What are Islets of Langerhans
Cell types? (4)
Exocrine pancreas makes what enzymes?
Islets of Langerhans: clusters of endocrine cells interspersed among the acinar groups (that make up the exocrine pancreas.
Beta: 70% insulin
Alpha: 20% glucagon
Delta: 10% somatostatin
PP 1-2% pancraetic polypeptide
What is it?
what is it's main pathology/effect?
Leading cause of what disease?
Group of metabolic disorders resulting in hyperglycemia due to defects in insulin secretion, insulation action or both.
Vasculopathy: with long-term complications involving the kidneys, eyes, nerves and blood vessels.
21 million americans affected
leading cause of ESRD (endstage renal disease, blindness and amputation.
Classification of Diabetes
Type 1: aka juvenile, insulin dependent, 10% of cases, severe insulin deficiency.
Type 2: aka adult onset, non-insulin dependent. Peripheral resistance to insulin action and inadequate response to insulin secretion by Beta cells.
Presenting symptoms of DM Type 1
what is the main/worse symptom.
usually presents by age 35
polyphagia with weight loss
Ketoacidosis: fat is primary energy source, excess ketones produced because of fat metabolism, decreases blood pH can lead to diabetic coma.
Presenting symptoms of DM type 2
Usually presents after age 40
Polyuria and polydipsia may occur
diagnosis made after routine blood tests
enhanced susceptibility to infection: periodontal disease
Laboratory diagnosis of Diabetes Mellitus:
Normal glucose range
DM indicated if...
Blodd glucose concentration is higher than?
Fasting glucose is greater than?
Blood glucose is greater than ___ with in 2 hours of ingesting 75g of glucose.
Normal glucose is 70-120mg/dL
Random blood glucose concentration of 200mg/dL or higher
Fasting glucose greater than 126mg/dL on more than one occasion.
Blood glucose greater than 200mg/dL within 2 hours of ingesting 75g of glucose.
Etiology of Type 1 Diabetes Mellitus:
Absolute lack of insulin secondary to autoimmune destruction of B-cells
Patients require insulin from outside sources to survive.
Etiology of Type 2 Diabetes Mellitus:
Multiple genes play a role: each has its own risk and modified by the environment.
peripheral tissues cannot respond properly to insulin (insulin resistance)
B-cell dysfunction: inadequate insulin secretion in the face of insulin resistance and hyperglycemia.
Disposing factors to Type 2 Diabetes Mellitus:
3 main ones
1. Obesity: 80% are obese, 60% exhibit glucose intolerance, adipose tissue appears to be antagonistic to insulin.
Manifestations of DM
what is the big problem/effect of DM?
what are the affects on the pancreas?
Vasculopathy: Big thing is vascular disease, occurs because of sugar problems. Responsible for 80% of DM-related deaths. Atherosclerosis, MI, gangrene of lower extremities, thickend basement membrane, especially around small blood vessels (MICROANGIOPATHY)
Pancreas: destruction of islets of langerhans, heavy inflammatory infiltrate, amyloid.
Manifestations of DM on the Kidneys?
rank of cause of death?
2nd leading cause of death behind vaculopathy
Diffuse glomerulosclerosis: 90% of diabetics within 10 years, not specific to diabetics, microangiopathy around glomerular capillaries and depsotion of matrix. Proteinuria, total renal failure.
Nodular glomerulosclerosis: 35% specific to diabetics, ball-like deposition of matrix, total renal failure.
Mainfestations of DM to the eye?
4th leading cause of blindness
Microangiopathy and microaneurysms
Retinal detachment and vision loss.
Islet Cell Tumors:
What part of the pancreas is affected?
Most are from the exocrine pancreas.
May be functional or non-functional
Gastrinoma: 90-95% of patients with really bad peptic ulcers.
What is Zollinger-Ellison Syndrome?
Pancreatic islet cell tumor, hypersecretion of gastric acid causing severe peptic ulcers. 60% malignant.
Islet Cell Tumors:
What is Insulinoma?
Insulinoma (Insulin secreting Islet Cell tumor)
Insulinoma: B-cell tumor, hyperinsulinism, most are adenomas. Hypoglycemia quickly occurs from fasting or exercise. Many are asymptomatic, 5-10% malignant. Nervousness, confusion, stupor. Tx: Surgical excision.
Adrenal Cortex: 3 zones, what they secrete
Adnreal Medulla: what it secretes
zona glomerulosa: mineralcorticoids (aldosterone)
zona fasciculata: glucocorticoids (cortisol)
zona reticularis: sex hormones (estrogen/androgen)
Adrenal Medulla: neural origin, chromaffin, source of catecholamines (epinephrine).