Role of serotonin, ?-aminobutyric acid, and glutamate in the behavioral thermoregulation of female tilapia during the prespawning phase

✍ Scribed by Tsai, Ching-Lin ;Wang, Li-Hsueh ;Tsai, Chia-Chiun

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 128 KB
• Volume: 293
• Category: Article
• ISSN: 0022-104X
• DOI: 10.1002/jez.10137

✦ Synopsis

Abstract

The role of hypothalamic neurotransmitter systems in behavioral thermoregulation was investigated in the prespawning female tilapia, Oreochromis mossambicus. Intrahypothalamic microinjection with serotonin (5‐HT, 3 µl of 1.0×10^−6^ M) resulted in a significant increase in the selected temperature. This effect was mimicked by the agonist of 5‐HT1A, 1B, and 2C receptors, N‐3‐trifluoromethylphenyl piperazine. Intrahypothalamic microinjection of tilapia with γ‐aminobutyric acid (GABA) resulted in a biphasic effect of the temperature selection, whereas microinjection with muscimol, an agonist of GABA~A~ receptor, had no effect on temperature selection. Both agonist and antagonist of glutamate (Glu), N‐methyl‐D‐aspartate (NMDA), and MK‐801 (1.0×10^−6^ M), a noncompetitive blocker of NMDA receptor, significantly decreased the preferred temperature. These results indicate that the hypothalamic 5‐HT, GABA, and Glu systems play a role in the temperature selection of prespawning female tilapia. J. Exp. Zool. 293:443–449, 2002. © 2002 Wiley‐Liss, Inc.