[The histotopographical characteristics of the muscular structures of the wall of the human esophagus in the area of the bronchial constriction].

The zone of the bronchial constriction of the esophagus and the area of the upper and lower dilatation of the esophagus was studied in humans of different age by the morphohistotopographic method at the macro- and microscopic levels. The bronchial constriction area of the esophagus was found to have a thickening of the circular layer of the muscular tunic, less relative thickness of the longitudinal layer, changed course of muscular fibers. The smooth muscle thickening of the circulating layer of the muscular tunic is localized at the boundary of the transitional zone of the displacement of the striated muscle fibers by smooth myocytes. The above morphological signs are characteristic of the areas with sphincter functions which allows to consider the bronchial constriction as a sphincter zone of the esophagus.