Central l-arginine reduced stress responses are mediated by l-ornithine in neonatal chicks

Abstract

Recently, we observed that central administration of L-arginine attenuated stress responses in neonatal chicks, but the contribution of nitric oxide (NO) to this response was minimal. The sedative and hypnotic effects of L-arginine may be due to L-arginine itself and/or its metabolites, excluding NO. To clarify the mechanism, the effect of intracerebroventricular (i.c.v.) injection of L-arginine metabolites on behavior under social separation stress was investigated. The i.c.v. injection of agmatine, a guanidino metabolite of L-arginine, had no effect during a 10 min behavioral test. In contrast, the i.c.v. injection of L-ornithine clearly attenuated the stress response in a dose-dependent manner, and induced sleep-like behavior. The L-ornithine concentration in the telencephalon and diencephalon increased following the i.c.v. injection of L-arginine. In addition, several free amino acids including L-alanine, glycine, L-proline and L-glutamic acid concentrations increased in the telencephalon. In conclusion, it appears that L-ornithine, produced by arginase from L-arginine in the brain, plays an important role in the sedative and hypnotic effects of L-arginine observed during a stress response. In addition, several other amino acids having a sedative effect might partly participate in the sedative and hypnotic effects of L-arginine.

Central Administration of Glucose Modifies Brain Amino Acid Metabolism in Neonatal Chicks

“…Thus, it is likely that these amino acids are involved in the sedative and/or hypnotic effects of glucose. On the other hand, other amino acids which have sedative effects in chicks, such as alanine (L-alanine in Kurauchi et al, 2006), asparagine (Lasparagine in Yamane et al, 2009b), ornithine (L-ornithine in Suenaga et al, 2008b), proline (L-proline in Hamasu et al, 2009), serine (L-serine in Asechi et al, 2006) and tryptophan (L-tryptophan in Yoshida et al, 2012), had no effects in the present study. The relationship among these amino acids and sedative effects of centrally injected glucose may be weak.…”

“…One of them is associated with non-essential amino acid synthesis, and some of these amino acids, such as L-glutamate, γ-amino butyric acid (GABA), glycine and so on, have crucial functions in major excitatory and inhibitory neurotransmission. In addition, some amino acids, such as L-serine, L-cysteine, glycine , L-alanine (Kurauchi et al, 2006), L-arginine (Suenaga et al, 2008a), L-ornithine (Suenaga et al, 2008b), β-alanine (Tomonaga et al, 2004) and L-proline (Hamasu et al, 2009), have sedative and/or hypnotic effects that can be induced by central injection in neonatal chicks under acute stressful conditions. On the other hand, metabotropic glutamate receptor subtype 1 (mGluR1), one of the glutamate receptors, is involved in long-term memory formation in the passive avoidance test in chicks (Baker et al, 2008).…”

Alaska Pollack Protein Decreases Brain 3-methoxy-4-hydroxyphenylglycol Levels in Fasting Chicks

“…2). L-and D-proline (Hamasu et al, 2010) and L-ornithine (Suenaga et al, 2008b) could centrally reduce stress-induced behaviors in chicks. Therefore, fasting-induced stress responses not only in the peripheral tissues but also in the brain may be reduced via proline and/or ornithine by APP.…”

“…Therefore, we chose 6 h fasting treatment and selected brain MHPG level as a good marker for this stress. We also focused on amino acids in APP, as several amino acids such as L-alanine (Kurauchi et al, 2009), β-alanine (Tomonaga et al, 2004), L-arginine (Suenaga et al, 2008a), L-aspartate (Yamane et al, 2009b), L-asparagine (Yamane et al, 2009b), L-glutamate (Yamane et al, 2009a), glycine (Shigemi et al, 2008), L-lysine (Takagi et al, 2001), L-ornithine (Suenaga et al, 2008b), L-and Dproline (Hamasu et al, 2010) and L-serine (Asechi et al, 2006(Asechi et al, , 2008Shigemi et al, 2008) function to reduce stressinduced behaviors in chicks. Therefore, changes in amino acid metabolisms were also investigated by measuring plasma free amino acids.…”

Sex-related Differences in Skeletal Muscle Amino Acid Concentrations in 20 Week Old Turkeys

“…Beside their building function in protein and polypeptides structures, FAA determine proper course of key metabolic pathways necessary for maintenance of optimal growth, reproduction and immunity in animals. Therefore FAA maximize efficiency of feed utilization, enhance protein accretion, reduce adiposity and improve health status that are important factors determining economic effectiveness in poultry production process (Wu et al, 2007;Suenaga et al, 2008;Wu, 2009;Wu et al, 2009). Abnormal amino acid metabolism disturbs organism homeostasis, impairs proper systemic growth and development, as well as may lead to death (Brodzki et al, 2005;Wu, 2009;Amorini et al, 2012).…”