Which of the following is true about somatostatin, insulin, and glucagon?
## Core Concept
Somatostatin, insulin, and glucagon are hormones involved in glucose regulation. Somatostatin inhibits the secretion of several hormones, including insulin and glucagon. Insulin lowers blood glucose levels, while glucagon raises them.
## Why the Correct Answer is Right
The correct statement is that somatostatin inhibits the release of both insulin and glucagon. Somatostatin acts on the pancreas to decrease the secretion of insulin and glucagon. Insulin is released by the beta cells of the pancreas and promotes the uptake of glucose by cells, thereby lowering blood glucose levels. Glucagon, released by the alpha cells, stimulates the liver to release stored glucose (glycogen) into the bloodstream, raising blood glucose levels. By inhibiting both hormones, somatostatin has a regulatory effect on glucose metabolism.
## Why Each Wrong Option is Incorrect
- **Option A:** This option is incorrect because it inaccurately describes the relationship between somatostatin, insulin, and glucagon.
- **Option B:** This option is incorrect as it does not accurately represent the effect of somatostatin on insulin and glucagon secretion.
- **Option C:** Without specific details on the option, it's challenging to directly refute it, but given that D is correct, any statement contradicting the inhibitory effect of somatostatin on insulin and glucagon or misrepresenting their functions would be incorrect.
## Clinical Pearl / High-Yield Fact
A key point to remember is that somatostatin, also known as growth hormone-inhibiting hormone (GHIH), plays a crucial role in regulating the endocrine system by inhibiting the release of several hormones, including insulin and glucagon. This regulatory function is vital in glucose homeostasis.
## Correct Answer Line
**Correct Answer: D.**