Premium
Convergence of olfactory and vomeronasal projections in the rat basal telencephalon
Author(s) -
ProSistiaga Palma,
MohedanoMoriano Alicia,
UbedaBañon Isabel,
del mar ArroyoJimenez Maria,
Marcos Pilar,
ArtachoPérula Emilio,
Crespo Carlos,
Insausti Ricardo,
MartinezMarcos Alino
Publication year - 2007
Publication title -
journal of comparative neurology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.855
H-Index - 209
eISSN - 1096-9861
pISSN - 0021-9967
DOI - 10.1002/cne.21455
Subject(s) - vomeronasal organ , stria terminalis , cerebrum , biology , olfactory system , neuroscience , amygdala , olfactory tubercle , anatomy , extended amygdala , olfactory bulb , central nervous system
Olfactory and vomeronasal projections have been traditionally viewed as terminating in contiguous non‐overlapping areas of the basal telencephalon. Original reports, however, described areas such as the anterior medial amygdala where both chemosensory afferents appeared to overlap. We addressed this issue by injecting dextran amines in the main or accessory olfactory bulbs of rats and the results were analyzed with light and electron microscopes. Simultaneous injections of different fluorescent dextran amines in the main and accessory olfactory bulbs were performed and the results were analyzed using confocal microscopy. Similar experiments with dextran amines in the olfactory bulbs plus FluoroGold in the bed nucleus of the stria terminalis indicate that neurons projecting through the stria terminalis could be integrating olfactory and vomeronasal inputs. Retrograde tracing experiments using FluoroGold or dextran amines confirm that areas of the rostral basal telencephalon receive inputs from both the main and accessory olfactory bulbs. While both inputs clearly converge in areas classically considered olfactory‐recipient (nucleus of the lateral olfactory tract, anterior cortical amygdaloid nucleus, and cortex–amygdala transition zone) or vomeronasal‐recipient (ventral anterior amygdala, bed nucleus of the accessory olfactory tract, and anteroventral medial amygdaloid nucleus), segregation is virtually complete at posterior levels such as the posteromedial and posterolateral cortical amygdalae. This provides evidence that areas so far considered receiving a single chemosensory modality are likely sites for convergent direct olfactory and vomeronasal inputs. Therefore, areas of the basal telencephalon should be reclassified as olfactory, vomeronasal, or mixed chemosensory structures, which could facilitate understanding of olfactory–vomeronasal interactions in functional studies. J. Comp. Neurol. 504:346–362, 2007. © 2007 Wiley‐Liss, Inc.