Diabetes pt 1 Flashcards
what are incretins
polypeptides released by the gut wall during glucose absorption
the transition from prepro-insulin to proinsulin is called what
mRNA transcription in the beta cell
what is glucogenesis
converting glucose into glycogen
where do VLDLs come from
the liver
insulin stimulates the hydrolysis of what two molecules
VLDLs and chylomicrons
what is lipogenesis
the synthesis of triglycerides via glycerol and fatty acids
name some insulin modulators
glucocorticoids
growth hormone
cytokines
gut hormones
neuropepties
how does insulin exist in dilute solutions
as a single molecule (monomer)
what are the microvascular complications with T1 diabetes
nephropathy
neuropathy
retinopathy
What is C-peptide
a byproduct of insulin production in the pancreas
what is the most robust association between inherited suscepitbility for T1d
polymorphisms in HLA
what is lipolysis
triglycerides broken down into glycerol and fatty acids
How do FFA and insulin react
ffa interfere with the actions of insulin and cause insulin resistance
do you need insulin for T2d
no, you can survive without it
where does preproinsulin becomes proinsulin
Rough ER
what part of the beta cell secretes insulin
the beta cell core
what is lipolysis stimulated by
catecholamines
glucagon
cortisol
growth hormone
thyroxine
what cells secrete glucagon
alpha cells
what do incretins inhibit
stomach emptying during meals to slow glucose absorption
how does insulin play a part with proteins
it stimulates protein formation and inhibits breakdown
are islets of langerhaans richly or poorly innervated
richly
what is the major source of the glycerol backbone
glucose
how are the A and B chains of insulin connected
by two disulfide bridges
what does the beta cell core do
secretes insulin into blood vessels which perfuse the outer islet
what is HLA
human leucocyte antigen
Is C-peptide detectable in T1D
nope
when does glucose act on beta cells
when food is absorbed in the SI
where does insulin from the beta cell go after it is secreted
into blood vessels which then perfuse the outer islet
what glut receptor is used for the CNS
(CHO metabolism)
glut 1
what does insulin stimulate in muscle tissue (CHO metabolism)
translocation of glut4 receptors to membrane
glycogenesis
glycolysis
what are the two kinds of incretins
GLP-1
GIP
where does the cleavage of proinsulin occur
secretory granule of insulin
increase in catecholamines in muscle causes what
glycogen breakdown - availability of glucose
what is the primary stimulus for insulin secretion
glucose
what is the honeymoon period with T1 diabetes
a temporary remission in some people
what is the macrovascular complications with T1 diabetes
ischemic heart disease
what do catecholamines do in skeletal muscle (CHO metabolism)
triggers disintegration of glycogen
where does the pancreas venous drainage go
into the portal vein
what cells secrete insulin
beta cells
what can happen to your muscles with a lack of insulinq
increased protein breakdown and decreased muscle mass (sarcopenia)
Is C-peptide detectable in T2D
yes
what three molecules are used during gluconeogenesis
lactate
amino acids
glycerol
under normal circumstances, how does the secretion of insulin occur
2 phases
1) rapid, readily releasable pool
2) extended, reserve pool
what is the storage form of glucose
glycogen
what is gluconeogenesis
glucose is made from non-glucose molecules
what is gluconeogenesis inhibited by
insulin
what is sarcopenia
decreased muscle mass
what does insulin inhibit
catabolic processes
when does glucose act on incretin release
when food is being digested in the stomach
what phase of secretion is lost in t2d
the first phase - rapid
abdominal fat may release more of what into the portal vein
FFA
what processes does insulin regulate in adipose tissue
(CHO metabolism)
glycolysis
glyceroneogenesis
glycogenesis
lipogensis
What is different about GLUT 4 from 1-3
it is insulin DEPENDANT
what two things aid glycogenolysis in skeletal muscle
(CHO metabolism)
catecholamines
glucagon
what is GLP-1
glucagon-like peptide 1
where do catecholamines play a part with glucose
muscle
what is t2d characterized by
high fasting glucose
glucose intolerance
how many aa in the A chain of insulin
21
what do PP cells secrete
pancreatic polypeptide
where is GIP released from
the upper gut - duodenum
where are all the beta cells
in the islet core
what chain of insulin has 21 aa
A chain
what glut receptors are found in skeletal muscle
(CHO metabolism)
glut 1
glut 4
name 5 things that lipolysis is stimulated by
catecholamines
glucagon
cortisol
growth hormone
thyroxine
what chain of insulin has 30 aa
B chain
what does insulin stimulate in adipose tissue (CHO metabolism)
glucose uptake (glut 4)
glycolysis and glycogenesis
glucose to fatty acids
lipogenesis
what is glycolysis
the breakdown of glucose into pyruvic acid (first step of cellular respiration)
where does GLUT 4 reside
in the cytoplasm of the cell, unless triggered to the cell membrane by insulin or excersize
what does pancreatic polypeptide do
inhibits pancreatic secretion
inhibits gastric emptying
what are islet cell antibodies
a specific predictive marker for t1d
where is GLP-1 releasedd
from the sital bowel
where do chylomicrons come from
the gut
somatostatin inhibits:
insulin
glucagon
what two things trigger glut 4 to come to the membrane
insulin and exercise
what processes does insulin regulate in skeletal muscle
(CHO metabolism)
glycolysis
glycogenesis
glycogenolysis
what secretes somatosotatin
delta cells
what role do class 2 HLAs play in your immune system
present foreign and self antigens to T cells - start the autoimmune process
where is the body of the pancreas
behind the stomach and the tail touches the spleen
what does insulin promote
anabolic processes of enzymes
what is the cause of t2d
impaired insulin secretion and tissue insensitivity to insulin
what glut receptors are used in adipose tissue
(CHO metabolism)
glut 1
glut 4
how does insulin exist in concentrated solutions
6 insulin molecules
2 zinc ions form a hexamer
aka 3 dimers of insulin
Describe how glucagon acts on the liver
Gluconeogenesis UP
Glycogenolysis UP
Glycolysis DOWN
Glycogenesis DOWN
aka does anything to increase glucose in the blood stream
where does the secretory granule formation of insulin form
golgi appartaus in the beta cell
what two things stimulate glycogen breakdown/gluconeogenesis
glucagon
catecholamines
name 4 nutrients that increase insulin secretion
glucose
long chain fatty acids
ketone bodies
amino acids
how many aa in the B chain of insulin
30
insulin inhibits:
glucagon
is ketoacidosis present with t2d
no
what do incretins stimulate during hyperglycemia
the release of additional insulin
how can an absence of infections cause t1d
a lack of interaction with pathogens is an important way of educating the immune system and promoting self tolerance
how are abdominal and subcutaneous fat different
abdominal fat are more sensitive to lipolytic stimuli
where is the head and neck of the pancreas
tucked in hte C-shaped curve of the duodenum
what is GIP
glucose-dependant insulinotropic polypeptide
what is glycogenolysis
the break down of glycogen into glucose
how does non-alcoholic fatty liver disease occur
ffa are released in increased amounts into the portal vein and are accumulated in the liver
What does IDDM stand for
Insulin-dependant diabetes mellitus
when does glucose act on gustatory sensory mechanisms that stimulate a CPIR
when food is being chewed and swallowed
what do delta cells secrete in the pancreas
somatosotatin
where is the pancreas
upper portion of posterior abdominal wall
what does somatostatin do
inhibits the release of pancreatic hormones
also reduces gastric secretions
what secretes pancreatic polypeptide
PP cellsw
what type of diabetes has more common microvascular complications
t1d
