Epsilon cell Epsilon cell Epsilon cells (ε-cells) are endocrine cells found in the Islets of Langerhans and produce the hormone ghrelin. They were discovered in mice. In human fetal pancreases, single epsilon cells scattered in primitive exocrine tissue were observed to start aggregating into clusters after gestational week 13. From gestational week 21, epsilon cells were observed around developing islets, forming an almost continuous layer at the rim of the islets. In adult pancreas samples, they remained localized on the mantle of the islets in different amounts. Production of ghrelin with insulin, glucagon, or somatostatin was not detected during development. Co-production with
Composition of the human body Not all elements which are found in the human body in trace quantities play a role in life. Some of these elements are thought to be simple bystander contaminants without function (examples: caesium, titanium), while many others are thought to be active toxics, depending on amount (cadmium, mercury, radioactives). The possible utility and toxicity of a few elements at levels normally found in the body (aluminium) is debated. Functions have been proposed for trace amounts of cadmium and lead, although these are almost certainly toxic in amounts very much larger than normally found in the body. There is evidence that