05.Adipose.pdf

Specialized connective tissue Adipose tissue It is a connective tissue specialized in storing fat. Its main cells are adipocytes, which can be of two types, originating two types of adipose tissue: • White or unilocular adipose tissue • Brown or multilocular adipose tissue Adipocytes are c...

Specialized connective tissue Adipose tissue It is a connective tissue specialized in storing fat. Its main cells are adipocytes, which can be of two types, originating two types of adipose tissue: • White or unilocular adipose tissue • Brown or multilocular adipose tissue Adipocytes are cells that are derived from mesenchymal cells and participate in the synthesis and storage of triglycerides. White or unilocular adipocyte - They are large spherical cells that become polyhedral when they accumulate in adipose tissue. - They store fat constantly in the form of a single drop that displaces all the cytoplasmic content and the nucleus towards the periphery. - They have hormone receptors in their membranes that will influence the formation of fat or the release of fat from the adipocyte: insulin, growth hormone, noradrenaline and glucocorticoids. Brown or multilocular adipocyte - They are smaller and more polygonal cells than the white ones. The fat is stored in the form of multiple small drops of fat. The nucleus remains rounded in the center of the cell. Abundant mitochondria. White adipose tissue: • Composed mainly of white adipocytes • Also presents macrophages, mast cells, fibroblasts and lymphocytes • Scarce ECM • Abundant vascularization and innervation • It accumulates mainly in the subcutaneous tissue in different regions depending on the sex and age of the individual. Functions • Mechanical protection • Thermal isolation • Organs trophic support • ENERGY RESERVE Deposit and usage of fat • Dietary intake • Energy expenditure • Nervous control • Hormonal control Brown adipose tissue: • Composed mainly of brown adipocytes • Also presents adipoblasts (preadipocytes), macrophages, mast cells, fibroblasts and lymphocytes • Scarce ECM and fibers • Abundant vascularization and innervation • Especially present in newborns and hibernators. • In the human adult only found around large vessels • Helps maintain body temperature thanks to the number of mitochondria present in these adipocytes