title: BDNF and TrkB co-localize in CA1 neurons resistant to transient forebrain ischemia in the adult gerbil.
abstract: Delayed cell death of projection cells in the CA1 area of the hippocampus is produced in the adult gerbil following 5 minutes (min) of transient forebrain ischemia. Parvalbumin-immunoreactive local-circuit neurons are resistant to the ischemic insult. Brain-Derived Neurotrophic Factor (BDNF) immunoreactivity is localized in all neurons of the CA1 area in control gerbils. However, TrkB immunoreactivity is observed in a minority of BDNF-immunoreactive neurons in the CA1 area. The number of BDNF-immunoreactive cells in CA1 is dramatically reduced in ischemic gerbils as early as 24 h after ischemia, but the number of TrkB-immunoreactive cells in the CA1 area is maintained following ischemia. Moreover, about 90% of BDNF-immunoreactive cells and about 85% of TrkB-immunoreactive cells in ischemic gerbils co-localize the calcium-binding protein parvalbumin. Finally, BDNF and TrkB are coexpressed in about 95% of CA1 neurons surviving the ischemic insult. These results indicate that a subpopulation of CA1 hippocampal neurons coexpressing TrkB, parvalbumin and BDNF is resistant to transient forebrain ischemia in the gerbil. These results also suggest that a subpopulation of CA1 hippocampal neurons in the gerbil hippocampus is endowed with a putative BDNF/TrkB autocrine regulatory loop that may be involved in both cell survival and synaptic remodeling of the damaged gerbil hippocampus following transient forebrain ischemia.
authors.affiliation: Unitat de Neuropatologia, Hospital Princeps d'Espanya, Spain.
authors.forename: I
authors.initials: I
authors.lastname: Ferrer
authors.forename: J
authors.initials: J
authors.lastname: Ballabriga
authors.forename: E
authors.initials: E
authors.lastname: Martí
authors.forename: E
authors.initials: E
authors.lastname: Pozas
authors.forename: A M
authors.initials: AM
authors.lastname: Planas
authors.forename: J
authors.initials: J
authors.lastname: Blasi
mesh_terms: D000818:Animals; D002545:Brain Ischemia / Q000473:pathology*; D019208:Brain-Derived Neurotrophic Factor / Q000378:metabolism*; D002470:Cell Survival; D005849:Gerbillinae; D006624:Hippocampus / Q000378:metabolism*; D007124:Immunoenzyme Techniques; D008297:Male; D009474:Neurons / Q000378:metabolism*; D016548:Prosencephalon / Q000473:pathology*; D020801:Receptor, Ciliary Neurotrophic Factor; D017475:Receptors, Nerve Growth Factor / Q000378:metabolism*; D013997:Time Factors
chemical_list: D019208:Brain-Derived Neurotrophic Factor; D020801:Receptor, Ciliary Neurotrophic Factor; D017475:Receptors, Nerve Growth Factor