thyroid and pancreas

Question 1

What hormone does the thyroid gland release to regulate calcium levels?

Answer 1

Calcitonin

Question 2

What does calcitonin do when calcium levels are high?

Answer 2

Increases calcium storage and reduces uptake

Question 3

What are the two major thyroid hormones involved in metabolism?

Answer 3

Thyroxine (T4) and Triiodothyronine (T3)

Question 4

Which thyroid hormone is the pro-hormone?

Answer 4

Thyroxine (T4)

Question 5

Which thyroid hormone is the active form?

Answer 5

Triiodothyronine (T3)

Question 6

What hormone do the parathyroid glands release?

Answer 6

Parathyroid hormone (PTH)

Question 7

When is parathyroid hormone released?

Answer 7

When calcium levels are low

Question 8

What does parathyroid hormone do?

Answer 8

Increases calcium release and uptake

Question 9

What are the main functions of thyroid hormones?

Answer 9

Energy balance, temperature regulation, increased protein synthesis, and carbohydrate burning

Question 10

What is the precursor for T3 and T4 synthesis?

Answer 10

Thyroglobulin + iodine

Question 11

How are T3 and T4 formed from the precursor?

Answer 11

The precursor is separated into T3 and T4

Question 12

Which thyroid hormone is more abundant in circulation?

Answer 12

T4 (prohormone)

Question 13

Which thyroid hormone has higher receptor affinity?

Answer 13

T3

Question 14

Where does most thyroid hormone activity come from?

Answer 14

T3 converted from T4 in the periphery

Question 15

What carrier protein protects thyroid hormones in circulation?

Answer 15

Thyroxine-binding globulin (TBG)

Question 16

Where does T3 bind inside the cell?

Answer 16

It binds to its receptor in the nucleus

Question 17

What do hormone-bound receptors do?

Answer 17

Bind to DNA response elements and regulate transcription

Question 18

What hormone does the hypothalamus release to regulate thyroid function?

Answer 18

TRH (Thyrotropin-releasing hormone)

Question 19

What does TRH stimulate?

Answer 19

The anterior pituitary to release TSH

Question 20

What does the Thyroid-stimulating hormone stimulate?

Answer 20

The thyroid gland to produce T3 and T4

Question 21

What are the effects of T3 and T4 on the body?

Answer 21

Increase metabolism and maintain energy balance

Question 22

What kind of feedback loop is involved in thyroid hormone regulation?

Answer 22

Negative feedback

Question 23

What do T3 and T4 inhibit in the feedback loop?

Answer 23

TRH from the hypothalamus and TSH from the anterior pituitary

Question 24

What is the metabolic effect of hypothyroidism?

Answer 24

Decreased metabolism

Question 25

What are general symptoms of hypothyroidism?

Answer 25

Fatigue, cold intolerance, weight gain, thin hair, dry skin

Question 26

What are dental considerations for hypothyroid patients?

Answer 26

Increased sensitivity to central nervous system depressants, difficulty withstanding stress

Question 27

What is the treatment for hypothyroidism?

Answer 27

T4 (thyroxine)

Question 28

What is the metabolic effect of hyperthyroidism?

Answer 28

Increased metabolism

Question 29

What are general symptoms of hyperthyroidism?

Answer 29

Osteoporosis, insomnia, anxiety, heat intolerance, rapid heartbeat, weight loss

Question 30

What are oral effects of hyperthyroidism?

Answer 30

Increased risk of caries, periodontal disease, osteoporosis, accelerated dental eruption, burning mouth syndrome

Question 31

What are treatments for hyperthyroidism?

Answer 31

Inhibit thyroid hormone synthesis (thioamides), remove the gland

Question 32

What is thyrotoxicosis?

Answer 32

Excess circulating thyroid hormones

Question 33

What is the CNS response in thyrotoxicosis?

Answer 33

Increased tolerance to central nervous system depressants

Question 34

What are oral effects of thyrotoxicosis?

Answer 34

Accelerated tooth eruption, jawbone demineralization, periodontal destruction

Question 35

What is a thyroid storm?

Answer 35

A complication of persistent thyrotoxicosis, triggered by stress

Question 36

What stimulates insulin secretion?

Answer 36

High blood glucose

Question 37

What does insulin do to blood glucose?

