[Myeloarchitectonics of visceral nerves during human ontogeny]

In transversal electively stained histological sections of the vascular-neural complexes of the nephric ovarian, proper hepatic, common carotid, femoral arteries neural trunklets were counted, their diameters were measured, myelin fibres were divided into thin, middle and thick groups. In mature persons, the number of the neural trunklets (including those of microscopic diameter) in every paravasal plexus is greater than in newborns and in old persons. Total number of the myelin fibres, in mature persons, is greater than in newborns: in nerves of the ovarian plexus 13, in nerves of the nephric plexus 4.5, in nerves of the hepatic plexus 2.5, in nerves of common carotid artery 6, in the femoral artery 1.5 times as great in the former than in the latter. In old persons total number of myelin fibres grows smaller comparing to those in mature persons. The thick and middle fibres (their part is maximal in mature persons) undergo resorption to a greater extent than the thin ones in the nerves of old persons. In the individuals of the same age group, as well as in separate groups, the total number of myelin fibres varies within a wide range. As quantitative factors demonstrate, the definitive ensemble of the myelin conductors mature asynchronously in nerves of different organs. Difference in quantitative and qualitative contents of the myelin component reflect certain specificity of the conductive link of innervation, peculiar for each organ at every stage of the individual development.