Dolichos biflorus agglutinin: a marker of the developing olfactory system in the NMRI-mouse strain.

The binding of horseradish peroxidase-labelled Dolichos biflorus agglutinin (HRP-DBA) to the olfactory system of NMRI-mice was investigated histochemically during the pre- and postnatal period. DBA bound with high affinity to a group of olfactory receptor neurons of both the olfactory epithelium proper and the vomeronasal organ from gestation days (g.d.) 14 and 15 onward respectively. Furthermore, there was also extensive binding to axon bundles and to the glomeruli of the main and accessory olfactory bulbs. In addition, DBA-binding was observed in goblet cells and some glands of the nasal septum. From g.d. 17 onward the number of DBA-positive neurons increased significantly and the glomeruli within the olfactory bulbs became DBA-reactive for the first time. Concomitantly, the endothelium of vessels within the olfactory epithelium's submucosa lost its DBA-affinity, though the respiratory submucosal vessels still remained DBA-positive. Possible interrelationships between DBA-affinity of blood vessel endothelium and the neighbouring olfactory neurons are discussed.