Distribution and daily fluctuation of the available glucocorticoid binding sites in different areas of the quail brain.

The distribution and daily fluctuation of available glucocorticoid binding sites was studied in the brain of the quail Coturnix coturnix japonica, under physiological circumstances. A high level of triamcinolone acetonide binding was observed in some limbic structures (hippocampus and archistriatum), in the nucleus medialis and lateralis posterioris hypothalami and in the cerebellar cortex. The daily fluctuation of the available glucocorticoid binding sites in the preoptic area, hippocampus, archistriatum and cerebellar cortex can be described with a curve antiphased to the daily rhythm of plasma corticosterone concentration and seems to be synchronized by the plasma corticosterone level.