title: Role of serotonin, gamma-aminobutyric acid, and glutamate in the behavioral thermoregulation of female tilapia during the prespawning phase.
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 microliters of 1.0 x 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 gamma-aminobutyric acid (GABA) resulted in a biphasic effect of the temperature selection, whereas microinjection with muscimol, an agonist of GABAA receptor, had no effect on temperature selection. Both agonist and antagonist of glutamate (Glu), N-methyl-D-aspartate (NMDA), and MK-801 (1.0 x 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.
authors.affiliation: Department of Marine Resources, National Sun Yat-sen University, Kaohsiung, Taiwan 80424. cltsai@mail.nsysu.edu.tw
authors.forename: Ching-Lin
authors.initials: CL
authors.lastname: Tsai
authors.forename: Li-Hsueh
authors.initials: LH
authors.lastname: Wang
authors.forename: Chia-Chiun
authors.initials: CC
authors.lastname: Tsai
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D001833:Body Temperature Regulation / Q000187:drug effects*; D016291:Dizocilpine Maleate / Q000494:pharmacology; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D005260:Female; D018755:GABA Agonists / Q000494:pharmacology; D018698:Glutamic Acid / Q000378:metabolism / Q000494:pharmacology*; D007031:Hypothalamus / Q000378:metabolism; D009118:Muscimol / Q000494:pharmacology; D016202:N-Methylaspartate / Q000494:pharmacology; D012098:Reproduction / Q000187:drug effects*; D012701:Serotonin / Q000378:metabolism / Q000494:pharmacology*; D017210:Tilapia / Q000502:physiology*; D013997:Time Factors; D005680:gamma-Aminobutyric Acid / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D018690:Excitatory Amino Acid Agonists; D018755:GABA Agonists; D009118:Muscimol; D012701:Serotonin; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid; D016202:N-Methylaspartate; D016291:Dizocilpine Maleate