Autoradiographic study of histogenesis in the mouse olfactory bulb I. Time of origin of neurons and neuroglia

Abstract

Time of origin (final cell division) of neurons and neuroglia of the mouse olfactory and accessory olfactory formations was determined by autoradiography. Animals were injected with thymidine-H3 at various developmental stages and killed at or near maturity. In the olfactory formation mitral cells (the largest neurons) arise first, mainly over the three day period from the eleventh day of gestation ( E l l ) to E13, tufted cells chiefly from E l 3 to E18, and granule cells (the smallest neurons) mainly from E l 8 to postnatal day 20. Most of the smaller and more superficial peripheral tufted cells arise later than the deeper and larger middle and internal tufted cells. All three types of granule cells have a time of origin extending well into postnatal life, with internal granule cells arising over a longer and later period than periglomerular cells or granule cells of the mitral cell layer. Neuroglial precursors undergo final cell division chiefly between E l 7 and P10. In the phylogenetically less evolved accessory olfactory formation, mitral cells originate earlier than their homologues in the olfactory formation; mitral cells principally from E l 0 to E l 2 and granule cells chiefly from E l 2 to E18. The results support the concept that some germinal layers of the central nervous system are programmed to produce a succession of cell types, larger cells before smaller ones.

General organization of the perinatal and adult accessory olfactory bulb in mice

“…4E and F). As similar differences in the immunoreactivity were observed in adults (results not shown) and neurogenesis of AOB precedes that of the MOB (Hinds, 1968a;Brunjes and Frazier, 1986), it suggests that the low density in the VNNL and GlL of the AOB is not related to age but to the peculiarities in the organization of the mentioned layers.…”

“…By means of autoradiography, at the time an innovative technique, Hinds (1968a) focused his study on the definition of the time of origin of neuroblasts and neurons, and glioblasts and neuroglia in both bulbs. Hinds did not pay special attention to either the morphological characteristics of the cells or their distribution into organized layers.…”

“…Among the issues in need of precision is the exact morphology of the AOB, especially when it is obtained from mice. No authors with the exception of Hinds (1968aHinds ( , 1968b have dealt with the AOB of the mouse as a whole, although some researchers have studied partial aspects of its morphology in this species (Wilson and Raisman, 1981;von Campenhausen et al, 1997;del Punta et al, 2002).…”

Increased Neurogenesis in Adult mCD24-Deficient Mice

“…Cell division persists mainly in two regions: the subventricular zone (SVZ) of the lateral ventricle and the dentate gyrus (DG) of the hippocampal formation (Hinds, 1968;Altman, 1969;Lois and Alvarez-Buylla, 1993;Luskin, 1993). In the SVZ, newborn cells migrate from the wall of the lateral ventricle into a long and well defined pathway, the rostral migratory stream (RMS), to reach the olfactory bulb (OB), where they differentiate into granular and periglomerular neurons (Doetsch and Alvarez-Buylla, 1996;Jankovski and Sotelo, 1996).…”

Spatio-temporal specification of olfactory bulb interneurons

“…Previous birth dating studies suggest that most granule and periglomerular cells in the mouse OB are generated between E18 and P5 (Hinds 1968 ), although recent studies report the initial production of OB interneurons before E18 (Wichterle et al 2001 ;Stenman et al 2003 ;Tucker et al 2006 ). During embryonic development, in contrast to the local origin of the major excitatory output (mitral and tufted) neurons, OB interneurons arise primarily from the LGE.…”