insulin and hypoglycaemia Flashcards
(34 cards)
values for hypoglycaemia?
less than 3mmol/L of glucose
normal, healthy fasting glucose levels?
3-5mmol/L glucose
values for hyperglycaemia?
more than 10mmol/L of glucose
describe glucosuria:
when elevated glucose levels saturate the glucose reuptake mechanism in the kidney; leading to osmotic diuresis, increases thirst and urine production, dehyrdration, unconsciousness and death
action of insulin?
acts on target cells such as the liver, muscle, adipocytes and CNS to lower blood glucose levels
where is insulin produced?
pancreatic B cells
action of glucagon?
glucagon increases blood glucose levels, endogenous glucose production occurs in the liver
where is glucagon produced?
in the pancreatic a-cells of the islets of langerhan
different cell types within islets of langerhan and what they produce?
a cells; release glucagon, b cells; release insulin, PP cells; release pancreatic polypeptide, cells that release grehlin, and cells that release somatostatin.
what are incretin hormones?
hormones that increase insulin. e.g. glucagon-like peptide 1 (GLP1) and gastric inhibitory peptide (GIP)
where are incretin hormones found, and what is their function?
found in the endocrine cells of the GI tract; they circulate the blood and signal secreting cells to release insulin
other insulin functions?
promote hypoglycaemia, increases; glucose uptake, storage and utilization, protein synthesis, triglyceride synthesis, gene expression, growth hormones. it decreases; proteolysis, lipolysis and lipid oxidation
describe the process of insulin lowering blood glucose levels?
high blood sugar –> b-cells release insulin into the blood –> insulin binds to receptors on target cells –> biochemical / signal transduction cascade of events –> glut4 transporter activated –> glucose transported out of the blood stream, into the muscle –> blood sugar levels decrease
affects of glucose on the liver?
turns stored glycogen into glucose, increases endogenous glucose production and allows fat cells to be broken down.
what is diabetes mellitus?
type one; when the pancreas does not produce enough insulin. type two; when the body cannot effectively use insulin. this leads to hyperglycaemia.
strategies for the treatment of T1DM;
insulin therapy, islet/pancreas transplantation, prevention
four preparations for insulin therapy?
short duration - e.g. insulin aspart, intermediate action e.g. iosphone insulin, long lasting e.g. protamine zinc insulin and biphasic insulin preparation
how is insulin administered?
subcutaneous injection, 3-4 times per day.
aim of glucagon therapy?
hyperglycaemia inducing. first aid treatment for severe hypoglycaemia. it acutely raises plasma glucose levels
side effects of glucagon therapy?
headache and nausea
function of insulin secretagogues I?
boost insulin release, enhance normal physiology of glucose-stimulated insulin secretion
examples of insulin secretagogues I?
sulphonylureas, meglitinides
function of insulin secretagogues II and examples?
exenatide, liraglutide; boost insulin release by enhancing normal physiology of incretin-mediated insulin secretion
function of secretagogues III and examples?
boost insulin release by enhancing normal physiology of incretin-mediated insulin. e.g. gliptins
