ECTOPIA (ectopia; Greek ektopios remote, remote from the place; a synonym a heterotopy) — the shift of fabric, body or its part to the place, unusual to them. Inborn malformations are the main reason for an ectopia (see). Most often meet an ectopia of a bladder (see), an ectopia of an ureter (see), a crystalline lens (see), a small egg (see).
One of forms of the ectopia caused by primary disturbance of a differentiation of the developing fabric is the heteroplasia, e.g. shift of a mucous membrane of a stomach in mekkelev a diverticulum (see Mekkel a diverticulum), islands of a cartilage — in a gipoplazirovanny kidney. The heteroplasia should be distinguished from the metaplasia (see) arising in sites mature, the high-differentiated fabric.
The centers of a malrelated tissue can perform identical normal function. So, tissue of a mammary gland in sites of an ectopia is exposed to the same fiziol. to changes at a menstrual cycle and pregnancy, as mammary glands. Also ectopic secretion of hormones — AKTG, adrenaline, somatostatin, serotonin which is carried out by tumoral elements, first of all from group apudy is described (see APUD-system, t. 20, additional materials).
Bibliography: Davydovsky I. V. General pathology of the person, M., 1969; The General pathology of the person, under the editorship of A. I. Strukov and other. M. 1982; Ackerman L. V. Ackerman's surgical pathology, v. 1, St Louis a. o., 1981; Muir R. Muir's textbook of pathology, Glasgow, 1980; Robbins S. L., Angell M. Kumar V. Basic pathology, Philadelphia a. o., 1981.
G. A. Frank.