New neurons are continuously being added to the olfactory bulb (OB) of adult rodents that are generated in the
subventricular zone (SVZ), distant by a few millimeters. Neuronal precursors have to overcome this long distance without
the radial-glial migratory scaffold, in contrast to migration mode during embryonic development. The previous model
explains migration of precursors from the SVZ through the rostral migratory stream (RMS) to the OB as a movement of
neuroblasts along each other, ensheathed by astroglial tubes. Recent results indicate that blood vessels are suitable
candidates for neuronal migration guidance in the RMS. These novel findings have changed the former concept
accounting for neuronal precursor migration. The aim of our study was to map a pattern of vascularization in the RMS of
adult rats and to investigate mutual relations among blood vessels, neuroblasts and astrocytes in this area. Detailed
morphological analysis revealed that blood vessels in the RMS are organized in a specific manner. In most of the RMS
extent, blood vessels run parallel to the outline of the migratory pathway. Interestingly, the caudal part of the RMS has a
unique vasculature organization in which blood vessels create a spiral-like configuration. Chains of neuroblasts enveloped
by astrocytes largely align along blood vessels. The exception is the caudal part of the RMS where neuroblasts do not
follow non – parallel blood vessels. Our morphological findings suggest that blood vessels and astrocytes may
cooperatively form physical substrate - scaffold for the neuroblasts migration in the RMS of adult rats.
Keywords: Adult rats, astrocytes, blood vessels, neuroblasts migration, neurogenesis, rostral migratory stream.
Rights & PermissionsPrintExport