is a condition characterized by abnormally low blood glucose levels, usually less than 70 mg/dl that may induce symptoms or signs such as altered mental status and/or sympathetic nervous system stimulation. (ADA )
is a clinical situation characterized by a reduction in plasma glucose concentration to a level that may induce symptoms or signs such as altered mental status and/or sympathetic nervous system stimulation
2. :Objectives
• Define hypolgycemia (Whipple’s triad).
• State the reference range for plasma glucose and describe the endocrine control of plasma glucose
concentration.
3. Define hypolgycemia (Whipple’s triad).
is a condition characterized by abnormally low blood glucose levels, usually less than 70 mg/dl that may
induce symptoms or signs such as altered mental status and/or sympathetic nervous system
stimulation. (ADA )
is a clinical situation characterized by a reduction in plasma glucose concentration to a level that
may induce symptoms or signs such as altered mental status and/or sympathetic nervous
system stimulation
4. Whipple's triad A combination of three clinical features that indicate the presence of an
insulinoma:
• presence of symptoms of hypoglycemia
• A low plasma glucose measured at the time of the symptoms
• Relief of symptoms when the glucose is raised to normal.
6. State the reference range for plasma glucose
• Reference ranges are as follows:
• Fasting plasma glucose: 70-99 mg/dL
• Postprandial plasma glucose at 2 hours: Less than 140 mg/dL
• Random plasma glucose: Less than 140 mg/dL
7. • Values for diabetes mellitus are as follows:
• Fasting plasma glucose: Greater than 126 mg/dL
• Random plasma glucose: Greater than 200 mg/dL
• Postprandial glucose at 2 hours: Greater than 200 mg/dL
• The value for hypoglycemia is as follows:
• Value less than 60 mg/dL
8. describe the endocrine control of plasma glucose concentration.
• There are two categories of endocrine influences.
a) Hormone which will decrease the blood glucose levels :
Insulin
b) Hormones which will increase the blood glucose levels:
Glucagon, Epinephrine, Cortisol, Growth Hormone (GH).
10. Factors increasing the secretion of insulin:
1. Glucose – Most potent stimulator of insulin secretion.
2. Gastrointestinal hormones:
Gastrin, Secretin, Pancreozymin.
3. Protein and aminoacids: Leucine and Arginine
4. Beta adrenergic and parasympathetic stimulation.
5. Glucagon and Growth hormone
6. Drugs: Tolbutamide
7. Incretin hormones: These hormones work to increase insulin secretion.
Examples (GLP) (GIP)
Factors decreaingthe secretion of insulin:
1. Epinephrine –
During stressful and during exercise, adrenal medulla releases adrenaline.
This suppresses insulin release and mobilizes glucose from liver for energy purpose.
2. Alpha adrenergic stimulation.
11. • Fat metabolism – Lipogenesis (+)
Lipolysis (-)
• Protein metabolism - Amino acid uptake by cells(+)
Protein synthesis (+)
Protein catabolism (-)
• Carbohydrate metabolism – Glycolysis (+)
Gluconeogenesis (-)
Glycogenesis (+)
Glycogenolysis (-)
12. Glucagon
Glucagon Release from the alpha Cells.
:Increases blood glucose concentration, i.e. Hyperglycemic Effects
Breakdown of liver glycogen (glycogenolysis)
Can cause blood glucose to double within a few minutes
Increase gluconeogenesis in the liver
Increased uptake of amino acids which are then used to make glucose
:Regulation of Glucagon Secretion
• Blood glucose – most potent regulator
• Increased amino acids in the circulation
• Especially arginine and alanine
• Catecholamines
• Gastrointestinal hormones (cholecystokinin, gastrin, GIP)
• Glucocorticoids
• Sympathetic and parasympathetic stimulation
• Exercise
13. Epinephrine
epinephrine keeps certain body tissues, such as muscle, from using as much glucose from the bloodstream, and
it acts to reduce insulin secretion.
Epinephrine is the same “fight or flight” hormone that revs the body up in response to danger, and it produces the symptoms
that normally
In some cases, especially when glucagon and epinephrine fail to adequately raise blood glucose levels, the body releases
cortisol and growth hormone, which can also increase blood glucose levels.
– The second early response hyperglycemic hormone.
– Epinephrine causes glycogenlsis , gluconeogenesis , Lipolysis
– It also stimulates glycolysis in muscle
14. •
increases gluconeogenesis,
decresases peripheral utilization of glucose,
inhibits glycolysis
Growth Hormone (GH)
• Increased liver glucose 6 phosphatase activity
• Prevents peripheral utilization of glucose by inhibiting
phosphorylation.
• Antiinsulinic effect on peripheral tissues- adrenal diabetes
• Thus leads to hyperglycemia
facilitate glucose production and limit glucose utilization, but neither of them plays a critical role. Their
effects are not immediate (delayed for about 6 hours); thus, they are mostly involved in defense against
prolonged hypoglycemia
cortisol
