INTRASPINAL SENSORY GANGLIONIC CELLS AND THEIR GENETIC SIGNIFICANCE(RSUM)
- VernacularTitle:人类脊髓内的感觉细胞及其发生的意义
- Author:
Yuquan ZANG
;
Xu ZANG
;
- Publication Type:Journal Article
- From:
Acta Anatomica Sinica
1959;0(Z1):-
- CountryChina
- Language:Chinese
-
Abstract:
The lumbosacral cord of a 55-day baby girl was cut serially and stained for a microscopicstudy.It was twice split into two with extensive dysplasia in its dorsal parts.Numerous primarysensory cells were strewn within the cord.The present study was particularly concerned with theirclassification,distribution and derivation.In addition to their normal sites,the sensory ganglionic cells are scattered on the dorsal aspectsof the cord,along the space between the separated cords,in the openings of the anterior and posteriormedian fissures and also within the crevices inside the cord,yet communicating to the outside.Such sensory elements are surrounded with capsular cells;this is also characteristic of a few sen-sory cells slightly sunken into the intramedullary structures in continuation with the heterotopicganglionic formations.A number of the sensory cells are deeply embedded in the supernumerary gray and white for-mations chiefly in the dorsal portions;they are especially numerous in the anterior gray commissureand the anterior horn.Such cells are devoid of a capsule.In the early embryonic period,unfavorable conditions retard the mutual approximation of theneural folds and the precocious ectomesenchyme thrusts itself between them.The dorsal edges ofthe folds are then forced to bend ventrally toward the neural plate,resulting in a duplication of thespinal cord.During the rolling-in process,the irregular margins of the neural folds and the out-thrusts ofthe ectomesenchyme conjoin to produce the supernumeraray structures in the dorsal portions of thecord.Some presumptive sensory elements on the folds may be roiled into such intramedullary unitsand grow up in situ.The neural crest represents the spear-head of the rollingin fold;its presumptive sensory ele-ments may well disperse themselves into the precursory anterior gray commissure and theanterior horn.The primarys sensory cells and the capsular cells are both derived from the ectoderm.Theformer bear capsular cells in case they have participated in the process of ganglion formation;whereas they lack such a capsule if they grow up right in their erratic sites.The intraspinal sensory ganglionic cells are chiefly derived from the neural crest;this doesnot exclude the tube wall as being another possible source.Though erratic in postion,the intraspinal sensory cells may perform a fairly normal function.
