Ingestive effects of NMDA and AMPA-kainate receptor antagonists microinjections into the lateral hypothalamus of the pigeon (Columba livia).
This study examined the ingestive and behavioral effects of NMDA- and AMPA/kainate glutamatergic receptor blockade in the lateral hypothalamic area (LHy) of free-feeding pigeons (Columba livia). Injections of MK-801 (NMDA receptor antagonist; 6 nmol) or CNQX (AMPA/kainate receptor antagonist; 25.8 nmol) into the LHy of free-feeding pigeons induced significant increases in food intake and in feeding duration, as well as reductions in the latency to start feeding. Duration, latency and volume of water intake, as well as duration of sleep-like behavior, alert immobility, locomotion and preening were not changed by these treatments in the LHy. These results indicate that glutamatergic inputs to cells containing NMDA and/or AMPA receptors located in the LHy could modify both the beginning of a feeding bout (or the end of a period of satiety) and its duration (satiation). Our data also suggest that these inhibitory glutamatergic influences on feeding behavior are tonically active in the LHy.
Da Silva
Amanda A
AA
Department of Physiological Sciences, CCB, Federal University of Santa Catarina, 88040-900 Florianópolis SC, Brazil.
Campanella
Luciane Coutinho Azevedo
LC
Ramos
Mayara Caldas
MC
Faria
Moacir Serralvo
MS
Paschoalini
Marta A
MA
Marino-Neto
José
J
D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000818:Animals; D001069:Appetite Regulation / Q000187:drug effects / Q000502:physiology; D010856:Columbidae / Q000033:anatomy & histology / Q000378:metabolism*; D016291:Dizocilpine Maleate / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005247:Feeding Behavior / Q000187:drug effects / Q000502:physiology*; D018698:Glutamic Acid / Q000378:metabolism*; D007026:Hypothalamic Area, Lateral / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008845:Microinjections / Q000379:methods; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology; D009434:Neural Pathways / Q000033:anatomy & histology / Q000187:drug effects / Q000378:metabolism; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D017729:Presynaptic Terminals / Q000187:drug effects / Q000378:metabolism; D018091:Receptors, AMPA / Q000037:antagonists & inhibitors / Q000378:metabolism; D017470:Receptors, Glutamate / Q000187:drug effects / Q000378:metabolism*; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors / Q000378:metabolism; D012528:Satiety Response / Q000187:drug effects / Q000502:physiology; D013045:Species Specificity; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology
D018691:Excitatory Amino Acid Antagonists; D018091:Receptors, AMPA; D017470:Receptors, Glutamate; D016194:Receptors, N-Methyl-D-Aspartate; D018698:Glutamic Acid; D016291:Dizocilpine Maleate; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione