chapter 16, pancreas and diabetes

glycogenesis

conversion of glucose and glycogen for storage in the liver

endocrine pancreas

1% of the organs volume, 1 gram, and consists of small groups of clusters "pancreatic islets", secrets hormones

in an adult the pancreas is how big and weighs what

20-25 CM and weighs about 80 grams

normal blood glucose levels

70-110 MG/DL

exocrine pancreas

99% of the organs volume, has clusters of gland cells and their attached ducts, together the glands and ducts secrete pancreatic fluid and enzymes with digestive function

type 1 diabetes

INSULIN DEPENDENT - WHAT IS IT: inadequate insulin production by pancreatic beta cells. treatment: daily multiple insulin injections, only 5-10% of diabetes cases are type 1, often develops in childhood

type 2 diabetes

NON-INSULIN DEPENDENT. what is is- there are normal insulin levels in the blood but target cells dont respond properly, the target cells are resistant. assiciated with obesity, treated with diet, excercise and drugs, 90% of diabetics in the US are type 2

what are the 2 primary hormones controlling blood glucose homeostasis

insulin and glucagon, these two hormones have opposing (antagonistic) effects

hyperglucemia

abnormally high blood glucose levels. associated with diabetes mellitus

as blood glucose declines....

alpha cells secrete glucagon causing liver cells to break down glycogen and release glucose into the blood therefore raising glucose levels in the blood

why does a person with untreated diabetes mellitus urinate frequently?

an individual with type 1 or type 2 diabetes has such high blood glucose levels that the kidjeys cannot reabsorb all of the glucose, some of the glucose is lost in the urine. becuase the urine contains high levels of of glucose less water can be reclaimed by osmosis so the urine volume increases

as blood glucose rises.....

beta cells secrete insulin into the blood, insulin inserts glucose transporters into cell membranes of skeletal muscles in adipose allowing glucose to enter, therefore lowering blood glucose

diabetes mellitus is a condition which

either the pancreas doesnt make enough insulin or insulin is not utilized properly (target cells don't respond properly to insulin) (insulin resistant)

gluconeogenesis

generation of glucose

ALPHA CELLS =

glucagon

what two hormones have opposing (antagonistic) effects

glucagon and insulin

glycosuria

glucose appearing in the urine, associated with diabeted mellitus

diabetes mellitus

glucose concentrations high enough to overwhelm kidney reabsorbtion, symptoms include - hyperglycemia, glucosuria, polysuria

alpha cells

in the ENDOCRINE pancreas, alpha cells produce glucagon, which raisesblood glucose by increasing liver glycogen breakdown and increasing glucose release by the liver

Beta cells

in the ENDOCRINE pancreas, beta cells produce the hormone insulin which lowers blood glucose levels by increasing the rate of glucose uptake and utilization by cells and also increasing lgucogen production in the liver and skeletal muscles

release of glucagon from alpha cells does what

increased breakdown of glycogen to glucose in liver and skeletal muscles, increased breakdown of fat to fatty acids in adipose tissue, increased synthesis and release of glucose in the liver

what is the effect of increased glucagon levels on the amount of glycogen stored in the liver?

increased leveles of glucagon stimulate the conversion of glycogen to glucose in the liver, which would in turn reduce the amount of glycogen stored in the liver

secretion of insulin from beta cells causes

increased rate of glucose transport into target cells, increased rate of glucose utilization and ATP generation, increased conversion of glucose to glycogen

cardiovascular complications involved with diabetes

increases high blood pressure, leveles of cholestrol and triglycerides, increasing the risk of heart disease, kidney disease and other blood vessel complications, diabetes accelorates atherosclerosis which can lead to blockages or a clot in an artery which can lead to heart attack, stroke and decreased circulationm int he arms and legs

BETA CELLS =

insulin

secretion of what hormone lowers blood glucose concentrations

insulin

complications involved with diabetes

long-term hyperglycemia damages the retina of the eye, blood vesseles of the kidneys the nerves and other blood vessels, blidness due to damage of the retina, kidney failure, neuropathy leads to numbness, then foot wounds ulcers on feet,leads to AMPUTATIONS OF THE LEG AND FEET

symptoms of diabetes

polydypsia, polyuria, unexplained weight loss, polyphagia, lethargy, blood glucose >300Mg/dl, ketoacidosis, fruity odor of break, serum PH <7.3, hyperpnea

what does glycogen do?

raises blood glucose levels by increasing the rates of glycogen breakdown and glucose release by the liver

what are the two types of diabetes mellitus?

type 1- insulin depedent and type 2-non-insulin dependent

polyuria

urine volume becomes excessive. assiciated with diabetes mellitus

where does the pancreas lie?

within the abdominopelvic cavity below the stomach