Physiology Ii Lc Pancreas

Front 1

how long is the pancreas?

Back 1

5 inches

Front 2

what % of cells produce digestive enzymes

Back 2

99%

Front 3

what cells produce hormones

Back 3

islet cells

Front 4

are the islets endocrine or exocrine

Back 4

endocrine

Front 5

what do exocrine cells surround?

Back 5

a ducts

Front 6

what are endocrine cells near?

Back 6

capillaries

Front 7

what do alpha cells secrete?

Back 7

glucagon

Front 8

what do beta cells secrete?

Back 8

insulin

Front 9

what do delta cells secrete?

Back 9

somatostatin

Front 10

what do F-cells secrete?

Back 10

pancreatic polypeptide

Front 11

how would you test for hormone levels

Back 11

radioimmuno assays

Front 12

how many islet cells are there in the pancreas?

Back 12

1 to 2 million

Front 13

what % of the islet cells are alpha cells, and what do they produce

Back 13

20% and glucagon

Front 14

what % of the islet cells are beta cells, and what do they produce?

Back 14

70% and insulin

Front 15

what % of the islet cells are delta cells and what do they produce?

Back 15

5% and somatostatin

Front 16

what is the effect of insulin on muscle?

Back 16

promotes glucose uptake and metabolism, insulin increases permeability to glucose

Front 17

is skeletal muscle more or less permeable to muscle during exercise?

Back 17

more permeable

Front 18

if there is excess glucose in a muscle fiber, what does insulin do?

Back 18

it promotes storage of glucose as glycogen

Front 19

what is the effect of insulin on the liver?

Back 19

it promotes glucose uptake, storage and use

Front 20

what does insulin do to phosphorylase in the liver?

Back 20

it inactivates it

Front 21

what effect does insulin have on glycogen synthase in the liver?

Back 21

increases its activity (need to make glycogen)

Front 22

what is the effect on glucokinase in the liver?

Back 22

increases its activity - need to phosphorylate glucose to trap it in the cell and maintain the concentration gradient

Front 23

if the liver glyogen stores are full and there is extra glucose left over what will the liver do?

Back 23

it will begin converting glucose into fatty acids and triglycerides

Front 24

as the insulin levels decrease between meals, what happens to phosphorylase?

Back 24

it increases activity and begins splitting glycogen back into glucose

Front 25

as insulin levels fall between meals what happens to glucose phosphatase?

Back 25

it is activated, it will dephosphorylate glucose so that it can leave the liver and go to other parts of the body

Front 26

what is the effect of insulin on the brain?

Back 26

none, the brain cells are always permeable to glucose irrespective of insulin

Front 27

how does insulin effect lipid metabolism?

Back 27

it promotes fat synthesis and storage

Front 28

what will glucose be converted to on its way to becoming a fatty acid?

Back 28

glucose -->pyruvate-->acetyl CoA--> fatty acid

Front 29

what carries Fatty acids from the liver to adipocytes?

Back 29

VLDL

Front 30

what is the effect of insulin on adipose capillaries?

Back 30

it activates lipoprotein lipase

Front 31

what is the function of lipoprotein lipase?

Back 31

it breaks down the triglycerides for absorption by the adipocyte

Front 32

inside of an adipocyte, what is the effect of insulin?

Back 32

it inhibits lipases to prevent fat catabolism, and induces the formation of glycerol phosphate

Front 33

what will happen if there is a lack of insulin?

Back 33

lipolysis of stored FA and release of FFA by activating hormone sensitive lipase, increased cholesterol and phospholipid production (can lead to arteriosclerosis) and excess acetoacetic acid production for synthesis of ketone bodies

Front 34

what is the effect of insulin on protein metabolism?

Back 34

stimulates AA uptake by tissues, increases protein translation from mRNA, regulates gene expression, inhibits protein catabolism, decreases gluconeogenesis, interacts synergistically with growth hormone

Front 35

what effect does a lack on insulin have on protein metabolism?

Back 35

it leads to protein degradation and increase in AA's in blood plasma

Front 36

what are the factors that stimulate insulin secretion?

Back 36

increased glucose, amino acid, fatty acid, and keto acid concentrations, glucagon, growth hormone, cortisol, GIP, potassium, vagal stimulation (acetylcholine), sulfonylurea drugs, and obesity

Front 37

what factors inhibit insulin secretion?

Back 37

decreased blood glucose, fasting, exercise, somatostatin, alpha-adrenergic agonists, diazoxide

Front 38

what effect will sympathetic stimulation have on insulin secretion?

Back 38

it will inhibit insulin's secretion

Front 39

increased epinephrine from the adrenal medulla will lead to?

Back 39

inhibition of insulin secretion

Front 40

what are the three major effects of glucagon?

Back 40

1. breakdown of liver glycogen 2. increased gluconeogenesis in the liver 3. stimulates lipolysis

Front 41

what effect does glucagon have on adenyl cyclase?

Back 41

increased it activity which leads to an increase in cAMP, which leads to the release glycogen from the liver

Front 42

what does phosphorylase A do to glycogen?

