Autoradiographic localization of a binding protein(s) specific for prostaglandin D2 in rat brain

The specific [3H]prostaglandin (PG) D2 binding was detected by using the slide-mounted sections of rat brain fixed by perfusion with 2% paraformaldehyde. The binding was reversible, saturable, high affinity, Na+ dependent, and highly specific for PGD2. These binding characteristics are essentially similar to those observed with the synaptic membrane of rat brain as previously reported. Using autoradiographic image analyses by computerized densitometry and color coding, we visualized the localization of [3H]PGD2 binding in rat brain. A high density of the binding sites was observed in the cerebral cortex, preoptic area, amygdala, hypothalamic nuclei (arcuate nucleus, ventromedial nucleus, and posterior hypothalamic nucleus), thalamic nuclei (reuniens nucleus and rhomboid nucleus), hippocampus, pineal body, and cerebellar cortex. The binding was not significantly observed in the striatum and also was negative in the white matter, arachnoid membranes, and vasculatures.