caa a22 4500 606202951 CHVBK 20210128100955.0 cr unu---uuuuu 210128e20150901xx s 000 0 eng 10.1007/s00429-014-0831-8 doi (NATIONALLICENCE)springer-10.1007/s00429-014-0831-8 Identification of dorsal-ventral hippocampal differentiation in neonatal rats [Elektronische Daten] [Kally O'Reilly, Arnar Flatberg, Sobia Islam, Lene Olsen, Ingvild Kruge, Menno Witter] The adult hippocampal formation (HF) is functionally, connectionally, and transcriptionally differentiated along the dorsal-ventral axis. At birth, the hippocampus appears shortened along its dorsal-ventral axis. We therefore questioned at what postnatal age the differentiated dorsal-ventral hippocampus is present. We first established that the ventral tissue in the short postnatal hippocampus remains ventral in the adult-like hippocampus. Second, using anatomical tracing techniques we report that, within the first postnatal week, the main input from the entorhinal cortex (EC) to HF is topographically organized. The terminal distribution of this input along the dorsal-ventral axis of HF was related to a dorsolateral-to-ventromedial axis of origin in EC, thus reflecting adult topography. Finally, we examined gene expression along the dorsal-ventral axis in the developing hippocampus. We found that several genes that were differentially enriched in the adult dorsal and ventral hippocampus were similarly enriched in the dorsal and ventral hippocampal poles at birth. The differentially expressed genes relate to different molecular pathways and biomarkers of disease. Taken together, these data lead us to conclude that the entire dorsal-ventral axis of HF is present at birth showing adult-like functional differentiation. Moreover, our findings indicate that the neonatal ventral hippocampus is enriched with biomarkers associated with mental illnesses. These include schizophrenia, affective and anxiety disorders, disorders previously deemed as ventral hippocampal associated disorders, as well as alcoholism. Our results thus suggest an early developmental susceptibility of the ventral HF to mental illness. Springer-Verlag Berlin Heidelberg, 2014 Development nationallicence Dorsal-ventral hippocampus nationallicence Hippocampal transcription nationallicence Entorhinal-hippocampal connectivity nationallicence O'Reilly Kally Kavli Institute for Systems Neuroscience, Centre for Neural Computation, Medical Technical Research Centre, Norwegian University of Science and Technology, Postboks 8905, 7491, Trondheim, Norway aut Flatberg Arnar Institute for Cancer Research and Molecular Medicine, NTNU, 7491, Trondheim, Norway aut Islam Sobia Kavli Institute for Systems Neuroscience, Centre for Neural Computation, Medical Technical Research Centre, Norwegian University of Science and Technology, Postboks 8905, 7491, Trondheim, Norway aut Olsen Lene Institute for Cancer Research and Molecular Medicine, NTNU, 7491, Trondheim, Norway aut Kruge Ingvild Kavli Institute for Systems Neuroscience, Centre for Neural Computation, Medical Technical Research Centre, Norwegian University of Science and Technology, Postboks 8905, 7491, Trondheim, Norway aut Witter Menno Kavli Institute for Systems Neuroscience, Centre for Neural Computation, Medical Technical Research Centre, Norwegian University of Science and Technology, Postboks 8905, 7491, Trondheim, Norway aut Brain Structure and Function Springer Berlin Heidelberg 220/5(2015-09-01), 2873-2893 1863-2653 220:5<2873 2015 220 429 https://doi.org/10.1007/s00429-014-0831-8 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00429-014-0831-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- O'Reilly Kally Kavli Institute for Systems Neuroscience, Centre for Neural Computation, Medical Technical Research Centre, Norwegian University of Science and Technology, Postboks 8905, 7491, Trondheim, Norway aut NATIONALLICENCE 700 1- Flatberg Arnar Institute for Cancer Research and Molecular Medicine, NTNU, 7491, Trondheim, Norway aut NATIONALLICENCE 700 1- Islam Sobia Kavli Institute for Systems Neuroscience, Centre for Neural Computation, Medical Technical Research Centre, Norwegian University of Science and Technology, Postboks 8905, 7491, Trondheim, Norway aut NATIONALLICENCE 700 1- Olsen Lene Institute for Cancer Research and Molecular Medicine, NTNU, 7491, Trondheim, Norway aut NATIONALLICENCE 700 1- Kruge Ingvild Kavli Institute for Systems Neuroscience, Centre for Neural Computation, Medical Technical Research Centre, Norwegian University of Science and Technology, Postboks 8905, 7491, Trondheim, Norway aut NATIONALLICENCE 700 1- Witter Menno Kavli Institute for Systems Neuroscience, Centre for Neural Computation, Medical Technical Research Centre, Norwegian University of Science and Technology, Postboks 8905, 7491, Trondheim, Norway aut NATIONALLICENCE 773 0- Brain Structure and Function Springer Berlin Heidelberg 220/5(2015-09-01), 2873-2893 1863-2653 220:5<2873 2015 220 429