The specificity of the epithelial mesenchyme inductive relations in the morphogenetic synergisms algorithm inside branched tube-alveolar and tube-acinar systems

he genesis and 3D evolution of the dichotomic branching structures are of interest for the fundamental as well as for the applicative research. The study of the ‘epithelial type’ branching models that is characteristic to some organs remains a partially explored field [1]. We selected two anatomic and functional systems for the study of the epithelial mesenchyme inductive interactions: the bronchopulmonary and the salivary glands systems. Two phenomena brought our attention during the ontogenesis of those two systems: first of all, the particularities of the morphogenesis and differentiation processes that involved the tube-like structures, and second, the determinant mechanism that leads to functional specialized structures – the blood air barrier inside the pulmonary respiration system and the glandular acinus inside the salivary glands’ secretion system. During the morphogenesis processes, an important role is played by the mesenchyme that is responsible for the regional specificity of induction inside competent structures [2, 3]. In the algorithm of the pulmonary respiration system morphogenesis, this specificity is spectacular [4]. Structural heterogeneity of organs containing dichotomized branching elements leads to problems in understanding their architectural mechanisms of ontogenesis on one side, as well as of evaluating the evolution status in normal and pathologic conditions on the other side, such as: • What are the elements or structures that interact in the algorithm of morphogenetic synergisms? • What are the rules to ratify the stages of formation for the branched structures? • What are the consequences of the epithelial mesenchyme inductive relations? • What are the mechanisms for epithelial mesenchyme inductive relations? • How is it possible, the growing and dichotomy branching of the epithelial buds inside the tubealveolar and tube-acinary systems? • What are the means of inductive interactions?

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