Sometimes friction on the skin--from clothing, for example--will cause a hair follicle to swell up. This can make the opening close up, trapping the bacteria inside and starting an infection. Boils and carbuncles often form in moist areas of the body such as the back of the neck, buttocks, thighs, groin, and armpits. If you have a chronic illness, such as diabetes or kidney or liver disease, you may be more likely to have boils and carbuncles.
Islets of Langerhans. The islets of Langerhans are the endocrine (endo= within) cells of the pancreas that produce and secrete hormones such as insulin and glucagon into the bloodstream. The pancreatic hormones, insulin and glucagon, work together to maintain the proper level of sugar (glucose) in the blood. Blood sugar is used by the body for energy. An understanding of the two functional components of the pancreas is important for two reasons.
Primary hormones secreted by the pancreas include: 1  Gastrin: This hormone aids digestion by stimulating certain cells in the stomach to produce acid. 2  Glucagon: Glucagon helps insulin maintain normal blood glucose by working in the opposite way of insulin. It stimulates your cells to release glucose, and this raises your blood glucose levels. Insulin: This hormone regulates blood glucose by allowing many of your bodyâs cells to absorb and use glucose. In turn, this drops blood glucose levels. Somatostatin: When levels of other pancreatic hormones, such as insulin and glucagon, get too high, somatostatin is secreted to maintain a balance of glucose and/or salt in the blood. Vasoactive intestinal peptide (VIP): This hormone helps control water secretion and absorption from the intestines by stimulating the intestinal cells to release water and salts into the intestines.