DETECTION OF NERVE GROWTH-FACTOR MESSENGER-RNA IN RODENT SALIVARY-GLANDS WITH DIGOXIGENIN-LABELED AND P-33 LABELED OLIGONUCLEOTIDES - EFFECTS OF CASTRATION AND SYMPATHECTOMY

Nerve growth factor (NGF) is a protein highly expressed in the male mo use submandibular gland. We have applied a non-radioactive in situ hyb ridization method using digoxigenin-labeled NGF oligonucleotides, and have found the highest amounts of NGF mRNA in the secretory striated d ucts of the male mouse submandibular gland. Scattered strongly positiv e cells were found in male mouse sublingual glands. Weakly labeled cel ls were seen in female mouse and in male rat submandibular gland stria ted duct cells. Using P-33 as an alternative to P-32 and S-35, we demo nstrated a 1.3 KB NGF mRNA in salivary glands of male mice by Northern blot hybridization. Using P-33 we detected NGF mRNA in male mouse sub mandibular glands by in situ hybridization but with a signal that, com pared with the nonradioactive method, had a very low resolution. Castr ation of male mice almost abolished both the 1.3 KB NGF mRNA seen with Northern blots and the NGF mRNA labeling in submandibular glands 4 we eks after the operation, whereas levels were increased 6 hr and 2 days after sympathectomy. We conclude that hybridization with digoxigenin- labeled NGF oligonucleotides is a good tool to study the expression an d regulation of NGF mRNA in male mouse submandibular glands.