Endo 5 Flashcards
What do the alpha cells in the pacreas make?
insulin
Glucagon? - Molly
What do the beta cells in the pancreas make?
insulin?
What do delta cells in the pancreas make?
somatostatin
What does somatostatin do in the pancreas?
inhibit the secretion of insulin and glucagon
How much of the pancreas is for endocrine function?
1%
What are the islet of langerhans?
groups of cells in the pancreas that are made of alpha, beta, and delta cells
What is insulin secretion associated with?
energy abundance
What is insulin composed up>
two amino acid chains, connected by disulfide bonds
How does insulin circulate?
mostly unbound
-relatively short half life
What digestive hormones work to stimulate insulin?
incretin
What is the sulfonylurea receptor?
a potassium transport channel that moves K out of the cell that closes when glucose enters the cell to help release insulin
What are the steps of insulin release?
-glucose enters the cell
-the glucose is metabolized and ATP is made
-ATP sensitive K channels close (sulfoynurea)
-the cell depolarized
-Ca channels open
-there is an exocytosis of insulin
What is ozempic?
GLP-1 agonist
-causes increased secretion of insulin
What are insulin and glucaogon?
antagonists
Is insulin stored prior to being needed?
yes
-however after the storage runs out, the body makes more insulin
When blood glucose increases, what hormone increases?
insulin
What is normal fasting blood glucose?
80-90 mg/100ml
When blood glucose decreases, what hormone increase?
glucagon
What type of receptors does insulin bind to on the receptor/
tyrosine kinase receptors
What is the fast response of insulin?
increase glucose uptake, especially by muscle cells and adipocytes due to translocation of vesicles containing GLUT-4 to the membrane
What does the movement of GLUT-4 to the membrane cause?
cause the membrane to become more permeable to amino acids, potassium, and phosphate ions
What is the slower response of insulin binding to the tyrosine kinase receptors?
change in enzyme activity leading to changes in metabolism
-the enzyme activity caused by the phosphorylation
What is the slowest response of insulin binding to tyrosine kinase receptors?
changes in gene expression and growth
-allow the cell to make more protiens
What are the effects of insulin in muscles?
Overall- promotes muscle glucose uptake and metabolism-anabolic effect
- insulin increases movement of glucose into the cell
-increases glycogen storage in muscle
-increase protein synthesis and inhibit protein degradation
What are the effects of insulin on protein metabolism and growth?
Overall- promote protein synthesis and storage inhibits protein degradation
- insulin and GH work synergistically to promote growth
What are the effects of insulin on the liver?
Overall- insulin promotes the uptake and storage of glucose as glycogen in the liver
-increase glucose uptake
-increase glycogen synthase
-decrease breakdown of glycogen by inhibiting liver phosphorylase
-promote conversion of excess glucose into free fatty acids
What are the effects of insulin on fat metabolism?
overall- promote fat synthesis and storage
-glucose enters the adipocyte
-activate lipoprotein lipase
-splitting triglycerides into fatty acids to enter the cell
-become triglycerides to be stored
What does a lack of insulin do to fat?
increase lipolysis
-release free fatty acids that will lead to ketoacidosis
What happens in the plasma when there is insulin?
decrease glucose
decrease free fatty acid
decrease ketoacids
decrease amino acids
What increases insulin secretion?
-increased blood glucose
-increase blood FFA
-increase blood AA
-GI hormones (incretin)
-glucagon, GH, cortisol
-PNS stimulation
-SNS
insulin resistance
-sulfonylurea
What decreases insulin secretion?
-decrease blood glucose
-fasting
-somatostatin
-alpha adernergic activity
-leptin
What is glucagon?
hormone of starvation
What is the primary target tissue for glucagon?:
liver
-want to increase blood glucose by
* stimulating glycogenolysis
* stimulate gluconeogenesis
* increase blood fatty acids and ketoacid levels
What is diabetes mellitus?
metabolic disorder characterized by hyperglycemia due to insufficient insulin or cellular resistance to insulin or both
What is hypoinsulinemia?
type I diabetes
What is hyperinsulinemia?
type II diabetes
What are symptoms of diabetes mellitus?
-polyuria
-polydipsia
-polyphagia
-extreme fatigue
-blurry vision
-cuts/bruises slow to heal
-weight loss even though you are eating more (type I)
-tingling, pain, or numbness in hands/feet (type II)
What is the normal fasting glucose?
100 mg/dl
What is the fasting glucose of prediabetes?
100-125 mg/dl
What is the fasting glucose of diabetes?
126 mg/dl or above
What is the 2-h PG of a healthy person?
140 mhg/dl
What is the 2-h PG of prediabetes?
140-199 mg/dl
What is the 2-h PG of diabetes?
over 200 mg/dl
What is the A1C of a healthy person?
less than 5.6%
What is the A1C of a prediabetic person?
5.7-6.4%
What is the A1C of someone with diabetes?
above 6.5%
What is the pathophysiology of DM type I?
-autoimmune destruction of pancreatic beta cells
-5-10% of DM cases
-formerly called juvenileonset diabetes or insulin dependent diabetes
What are the risk factors of DM type I?
-genetic predisposition-increases susecptibility
-environmental triggers stimulate autoimmune response
-usually develop younger than the 40 years old
What does hyperglycemia lead to?
-polyuria
-polydipsia
-polyphagia
-glucosuria
-weight loss
-malaise and fatigue
-hyperkalemia
What does insulin do to Na/K pump?
increase the activity
What causes ketoacidosis?
-increased lipolysis to fatty acids
-infection
-pregnancy
-pheochromocytoma
-cushings syndrome
-major trauma
-surgery
What is DKA a response to?
cellular starvation brought on by relative insulin deficiency
What is the pathophysiology of DKA?
-osmotic diuresis
-dehydration
-metabolic acidosis
-fluid and electrolyte imbalances
Signs and symptoms of DKA?
-fruity breath
-nausea/abdominal pain
-dehydration
-tachycardia (increase SNS)
-lethargy
-coma
-polydipsia, polyuria, polyphagia
-kussmaul respirations (blow off CO2 to reverse acidosis)
What does acidosis do to neuronal activity?
decreases neuronal function
-blocks inward current of Na and Ca
What are risk factors of DM type II?
-history of diabetes in family
-obesity
-physical inactivity
-race/ethnicity
-women
-patients with hypertension
What is the pathophysiology of Type 2 DM?
hyperinsulinemia due to insulin resistance (early)
-beta cell dysfunction due to possible exhaustion (late)
-down regulation of inulin receptors in target tissue and insulin resistance
Examples of metabolic syndromes:
-obesity
-insulin resistance
-fasting hyperglycemia
-lipid abnormalities
-hypertension
What are chronic complication of DM?
-retinopathy
-nephropathy
-neuropathy
-vascular disease
-myopathies
What are oral manifestations of DM?
-periodontal disease
-salivary and taste dysfunction
-oral bacterial and fungal infections
-oral mucosa lesions
-diminished salivary flow and burning mouth syndrome
-delayed mucosa wound healing
-xerostomia in patients on oral hypoglycemia agents
What does periodontal disease do to diabetes?
periodontal disease exacerbates diabetic complications
-poor glycemic control
-cardiovascular complications
