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Published on: April 20, 2017
The effect of alanine on glucagon secretion
The Journal of Clinical Investigation
|October 1, 1971
Summary
Alanine infusion stimulates pancreatic glucagon secretion in fasting dogs, suggesting glucagon mediates gluconeogenesis from amino acids. This effect is abolished when glucose is readily available.
Area of Science:
- Endocrinology
- Metabolic Regulation
- Physiology
Background:
- Glucagon is a key hormone in glucose metabolism.
- Alanine is a primary precursor for gluconeogenesis.
- The hormonal regulation of gluconeogenesis by glucagon is not fully understood.
Purpose of the Study:
- To investigate if alanine stimulates glucagon secretion.
- To determine the role of glucagon in alanine-induced gluconeogenesis.
- To assess the influence of glucose availability on alanine's effect on glucagon.
Main Methods:
- Infusion of alanine into conscious dogs.
- Measurement of plasma glucagon and insulin levels using radioimmunoassay.
- Induction of hyperglycemia via intravenous glucose infusion.
Main Results:
- Alanine infusion significantly increased pancreatic glucagon levels in fasting dogs.
- Insulin and glucose levels showed minimal changes during alanine infusion alone.
- Alanine-induced glucagon secretion was suppressed during hyperglycemia.
Conclusions:
- Alanine stimulates glucagon secretion in the fasting state.
- Glucagon may act as a humoral mediator for gluconeogenesis from endogenous alanine.
- The stimulatory effect of alanine on glucagon is dependent on glucose availability.
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