Intracranial self-stimulation enhances neurogenesis in hippocampus of adult mice and rats.
Running is known to promote neurogenesis. Besides being exercise, it results in a reward, and both of these factors might contribute to running-induced neurogenesis. However, little attention has been paid to how reward and exercise relate to neurogenesis. The present study is an attempt to determine whether a reward, in the form of intracranial self-stimulation (ICSS), influences neurogenesis in the hippocampus of adult rodents. We used bromodeoxyuridine labeling to quantify newly generated cells in mice and rats that experienced ICSS for 1 h per day for 3 days. ICSS increased the number of 5-bromodeoxyuridine (Brdu)-labeled cells in the hippocampal dentate gyrus (DG) of both species. The effect, when examined at 1 day, 1 week, and 4 weeks post-ICSS, was predominantly present in the side ipsilateral to the stimulation, although it was distributed to the contralateral side. We also found in rats that, 4 weeks after Brdu injection, surviving newborn cells in the hippocampal DG of the ICSS animals co-localized with a mature neuron marker, neuronal nuclei (NeuN), and these surviving cells in rats were double-labeled with Fos, a marker of neuronal activation, after the rats had been trained to perform a spatial task. The results demonstrate that ICSS can increase newborn neurons in the hippocampal DG that endure into maturity.
Takahashi
T
T
Department of Psychology, Hamamatsu University School of Medicine, 1-20-1 Handayama, Higashi-ku, Hamamatsu 431-3192, Shizuoka 431-3192, Japan.
Zhu
Y
Y
Hata
T
T
Shimizu-Okabe
C
C
Suzuki
K
K
Nakahara
D
D
D000818:Animals; D001522:Behavior, Animal; D001973:Bromodeoxyuridine / Q000378:metabolism; D002452:Cell Count / Q000379:methods; D049109:Cell Proliferation; D003216:Conditioning, Operant / Q000502:physiology*; D004558:Electric Stimulation / Q000379:methods*; D007839:Functional Laterality; D018756:GABA Antagonists / Q000494:pharmacology; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006624:Hippocampus / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D008297:Male; D018782:Maze Learning / Q000502:physiology; D051379:Mice; D008808:Mice, Inbred CBA; D055495:Neurogenesis / Q000187:drug effects / Q000502:physiology*; D010433:Pentylenetetrazole / Q000494:pharmacology; D010751:Phosphopyruvate Hydratase / Q000378:metabolism; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D012646:Self Administration / Q000379:methods; D013997:Time Factors
D018756:GABA Antagonists; D005904:Glial Fibrillary Acidic Protein; D016760:Proto-Oncogene Proteins c-fos; D010751:Phosphopyruvate Hydratase; D001973:Bromodeoxyuridine; D010433:Pentylenetetrazole