Region-specific upregulation of parvalbumin-, but not calretinin-positive cells in the ventral hippocampus during adolescence
Article first published online: 2 SEP 2013
Copyright © 2013 Wiley Periodicals, Inc.
Volume 23, Issue 12, pages 1331–1336, December 2013
How to Cite
Caballero, A., Diah, K. C. and Tseng, K. Y. (2013), Region-specific upregulation of parvalbumin-, but not calretinin-positive cells in the ventral hippocampus during adolescence. Hippocampus, 23: 1331–1336. doi: 10.1002/hipo.22172
- Issue published online: 20 NOV 2013
- Article first published online: 2 SEP 2013
- Accepted manuscript online: 26 JUL 2013 05:38PM EST
- Manuscript Accepted: 21 JUL 2013
- Manuscript Revised: 2 MAY 2013
- Manuscript Received: 20 FEB 2013
- NIMH R01-MH086507 (KYT), The Brain Research Foundation (KYT), and Rosalind Franklin University (KYT)
- ventral hippocampus;
Animal studies have highlighted the role of the ventral hippocampus-prefrontal cortex pathway in the acquisition of mature cortical function through refinement of GABAergic circuits during adolescence. Inhibitory GABAergic responses are mediated by highly specialized interneurons, which have distinct functional properties and are characterized by the expression of calcium binding proteins. Among these, we recently found that parvalbumin (PV)- and calretinin (CR)-positive interneurons in the prefrontal cortex follow opposite developmental trajectories during the periadolescent transition period. In the present study, we asked whether interneurons expressing PV and CR in the ventral hippocampus follow similar periadolescent trajectories as seen in the prefrontal cortex. By measuring the relative abundance of these interneurons in three age groups (postnatal days (PD) 25–40, 45–55, and 60–85), we found that regions within the dorso-ventral axis of the ventral hippocampus undergo distinct developmental trajectories in PV expression during the periadolescent transition. Specifically, the ventral subiculum displayed a dramatic increase in PV-positive interneurons from PD25–40 to PD45–55 with an increasing rostro-caudal gradient, whereas negligible changes were found in the dorsal and middle regions. In contrast, the number of CR-positive interneurons in the ventral hippocampus remained unchanged across the three age groups studied. Together, these results describe for the first time that GABAergic circuits in the ventral hippocampus undergo protracted development during adolescence, in particular the PV-positive cell population circumscribed to the ventral region of the ventral hippocampus. © 2013 Wiley Periodicals, Inc.