Endocrine Flashcards
What does D/L mean?
It is the rotation of a plane of polarised light. D is naturally occurring and rotates the plane to the right.
What is the commitment step in glycolysis?
PHOSPHOFRUCTOKINASE, it is inhibited by citrate, ADP, ATP.
Fructose is converted into molecules that can be used as intermediates of glycolysis, what are they?
DHAP and G3P
What is a Hexokinase?
An enzyme that phosphorylates e.g. hexose (glucose) producing hexose phosphate (G6P)
No matter what the fate of glucose is what is a common step between them all?
Glucose must be phosphorylated to Glucose-6-phospahte
What is the proportion of beta and alpha cells in the islets of langerhans?
70% Beta
20% Alpha
How is the pancreas formed?
2 buds extend from the primitive duodenum at the junction of the foregut and midgut. These fuse forming the pancreas and bile duct system.
Why is the pentose pathway important?
To make NADH for reductive biosynthesis and nucleotides for the formation of ribose-5-phosphate in DNA and RNA.
What is the commitment step in the pentose pathway?
Dehydrogenation of G6P
Where is the insulin tyrosine kinase receptor primarily found?
Liver, striated muscle and adipocytes
Where would you find SGLT-1/2?
Intestinal mucosa and kidney tubules (LOH-1) (PCT-2)
What is special about GLUT-2 and where is it found?
Liver, pancreatic beta cells, SI, kidney
it is bidirectional and so uptakes glucose in glycolysis and releases it in gluconeogenesis
Where is preproinsulin synthesised?
ER
In the fed state what effect does insulin have on the Liver?
It increased glucokinase and glycogen synthase activity
In fed state what effect does insulin have on the muscles?
Increased GLUT-4 and glycogen synthase
In fed state what effect does insulin have on adipose?
Increases GLUT-4, acetyl CoA carboxylase and lipoprotein lipase
What does the [urinary glucose] tell us about kidney function?
Renal threshold has been reached, SGLT-2 fully saturated. Or infection or renal failure.
How does Cortisol affect insulin?
It is in response to stress but affects transcription and so its affect is at gene expression level, it takes time.
What is the [glucose] in hyperglycaemia?
> 13.9mmol/L
What enzyme is used in blood glucose monitoring systems and clinistixs?
Glucose oxidase
What treatment is there in diabetic ketoacidosis?
Supportive treatment: NG tubes, antiemetics
Hypovolaemia: Give IV fluids
Insulin deficient: Give IV insulin
Hypokalemia: Give IV potassium
What are some risks of Hyperosmolar hyperglycaemic state?
Cerebral pontine myelinolysis and cerebral oedema
What affect does GH have on its taregets?
Liver: IGF-1 release
Long bones: cartilage growth (Chondrocyte replication)
Muscles: incorporation of aa and protein synthesis
Adipose: Lipolysis and fatty acid release
What causes acromegaly?
Excess GH (& IGF-1) usually due to a pituitary adenoma
What tissues can regulate plasma T3 synthesis
Liver, spleen, kidney
What happens if there is an increase in Na in the blood in the brain?
Osmotic demyelination syndrome
What is adrenal crisis
Medical emergency when there is severe adrenal insufficiency - hyponatreamia, hyperkalaemia, hypoglycaemia
