کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9149850 1166440 2005 6 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Tyrosine prevents effects of hyperthermia on behavior and increases norepinephrine
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی فیزیولوژی
پیش نمایش صفحه اول مقاله
Tyrosine prevents effects of hyperthermia on behavior and increases norepinephrine
چکیده انگلیسی
Tyrosine (TYR) is the precursor of the catecholamine (CA) neurotransmitters, dopamine (DA) and norepinephrine (NE). Catecholamines, especially NE, participate in the response of the brain to acute stress. When animals are acutely stressed, NE neurons become more active and tyrosine availability may be rate-limiting. Tyrosine administration, before exposure to physical and/or environmental stressors including cold, reduces the adverse behavioral, physiological and neurochemical consequences of the exposure. In this study, the effects of tyrosine (400 mg/kg) were examined on rats exposed to heat stress, for which its effects have not been examined. Coping behavior and memory were assessed using the Porsolt swim test and the Morris water maze. Release of hippocampal NE and DA was assessed with in vivo microdialysis. In vehicle-treated animals, heat impaired coping and memory, and increased release of NE, but not DA. In heated animals receiving tyrosine, coping was not impaired and NE release was sustained, thus demonstrating tyrosine protects against the adverse effects of heat, and suggesting these effects result from increased central NE release. This study indicates the effects of tyrosine generalize across dissimilar stressors and that tyrosine administration may mitigate the adverse behavioral effects of heat and other stressors on humans. In addition, it demonstrates that moderate heat stress impairs coping behavior, as well as working and reference memory.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Physiology & Behavior - Volume 84, Issue 1, 31 January 2005, Pages 33-38
نویسندگان
, , , ,