Expression of mammalian RF-amide peptides neuropeptide FF (NPFF), prolactin-releasing peptide (PrRP) and the PrRP receptor in the peripheral tissues of the rat.

The mRNA expression of neuropeptide FF (NPFF), prolactin-releasing peptide (PrRP) and the UHR-1/GPR10 receptor were examined using in situ hybridization in rat peripheral tissues. In the hypophysis, modest expression of PrRP and receptor mRNA were seen in the anterior lobe. The trigeminal ganglion was devoid of expression signals. PrRP and UHR-1/GPR10 receptor mRNA:s were found in the adrenal medulla and PrRP mRNA was found in the pancreas. NPFF mRNA was detected in the spleen. In the testis and epididymis, PrRP and UHR-1/GPR10 receptor mRNA:s were detected. The results suggest a limited expression of mammalian RF-amide peptides in the peripheral organs.