Autoradiographic and in situ hybridization localization of corticotropin-releasing factor 1 and 2 receptors in nonhuman primate brain

Two different corticotropin-releasing factor (CRF) receptors, CRF1 and CRF2 , have been identified in rat and human brain. Although the two receptor su btypes show a markedly different distribution in the rat brain, their distr ibution in the primate brain has not been described previously. In this stu dy, the neuroanatomic distribution of CRF1 and CRF2 receptor binding sites in rhesus monkey (Macaca mulatta) was assessed by using iodine 125 ([I-125) -Tyr(0)] -sauvagine with or without the selective CRF1 receptor antagonist CP-154,526-1. Radiolabeled human cRNA probes were used to map the distribut ion of the two receptor mRNAs with in situ hybridization. Both CRF1 and CRF 2 receptors were found in the pituitary and throughout the neocortex (espec ially, in prefrontal, cingulate, striate, and insular cortices), amygdala, and hippocampal formation of the monkey brain. This is in contrast to the d istribution of these receptors reported in the rat brain, in which generall y only the CRF1 receptor is found in the pituitary and neocortex. These res ults suggest that, in primates, both CRF1 and CRF2 receptors may be involve d in mediating the effects of CRF on cognition, behavior, and pituitary-adr enal function. The presence of CRF1 (but not CRF2) receptors within the loc us coeruleus, cerebellar cortex, nucleus of the solitary tract, thalamus, a nd striatum and of CRF2 (but not CRF1) receptors in the choroid plexus, cer tain hypothalamic nuclei, the nucleus prepositus, and the nucleus of the st ria terminalis suggests that each receptor subtype also may have distinct f unctional roles within the primate central nervous system. (C) 1999 Wiley-L iss, Inc.