Autoradiographic localization of opioid and spirodecanone receptors in the gerbil hippocampus as compared with the rat hippocampus.
Opioid ([3H]naloxone) and spirodecanone ([3H]spiperone) binding sites in the hippocampus were visualized in the Mongolian gerbil and in the rat using in vitro autoradiography. In the hippocampus, marked differences were noted in the stratum (sr.) pyramidale of the CA1 subfield where opioid and spirodecanone (assayed in the presence of mianserin and sulpiride) binding activities were very low in gerbils, but high in rats. Gerbils exhibited a high concentration of [3H]naloxone binding sites in the sr. pyramidale of the CA3 subfield, as observed in the rat. In addition, the gerbil has a very high opioid receptor density in the hilar region and in the sr. moleculare of the dentate gyrus. The cellular localization of opioid and spirodecanone receptor sites was studied in the rat hippocampus using selective neuronal damage to CA1 and CA3 neurons by means of ischemia and kainic acid treatment, respectively. The results suggest that the gerbil differs from the rat with respect to the characteristic pyramidal cells (spirodecanone binding site) and interneurons (opioid receptor) in the CA1 subfield of the hippocampus. Distinct localization of opioid and spirodecanone receptors in the gerbil provides a good model with which to investigate the electrophysiological and biochemical roles of opioid peptides and butyrophenone spirodecanone drugs.
Onodera
H
H
Department of Neurology, Tohoku University School of Medicine, Sendai, Japan.
Kogure
K
K
D000818:Animals; D001345:Autoradiography; D001665:Binding Sites; D005260:Female; D005849:Gerbillinae / Q000378:metabolism*; D008297:Male; D051381:Rats / Q000378:metabolism*; D011954:Receptors, Dopamine / Q000378:metabolism*; D011957:Receptors, Opioid / Q000378:metabolism*; D013141:Spiro Compounds / Q000378:metabolism
D011954:Receptors, Dopamine; D011957:Receptors, Opioid; D013141:Spiro Compounds; C038349:spirodecanone receptor; C014826:spirodecanone