Answer 37

Lowers it by promoting glucose uptake by cells

Question 38

How does insulin store glucose?

Answer 38

Promotes storage as glycogen

Question 39

What stimulates glucagon secretion?

Answer 39

Low blood glucose

Question 40

What does glucagon do?

Answer 40

Stimulates gluconeogenesis (breakdown of glycogen)

Question 41

What inhibits glucagon secretion?

Answer 41

High blood glucose

Question 42

What transporter allows glucose to enter pancreatic beta cells?

Answer 42

GLUT2

Question 43

What happens when potassium channels close in beta cells?

Answer 43

The cell depolarizes

Question 43

What does glucose metabolism in beta cells produce?

Answer 43

ATP

Question 44

What does ATP do in beta cells?

Answer 44

Closes ATP-sensitive potassium channels

Question 45

What does calcium influx trigger in beta cells?

Answer 45

Insulin release

Question 45

What opens as a result of depolarization?

Answer 45

Voltage-gated calcium channels

Question 46

What does insulin bind to on target cells?

Answer 46

Insulin receptors

Question 47

What does receptor binding activate?

Answer 47

Signal transduction cascade

Question 48

What does signaling cause GLUT4 to do?

Answer 48

Insert into the cell membrane

Question 49

What happens after GLUT4 inserts into the membrane?

Answer 49

Glucose enters the cell

Question 50

What is the cause of Type 1 diabetes?

Answer 50

Pancreas does not produce insulin (insulin-dependent)

Question 51

What is the cause of Type 2 diabetes?

Answer 51

Peripheral tissues do not respond to insulin (insulin-resistant)

Question 52

What is diabetic neuropathy in the oral context?

Answer 52

Reduced or absent sensation; pain and burning sensations

Question 53

What is insulin therapy used for?

Answer 53

Required for type 1 diabetes; may be needed for type 2

Question 53

What can severe hypoglycemia (<40 mg/dL) lead to?

Answer 53

Convulsions and coma

Question 54

What is a major adverse effect of insulin therapy?

Answer 54

Hypoglycemia

Question 55

What do sulfonylureas and meglitinides do?

Answer 55

Increase insulin release from the pancreas

Question 56

What is a side effect of sulfonylureas and meglitinides?

Answer 56

Hypoglycemia

Question 57

What is their mechanism of action?

Answer 57

Inhibit ATP-sensitive potassium (KATP) channels to stimulate beta cells

Question 58

What do GLP-1 and GIP agonists (incretins) do in the pancreas?

Answer 58

Enhance insulin release and reduce glucagon

Question 59

What do GLP-1 and GIP agonists (incretins) do in the gut?

Answer 59

Slow glucose absorption

Question 60

What is the function of DPP-4 inhibitors?

Answer 60

Enhance incretins by inhibiting the enzyme that degrades them

Question 60

What do GLP-1 and GIP agonists (incretins) do in the brain?

Answer 60

Reduce appetite

Question 61

What are the effects of DPP-4 inhibitors?

Answer 61

Same as GLP-1 and GIP agonists (enhance insulin, reduce glucagon, slow absorption, reduce appetite)

Question 62

What is the action of thiazolidinediones?

Answer 62

PPARγ agonist; enhances tissue sensitivity to insulin

Question 63

What is the main action of biguanides in the liver?

Answer 63

Reduce gluconeogenesis

Question 64

What is the main action of biguanides in muscle tissue?

Answer 64

Enhance glucose utilization

Question 65

What is the action of amylin analogs in the pancreas?

Answer 65

Reduce glucagon secretion

Question 66

What is the action of amylin analogs in the brain?

Answer 66

Slow gastric emptying and decrease food intake

Question 67

What is the mechanism of alpha-glucosidase inhibitors?

Answer 67

Delay carbohydrate digestion in the gastrointestinal tract

Question 68

What is the effect of alpha-glucosidase inhibitors on blood glucose?

Answer 68

Smaller post-meal rise in glucose

Question 69

What do SGLT2 inhibitors do?

Answer 69

Inhibit sodium-glucose co-transporter 2 in the kidney

Question 70

What is the result of SGLT2 inhibition?

Answer 70

Reduces glucose reabsorption → increases glucose excretion