Back 42

it splits it into glu-1-P, which is dephosphorylated and released from the liver as glucose

Front 43

will secretion of glucagon lead to protein anabolism or catabolism

Back 43

catabolism, via gluconeogenesis, to maintain constant blood glucose levels

Front 44

what effect does glucagon have on lipases?

Back 44

it increases their activtiy to mobilize FA's for energy and preserve glucose

Front 45

what inhibits glucagon secretion?

Back 45

insulin, somatostatin, free fatty acids, and ketones

Front 46

what stimulates glucagon secretion?

Back 46

fasting, decreased glucose concentration, increased AA concentration (especially arginine), CCK, beta-adrenergic agonists, acetylcholine

Front 47

what factors inhibit glucagon secretion?

Back 47

insulin, somatostatin, increased FA and ketoacid concentration

Front 48

hyperglycemia will stimulate or inhibit glucagon?

Back 48

inhibit

Front 49

hypoglycemia will stimulate or inhibit insulin?

Back 49

inhibit

Front 50

hyperglycemia will stimulate or inhibit insulin?

Back 50

stimulate

Front 51

hypoglycemia will stimulate or inhibit glucagon?

Back 51

stimulate

Front 52

what are the target tissues for insulin?

Back 52

liver, adipose tissue, muscle, satiety center in the hypothalamus

Front 53

what is the target tissue for glucagon?

Back 53

the liver

Front 54

if you are looking to build muscle mass, which hormone is more important to stimulate, insulin or glucagon?

Back 54

insulin

Front 55

what is the function of somatostatin?

Back 55

to decrease motility of the stomach, duodenum, gall bladder. It also decreases secretion and absorption in the GI

Front 56

what effect does somatostatin have on glucose and insulin?

Back 56

it inhibits them

Front 57

insulin stimulates or inhibits somatostatin?

Back 57

inhibits

Front 58

glucagon stimulates or inhibits somatostatin?

Back 58

stimulates

Front 59

what causes diabtes mellitus?

Back 59

inadequate secretion of insulin or inability of tissue to respond to insulin

Front 60

what is the difference between type I and type II diabetes mellitus

Back 60

Type I is insulin dependent, Type II in non-insulin dependent

Front 61

if there is a decrease in insulin associated with diabetes mellitus where is the problem?

Back 61

the beta cells are defective (potentially due to autoimmune disorders or viral infections)

Front 62

if there is decreased insulin secretion then what problem will arise?

Back 62

there will be very high levels of glucose in the blood

Front 63

what are some clinical signs that one may have diabetes mellitus?

Back 63

glucose in urine, dehydration (due to osmotic diuresis), polyurea (intra & extracellular dehydration), unquenchable thirst, ketoacidosis, protein breakdown

Front 64

what are some secondary effects of diabetes mellitus?

Back 64

hypertension and atherosclerosis

Front 65

what is the treatment for Type I diabetes?

Back 65

insulin therapy

Front 66

what is the major issue with Type II daibetes

Back 66

decreased sensitivity to insulin

Front 67

what is the primary cause of Type II diabetes

Back 67

obesity

Front 68

does a patient with Type II have to be on insulin therapy?

Back 68

no, many can be managed by diet, caloric restrictions

Front 69

are there treaments other than insulin for type II diabetes?

Back 69

yes, thiazolidinediones and metformin to increase insulin sensitivity and sufonylurease to increase insulin secretion

Front 70

what is the function of pancreatic polypeptide?

Back 70

it inhibits somatostatin secretion, gall bladder contraction and secretion of pancreatic digestive enzymes

Front 71

what is the function of the thymus gland?

Back 71

its secretions promote proliferation and maturation of T cells

Front 72

what hormones are secreted by the thymus?

Back 72

thymosin, thymic humoral factor, thymic factor, thymopoietin

Front 73

what are eicosanoids?

Back 73

they are local hormones secreted by all body cells

Front 74

what are the two families of eicosanoids?

Back 74

leukotrienes and prostaglandins

Front 75

what do leukotrienes influence?

Back 75

WBC's and inflammation

Front 76

what do prostaglandins do?

Back 76

they alter smooth muscle contraction, glandular secretion, blood flow, platelet function, nerve transmission, metabolism, etc.

Front 77

what is the major function of prostaglandins?

Back 77

control of vascular smooth muscle activity

Front 78

what are the localized actions of PGE/F?

Back 78

act on microcirculation & adjust local blood flow in response to changing metabolic requirements of the tissue

Front 79

what is PGI

Back 79

prostacyclins

Front 80

what do prostacyclins do?

Back 80

it is a potent inhibitor of platelet aggregation - maintains vascular flow

Front 81

where are prostacyclins produced?

Back 81

by the endothelium on the blood vessel walls

Front 82

what is the role of thromboxanes?

Back 82

may play a role in Ca+ ionophore to increase Ca, Ca may in turn regulate the changes in cellular shape needed for platelet aggregation

Front 83

where are leukotrienes made?

Back 83

in leukocytes

Front 84

what is the function of leukotrienes?

Back 84

the are potent vasoconstrictors, increase vascular permeability, induce inflammation or allergic response in sites of injury or invasion by foreign agents