Estudo neurobiológico de componentes do sono em codornas (Coturnix japonica) (Temminck Schlegel, 1849) (Aves: Galliformes)

Abstract

This work gives continuity to an incidental discovery from the Laboratory of Animal Plhysiology of UFRRJ, in the Department of Physiologic Science in which quails were treated periphericaly by serotonin, in a study of feeding behavior became sleep. From this evidence, the idea of which serotonin permeates the blood-brain barrier (BBB) of the birds, differently to mammals, incited new investigations about neuropharmacology and regarding this issue. Firstly, a study of antagonists e agonists of serotonergic receptors was held, confirming the permeability of the barrier of (BBB) of quails to serotonin and your participation in the central mechanisms involved in the regulation of the similar sleep-like behaviors. This research resulted in a publication of a first in the Brazilian Journal of Biology, in 2007, entitled "Behavioral and neuropharmacological evidence that serotonin crosses the bloodbrain barrier in Cortunix japonica (Galliformes: Aves). Taking into consideration that the serotonin is the precursor of melatonin and this last one is involved in the control of the circadian rhythm, we continued with the investigation about the plasma leveis of melatonin, by means of application of the serotonin precursor, L-5-hydroxy-tryptophan. This study resulted in the publication of a second article in the Brazilian Journal of Biology, in 2007, "Nocturnal plasma levels of melatonin in quails (Cortunix japonica) injected with L-5-hydroxy-tryptophan". Once the behaviors related to sleep involves a series of central inhibition and the y-aminobutyric acid (GABA) is the biggest central inhibitory neurotransmitter of the central nervous system, we continued exploring behavioral and neuropharmacologically broaching the one type of gabaergic receptor, aiming the sleep of quails, the complex receptor GABAA. This work resulted in the third and last publication of this doctorate work, "Study of GABAA receptors on the sleep-like behavior in Cortunix japonica (Temminck Schlegel, 1849) (Galliformes: Aves)", in the Journal of Comparative Physiology A, in 2008. Toe aim of this thesis was not to draw a parallel between birds and mammals. However, many evidences were inevitable. Certainly, this research contributed to increase the scientific knowledge of the analysed elements. There is still too much to investigate concerning sleep, not only in birds, but also in mammals.