islets of Langerhans

(noun)

Regions in the pancreas that contain its endocrine cells.

Related Terms

Examples of islets of Langerhans in the following topics:

  • Types of Cells in the Pancreas

    • The islets of Langerhans are the regions of the pancreas that contain many hormone-producing endocrine cells.
    • The light-stained clusters of cells are called islets of Langerhans, which produce hormones that underlie the endocrine functions of the pancreas.
    • Alpha cells that produce glucagon, and make up 15–20% of total islet cells.
    • The islets of Langerhans can influence each other through paracrine and autocrine communication.
    • A porcine islet of Langerhans.

  • Overview of Pancreatic Islets

    • Pancreatic islets, also called the islets of Langerhans, are regions of the pancreas that contain its hormone-producing endocrine cells.
    • The endocrine function of the pancreas helps maintain blood glucose levels, and the structures involved are known as the pancreatic islets, or the islets of Langerhans.
    • Alpha cells that produce glucagon and make up 15–20% of total islet cells.
    • The feedback system of the pancreatic islets is paracrine—it is based on the activation and inhibition of the islet cells by the endocrine hormones produced in the islets.
    • The islets of Langerhans are the regions of the pancreas that contain its endocrine (hormone-producing) cells.

  • Histology of the Pancreas

    • The pancreas serves digestive and endocrine functions, and it is composed of two types of tissue: islets of Langerhans and acini.
    • Light-stained clusters of cells are called islets of Langerhans.
    • The part of the pancreas with endocrine function is made up of approximately a million cell clusters called islets of Langerhans.
    • Four main cell types exist in the islets.
    • The islets are a compact collection of endocrine cells arranged in clusters and cords and are crisscrossed by a dense network of capillaries.

  • Pancreas

    • These zymogens are inactivated forms of trypsin and chymotrypsin.
    • The part of the pancreas with endocrine function is made up of approximately a million cell clusters called the islets of Langerhans.
    • Four main cell types exist in the islets.
    • The islets are a compact collection of endocrine cells arranged in clusters and cords that are crisscrossed by a dense network of capillaries.
    • The capillaries of the islets are lined by layers of endocrine cells that are in direct contact with blood vessels, either by cytoplasmic processes or by direct apposition.

  • Interactions of Hormones at Target Cells

    • When conditions exceed the upper limit of homeostasis, a specific action—usually the production of a hormone—is triggered.
    • If conditions exceed the lower limits of homeostasis, a different action, usually the production of a second hormone, is triggered.
    • The regulation of blood glucose concentration (through negative feedback) illustrates how the endocrine system maintains homeostasis by the action of antagonistic hormones.
    • Bundles of cells in the pancreas, called the islets of Langerhans, contain two kinds of cells: alpha cells and beta cells.
    • The glucose in the liver originates from the breakdown of glycogen.

  • Pancreatic Islet Disorders: Diabetes and Hyperinsulinism

    • Hyperinsulinism refers to an above-normal level of insulin in the blood of a person or animal.
    • This refers to an above-normal level of insulin in the blood of a person or animal.
    • It can produce a variety of symptoms and effects but the principal problems arise from an inadequate supply of glucose to the brain, resulting in impairment of function (neuroglycopenia).
    • The most common forms of hypoglycemia occur as a complication of treatment of diabetes mellitus with insulin or oral medications.
    • Recurrent hypoglycemia may be prevented by reversing or removing the underlying cause, by increasing the frequency of meals, with medications like diazoxide, octreotide, or glucocorticoids, or by surgical removal of much of the pancreas.

  • Type 1 Diabetes Mellitus

    • Pancreatic islet cell transplantation is experimental, though growing.
    • Although the cause of this type of diabetes is still not fully understood, it is believed to be of immunological origin.
    • About a quarter of people with new type 1 diabetes have developed some degree of diabetic ketoacidosis (a type of metabolic acidosis which is caused by high concentrations of ketone bodies, formed by the breakdown of fatty acids and the deamination of amino acids) by the time the diabetes is recognized.
    • Giving children 2000 IU of Vitamin D during their first year of life is associated with reduced risk of type 1 diabetes, though the causal relationship is obscure.
    • Islet cell transplantation is less invasive than a pancreas transplant, which is currently the most commonly-used approach in humans.

  • Protection

    • The skin also contains important cells called Langerhans cells. 
    • Part of our skin is made up of fat. 
    • It acts as a food source, protecting our body from the effects of starvation.
    • All sorts of sensory receptors are found within the skin as well. 
    • Finally, the skin is also important for the synthesis of vitamin D, which is an important vitamin for the building of strong and healthy bones.

  • Structure of the Skin: Epidermis

    • This layer is one of the most important layers of our skin. 
    • Devoid of nutrients and oxygen, the keratinocytes die as they are pushed towards the surface of our skin.
    • This layer is only easily found in certain hairless parts of our body, namely the palms of our hands and the soles of our feet. 
    • They are devoid of almost all of their water and they are completely devoid of a nucleus at this point. 
    • The epidermis is made up of 95% keratinocytes but also contains melanocytes, Langerhans cells, Merkel cells, and inflammatory cells.

  • Pancreatic Cancer

    • The most common type, accounting for 95% of these tumors, is adenocarcinoma, which arises from the exocrine, or digestive, component of the pancreas .
    • A minority of pancreatic cancers arise from insulin-producing islet cells and are classified as neuroendocrine tumors, which are typically less aggressive and have a better prognosis.
    • Pancreatic cancer is the fourth most common cause of cancer-related deaths across the globe, and has one of the highest fatality rates of all cancers.
    • Symptoms of pancreatic cancer metastasis.
    • This depends on the stage of the cancer.