Physiology

Question 0

Insulin independent tissues

Answer 0

BRICK L

Brain
RBCs
Intestine
Cornea
Kidney
Liver

Question 1

Anabolic effects on insulin

Answer 1

Increased glucose transport in skeletal m. And adipose
Increased glycogen synthesis and storage
Increased TG synthesis and storage
Increased Na retention in kidneys
Increased protein synthesis in muscles
Increase cellular uptake of K+ and amino acids
Decreased glucagon release

Question 2

GLUT-1 receptors

Answer 2

Insulin independent

RBCs, brain

Question 3

GLUT-2 receptors

Answer 3

Bidirectional

Beta islet cells, liver, kidney, small intestine

Question 4

GLUT-4 receptors

Answer 4

Insulin dependent

Adipose tissue, skeletal m.

The more insulin present, the more receptors inserted on surface

Question 5

Increases insulin release

Answer 5

Hyperglycemia, GH, B2 antagonists

Question 6

Decreased insulin release

Answer 6

Hypoglycemia, somatostatin, a2 agonists

Question 7

Insulin and c peptide exit cell via…..

Answer 7

Exocytosis in granules

Question 8

Glucose major regulator of insulin via what mechanism…..

Answer 8

ATP generated from glycolysis leads to K channels closing and depolarizing beta cell membrane, opens voltage gated Ca2+ channels and intracellular calcium increases, insulin secreted

Question 9

Insulin signaling pathway for glucose uptake…..describe the 2 paths….

Answer 9

1. Tyrosine phosphorylation, IP3 , stimulates glycogen/lipid/protein synthesis and vesicles containing GLUT-4
2. Tyrosine phosphorylation, RAS/MAP kinase, cell growth, DNA synthesis

Question 10

Glucagon catabolic effects

Answer 10

Glycogenolysis
Gluconeogenesis
Lipolysis
Ketone production

Question 11

TRH stimulates

Answer 11

TSH, prolactin

Question 12

Dopamine inhibits

Answer 12

Prolactin

Question 13

CRH stimulates

Answer 13

ACTH, melanocyte stimulating hormone, beta-endorphin

Question 14

GHRH stimulates

Answer 14

GH

Question 15

Somatostatin inhibits

Answer 15

GH, TSH

Question 16

GnRH stimulates

Answer 16

FSH, LH

Question 17

Prolactin inhibits

Answer 17

GnRH

Question 18

PTH released from

Answer 18

Chief cells of parathyroid

Question 19

Low calcium levels when thyroid removed….

Answer 19

Parathyroid glands sometimes are removed with thyroidectomy and is a common cause for hypocalcemia

Question 20

Increased production of what hormones in osteoblasts in response to PTH

Answer 20

M-CSF and RANK-L

These then stimulate osteoclasts to become active

Question 21

Stimulates vitamin D production

Answer 21

High PTH, low calcium, low phosphate–> causes increased 1,25-OH2 production which is activated vitamin D

Question 22

Stimulates PTH production

Answer 22

Low serum calcium and low magnesium

Question 23

Inhibits PTH production

Answer 23

VERY LOW magnesium which can be caused by diarrhea, diuretics, aminoglycosides, and alcohol abuse

Question 24

Calcitonin secreted from what cells

Answer 24

Parafollicular cells (C cells) of thyroid which are derived from neural crest cells

Question 25

T3 functions

Answer 25

4 Bs

Brain maturation
Bone growth
Beta adrenergic effects
Basal metabolic rate

Question 26

Peroxidase enzyme has 3 functions…..

Answer 26

Oxidation and organification of iodide

Coupling MIT and DIT

Question 27

Propylthiouracil inhibits…..

Answer 27

Peroxidases and 5’- diodinase

Question 28

Methimazole inhibits…..

Answer 28

Peroxidase only

Question 29

Thyroxine binding globulin (TBG) binds…..

Answer 29

T3 and T4 in blood

Only free hormone is active so when bound to TBG it is NOT active

Low TBG in hepatic failure
High TBG in pregnancy and OCPs (estrogen increases TBG)

Question 30

Wolf-Chaikoff effect

Answer 30

Excess iodine temporarily inhibits thyroid peroxidase which decreases organification and T3/T4 production