The cytoplasm of pancreatic beta cell contains numerous dense core secretory granules which are all positive for insulin as detected by immunohistochemical stains, which are insulin-containing secretory granules.

Hi Amal,

If we observe the beta cells under th electron microscope we can see different density of the secretory granules, some of them will be more dense and some of them will be less dense. Highly dense vesicles are mature granules with insulin fully synthesized and about release when there is an increase in blood glucose levels as per the signaling and sensing, where as less dense granules are on the way to synthesis and manturation.

In general beta cell control insulin but activity time it will be secret some insulin