. It will block the entry of glucose
Cortisol increases under stress. Which means it increases during exercise.
(Highest levels in the morning.)
What’s the difference between slow-acting hormones?
Passive hormones
—Permissive
—allows other hormones to be more active (and work more effectively)
—Thyroxine, cortisol, and growth hormone
Active hormones
—Epinephrine, norepinephrine, insulin, and glucagon
Growth Hormone
A fast or slow-acting hormone?
Effects on CHO Metabolism?
Exercise effect?
Slow Acting Hormone
—anabolic (build)
Effects: Supports actions of cortisol:
—Decreases glucose uptake by tissues
— Increases free fatty acid mobilization
— Enhances gluconeogenesis in the liver
Exercise effect:
Increases plasma GH with increased intensity (greater in trained runners)
Epinephrine and Norepinephrine
Passive or active?
Where does it come from?
What do they do?
Fight or Flight
Fast-acting hormones
Catecholamines from the adrenal medulla
Effect: Maintain blood glucose during exercise
1. Increase muscle and liver glucose mobilization from glycogen
2. Increase FFA mobilization
3. Interfere with glucose uptake
If your heart rate spikes, so does your blood pressure. Why?
Because of Epinephrine and Norepinephrine
If you exercise submaximally, then your Plasma Epinephrine and Norepinephrine levels with ___ during exercise
decreases
At supramaximal exercise in trained individuals, you will increase ___ Epinephrine and Norepinephrine levels during exercise
increased
What are counter-regulatory hormones? Hormones that oppose each other?
Where are they from?
Fast or slow?
Insulin and glucagon from panceratic
FAST
What is Glucagon? What is the effect on the blood on trained vs. untrained people?
Fast or slow?
Effect
—Mobilizes glucose and FFA.
—Plasma concentration increases during exercise
— Decreased response following training
Slide 50
What is Insulin? What is the effect on the blood on trained vs. untrained people?
Fast or slow?
Effect
—Uptake and storage of glucose and FFA
—Plasma concentration decreases during exercise
—Decreased insulin response following training
Do you need insulin when you exercise?
NO
What is the glucose and insulin ratio after a meal?
Absorption of a meal:
1. Inlsin is secreted (which decreases blood glucose)
2. Insulin goes up, glucagon goes down
3. Wants to store glycogen, fat, and protein.
What is the glucose and insulin ratio During Fasting for exercise?
During Fasting for exercise
1. Glucagon levels increase
2. Break down glucose for energy (Hydrolysis)
What is the Effect of epinephrine/norepinephrine on insulin and glucagon secretion
What is the Effect of the sympathetic nervous system on substrate mobilization?
They all work to elevate your blood levels to a normal level.
During exercise, which hormones increase or decrease?
Increase:
—Epinephrine and Norepinephrine
—Growth hormone
—Cortisol
—Glucagon
Decrease:
—Insulin
Why is FFA mobilization prevented during heavy exercise?
- Relying on fast glycolysis means you have high levels of lactate, which promotes
the resynthesis of triglycerides.
(It is promoting fat synthesis instead of fat breakdown) - Elevated H+, which inhibits HSL
(You become more acidic, so it decreases the activity of proteins) - Reduced blood supply, which reduces FFA Transport.
(HIgh exercise forces blood out of the muscle/area.) - Inadequate albumin levels reduce FFA transport
(Ablumin helps transport fat. and when that is reduced, you can’t use it as a fuel source)
