Term
| What are the 3 hormones produced in the thyroid follicles? |
|
Definition
|
|
Term
| What is the thyroid hormone produced in the parafollicular cells? |
|
Definition
|
|
Term
| What is another name for the parafollicular cells? |
|
Definition
|
|
Term
| Are thyroid hormones synthesized extracellularly within the follicular lumen? |
|
Definition
|
|
Term
| What stimulates the "Iodide Trap" and what transports it into the lumen? |
|
Definition
| It is stimulated by TSH and is transported by Pendrin |
|
|
Term
| What process makes Iodide become Iodine? |
|
Definition
|
|
Term
| Iodine combines with tyrosine to create MIT and DIT. How do they combine to become T4 and T3, rT3? |
|
Definition
DIT + DIT = T4
DIT + MIT = T3, rT3 |
|
|
Term
| What happens when the thyroid gland follicle is stimulated by TSH? |
|
Definition
1. forms cytoplasmic pseudopodia
2. increased endocytosis of colloid
3. release of pre-formed hormone |
|
|
Term
| What are the 3 main hormones that regulate synthesis and release of thyroid hormones? |
|
Definition
1. TRH(hypothalamus)-->TSH (adenohypophysis)
2. Somatostatin (inhibited)
3. TSH |
|
|
Term
| What specific role does TSH play in control of thyroid hormones? |
|
Definition
| it binds to the follicular cell membrane receptor and activates the second messenger system. |
|
|
Term
| What is the thyroid hormone second messanger? |
|
Definition
| adenylyl cyclase --> cAMP |
|
|
Term
| What syndrome is caused by excessive iodide intake? |
|
Definition
|
|
Term
| Where is leptin found and what is its action? |
|
Definition
1.Found in the CNS
2. regulates by changing levels of energy intake and adipose tissue stores |
|
|
Term
| What is the nucleus in the brain that secretes Leptin? |
|
Definition
|
|
Term
| What is the result of thyroid hormone deficincy? |
|
Definition
High Leptin
Decreased Appetite
Increased Adipose Stores |
|
|
Term
| What is the result of excess thyroid hormone? |
|
Definition
decreased adipose stores
decreased leptin
increases food intake |
|
|
Term
| What is the result of excess thyroid hormone? |
|
Definition
decreased adipose stores
decreased leptin
increases food intake |
|
|
Term
| What is Sick Euthyroid Syndrome? |
|
Definition
| The interuption of T4 and T3 function due to fasting, catabolic disease, renal failure, hepatic failure, and stress (cortisol). |
|
|
Term
| What is the most predominat hormone made by the thyroid gland? |
|
Definition
|
|
Term
| What is the biologically active thyroid hormone at the target cell level? |
|
Definition
|
|
Term
| What enzyme converts T4 to T3? |
|
Definition
|
|
Term
| What enzyme converts T4 to rT3? |
|
Definition
|
|
Term
| What are the equations for total T4 and T3? |
|
Definition
| Total = Free(active) + Bound(inactive) |
|
|
Term
| What are the equations for total T4 and T3? |
|
Definition
| Total = Free(active) + Bound(inactive) |
|
|
Term
| What are the 3 protiens that prevent the excretion of T4? |
|
Definition
1. TBG
2. Transthyretin
3. Albumin |
|
|
Term
| What variations change hormone plasma concentrations? |
|
Definition
1. age
2. episodie secretion
3. breed/ species |
|
|
Term
| How are thyroid hormones degraded? |
|
Definition
1. de-iodianted and I recycled
2. liver, kidney, and skeletal muscle
3. excretion in bile |
|
|
Term
| What are the 5 main body systems do thyroid hormones act on? |
|
Definition
1. Respiratpory/Thermoregulatory
2. Nutrient Metabolisim
3. Nervous System
4. Growth and Development
5. Reproduction |
|
|
Term
| What affects to TH have on the respiratory and cardiac system? |
|
Definition
1. Inceased O2 Supply
2. Increased RR
3. Increased RBC
4. Increased Cardiac Output
5. Increased Stroke Volume
6. Increased Pulse |
|
|
Term
| What are the main nutrients affected by TH and how? |
|
Definition
1. Carbohydrate: increases gluconeogenisis and glycolysis
2. Lipid
lipolysis with adipose sensetization
enhance chylomicron clearance
stimulates cholesterol synthesis
3. Protein
increased protein turnover and proteinolysis |
|
|
Term
| How do catecholamines and TH interact? |
|
Definition
| Thyroid hormones act on increasing the sensivity to catecholamines (secreted by the CNS). |
|
|
Term
| Are TH absolutely neccessary for growth and development? |
|
Definition
YES!
mediated by: Growth Hormone/Somatomedins |
|
|
Term
| What are the 3 ways hormones play a role in reproduction... what are they? |
|
Definition
1. ovarian
2. spermatogenesis
3. maintenence of normal pregnancy |
|
|
