title: Exposure to sub-chronic unpredictable stress accounts for antidepressant-like effects in hamsters treated with BDNF and CNQX.
abstract: Recent evidences indicate that cerebral neurotrophic factors like vascular endothelial growth factor plus signaling pathways of the glutamatergic neuroreceptor system (L-Glu) are determinant modulators of depression-like states. In the present study, the type of interaction(s) exerted by the AMPAergic antagonist, 6-cyano-7-nitroquinoxalin-2,3-dione (CNQX) and the brain derived neurotrophic factor (BDNF) on depression-like behaviors in hamsters (Mesocricetus auratus) were investigated. Sub-chronic administration of BDNF in the hippocampal dentate gyrus (DG) of stressed hamsters was responsible for very evident (p<0.001) sucrose consumption along with notably elevated swimming bouts and reduced immobility states in the forced swim test (FST). Meanwhile, CNQX displayed evident anxiolytic actions in the elevated plus maze (EPM) as shown by marked (p<0.01) increases of movements to and from both arms. Interestingly cerebral neurodegeneration events, which are viewed during depression states, were reduced following treatment with both compounds. Contextually, marked mRNA expression levels of the BDNF receptor (tropomyosin-related kinase B; TrkB) were detected in DG and the oriens-pyramidalis of HIP (Or-Py) while a moderate (p<0.05) up-regulation was registered in the amygdalar central nucleus (CeA) and the hypothalamic ventromedial nucleus (VMH) of hamsters treated with BDNF. Similarly, this treatment caused moderate increases of the major stress protein (Hsp70) in DG and Or-Py. Conversely, while CNQX induced similar TrkB expression levels, it instead accounted for a moderate reduction of Hsp70 mRNAs in the same brain areas. Overall these results support crucial roles played by BDNF and AMPAergic neurosignaling mechanisms during distinct adaptive responses of depression- and anxiety-like states in hamsters.
authors.affiliation: Comparative Neuroanatomy Laboratory, Biology, Ecology & Earth Science Department (DiBEST), University of Calabria, Ponte Pietro Bucci 4B, 87030 Arcavacata di Rende, Cosenza, Italy. Electronic address: raffaella.alo@unical.it.
authors.forename: Raffaella
authors.initials: R
authors.lastname: Alò
authors.affiliation: Comparative Neuroanatomy Laboratory, Biology, Ecology & Earth Science Department (DiBEST), University of Calabria, Ponte Pietro Bucci 4B, 87030 Arcavacata di Rende, Cosenza, Italy.
authors.forename: Maria
authors.initials: M
authors.lastname: Mele
authors.affiliation: Comparative Neuroanatomy Laboratory, Biology, Ecology & Earth Science Department (DiBEST), University of Calabria, Ponte Pietro Bucci 4B, 87030 Arcavacata di Rende, Cosenza, Italy.
authors.forename: Gilda
authors.initials: G
authors.lastname: Fazzari
authors.affiliation: Comparative Neuroanatomy Laboratory, Biology, Ecology & Earth Science Department (DiBEST), University of Calabria, Ponte Pietro Bucci 4B, 87030 Arcavacata di Rende, Cosenza, Italy; Health Center srl, Biomedical and Nutritional Center, via Sabotino 66, 87100 Cosenza, Italy.
authors.forename: Ennio
authors.initials: E
authors.lastname: Avolio
authors.affiliation: Comparative Neuroanatomy Laboratory, Biology, Ecology & Earth Science Department (DiBEST), University of Calabria, Ponte Pietro Bucci 4B, 87030 Arcavacata di Rende, Cosenza, Italy.
authors.forename: Marcello
authors.initials: M
authors.lastname: Canonaco
mesh_terms: D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology*; D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology; D000928:Antidepressive Agents / Q000494:pharmacology*; D001007:Anxiety / Q000378:metabolism; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D019208:Brain-Derived Neurotrophic Factor / Q000494:pharmacology*; D006224:Cricetinae; D003863:Depression / Q000378:metabolism*; D018840:HSP70 Heat-Shock Proteins / Q000096:biosynthesis; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008647:Mesocricetus; D020813:Receptor, trkB / Q000096:biosynthesis; D013315:Stress, Psychological / Q000378:metabolism*
chemical_list: D014151:Anti-Anxiety Agents; D000928:Antidepressive Agents; D019208:Brain-Derived Neurotrophic Factor; D018840:HSP70 Heat-Shock Proteins; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D020813:Receptor, trkB
keywords: BDNF; CNQX; Hippocampus; Hsp70; Sub-chronic unpredictable stress