PMID- 18191115 OWN - NLM STAT- MEDLINE DCOM- 20080527 LR - 20131121 IS - 0006-8993 (Print) IS - 0006-8993 (Linking) VI - 1195 DP - 2008 Feb 21 TI - Allowing animals to bite reverses the effects of immobilization stress on hippocampal neurotrophin expression. PG - 43-9 LID - 10.1016/j.brainres.2007.12.013 [doi] AB - Acute immobilization stress alters the expression of neurotrophins, including brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3), in rat hippocampus. We found that biting may be associated with reduction of systemic stress responses. The purpose of this study was to examine whether neurotrophin expression in rat hippocampus is influenced by biting. Rats were exposed to immobilization stress for 2 h (stress group without biting) or biting for the latter half of 2-hour immobilization stress (biting group). Adrenocorticotropic hormone (ACTH) and corticosterone levels were markedly elevated in the stress group, while the increases in ACHT and corticosterone were suppressed in the biting group. Decreased BDNF mRNA and increased NT-3 mRNA expression in hippocampus were detected on real-time polymerase chain reaction (PCR) in the stress group. The decrease in BDNF mRNA under acute immobilization stress was recovered by biting. In addition, the magnitude of increase in NT-3 mRNA was decreased. No changes in expression of tyrosine receptor kinase B or C, the receptors for BDNF and NT-3, respectively, were observed in this model. These findings suggest that biting influences the alterations in neurotrophin levels induced by acute immobilization stress in rat hippocampus. FAU - Lee, Taeki AU - Lee T AD - Department of Craniofacial Growth and Development Dentistry, Kanagawa Dental College, Japan. FAU - Saruta, Juri AU - Saruta J FAU - Sasaguri, Kenichi AU - Sasaguri K FAU - Sato, Sadao AU - Sato S FAU - Tsukinoki, Keiichi AU - Tsukinoki K LA - eng PT - Journal Article PT - Research Support, Non-U.S. Gov't DEP - 20071215 PL - Netherlands TA - Brain Res JT - Brain research JID - 0045503 RN - 0 (Brain-Derived Neurotrophic Factor) RN - 0 (Neurotrophin 3) RN - 0 (RNA, Messenger) RN - 9002-60-2 (Adrenocorticotropic Hormone) RN - EC 2.7.10.1 (Receptor, trkB) RN - EC 2.7.10.1 (Receptor, trkC) RN - W980KJ009P (Corticosterone) SB - IM MH - Adaptation, Psychological/physiology MH - Adrenocorticotropic Hormone/blood MH - Analysis of Variance MH - Animals MH - Bites and Stings MH - Brain-Derived Neurotrophic Factor/genetics/*metabolism MH - Corticosterone/blood MH - Hippocampus/*metabolism MH - Male MH - Neurotrophin 3/genetics/*metabolism MH - RNA, Messenger/analysis MH - Rats MH - Rats, Sprague-Dawley MH - Receptor, trkB/genetics/metabolism MH - Receptor, trkC/genetics/metabolism MH - Restraint, Physical MH - Statistics, Nonparametric MH - Stress, Psychological/*metabolism EDAT- 2008/01/15 09:00 MHDA- 2008/05/28 09:00 CRDT- 2008/01/15 09:00 PHST- 2007/07/31 00:00 [received] PHST- 2007/11/27 00:00 [revised] PHST- 2007/12/07 00:00 [accepted] PHST- 2008/01/15 09:00 [pubmed] PHST- 2008/05/28 09:00 [medline] PHST- 2008/01/15 09:00 [entrez] AID - S0006-8993(07)02920-4 [pii] AID - 10.1016/j.brainres.2007.12.013 [doi] PST - ppublish SO - Brain Res. 2008 Feb 21;1195:43-9. doi: 10.1016/j.brainres.2007.12.013. Epub 2007 Dec 15.