Insulin inhibition test
Rationale: Inhibition of endogenous insulin secretion and hepatic glucose output with drugs such as adrenaline plus propranolol or somatostatin, growth hormone release inhibitors, etc., even if islet β cells are blinded, then the subject is simultaneously infused Glucose and insulin, adjust the infusion rate to achieve steady-state plasma glucose (SSPG) and steady-state plasma insulin (SSPI). At this time, the ratio of blood glucose concentration to blood insulin concentration can be used to evaluate insulin. Sensitivity.
Basic operation method: 12 hours on an empty stomach overnight, 30 minutes after morning rest, the experiment was started: the venous passages were established on both sides of the elbow vein, and the microinfusion pump was connected on one side. First, 5 mg of propranolol was injected intravenously, and the blood was started after 5 minutes. Note a mixture of glucose (6 mg·kg -1 · min -1 ), adrenaline (6 μg / min ), propranolol (0.08 mg / min) and insulin (50 mU / min), generally 90 The homeostasis was reached after min, and then continued for 60 min, for a total of about 150 min. On the other side, blood glucose, insulin, C-peptide and growth hormone were measured every 10 minutes under steady-state conditions, and the whole test procedure was performed. Keep calm and pay close attention to life indicators such as pulse, blood pressure, and electrocardiogram. Cardiostatin or growth hormone release inhibitor (250 μg/h) can also be used instead of epinephrine and propranolol to reduce cardiovascular side effects.
Results: The SSPI concentration was about 100 μU/ml when the SSPG of normal people without insulin resistance was about 100 mg/dl; when the SSPG was significantly increased, >100 mg/dl, the body showed insulin resistance.
Applicable people: This test can be applied to all research groups.
Excerpt from: Knowing - Flying Brother talk