Coexistence and gene expression of phenylethanolamine N-methyltransferase, tyrosine hydroxylase, and neuropeptide tyrosine in the rat and bovine adrenal gland: effects of reserpine.

Abstract

Expression and regulation of the catecholamine-synthesizing enzymes phenylethanolamine N-methyltransferase (PNMTase; S-adenosyl-L-methionine:phenylethanolamine N-methyltransferase, EC 2.1.1.28) and tyrosine hydroxylase [TyrOHase; tyrosine 3-monooxygenase, L-tyrosine, tetrahydropteridine:oxygen oxidoreductase (3-hydroxylating), EC 1.14.16.2] and the coexisting neuropeptide tyrosine (NPY) were studied in rat and bovine adrenal medulla. By using both immunohistochemistry and in situ hybridization, PNMTase-and NPY-positive cells exhibited a close overlap in bovine medulla and were preferentially localized in the outer two-thirds of the medulla. Although TyrOHase and its mRNA were observed in virtually all medullary gland cells, TyrOHase mRNA levels were much higher in the PNMTase-and NPYpositive cells. After administration of the catecholaminedepleting drug reserpine to rats, a brief increase, followed by a dramatic decrease, in the level of PNMTase mRNA was observed in the adrenal medulla. In contrast, mRNA for both TyrOHase and NPY only exhibited an increase, whereby the TyrOHase mRNA peak preceded that of NPY mRNA. Different regulatory mechanisms may thus operate for these three compounds coexisting in the adrenal medulla.

Protein kinase A and protein kinase C signaling pathway interaction in phenylethanolamine N‐methyltransferase gene regulation

“…In the adrenal gland, neural regulation of the genes encoding the catecholamine biosynthetic enzymes, TH, DBH and PNMT, is mediated by neurotransmitters released from the splanchnic nerve (Schalling et al 1988;Wessel and Joh 1992;, which bind to receptors to activate intracellular signaling pathways and transcription factors. Stimulation of the splanchnic nerve stimulates a number of second messenger systems within the adrenal medullary cells, including that of cAMP dependent-protein kinase A and protein kinase C (Malhotra et al 1989;FischerColbrie et al 1992), and both of these pathways appear important for catecholamine enzyme regulation.…”

“…In the adrenal gland, neural regulation of PNMT is mediated via the splanchnic nerve (Schalling et al 1988;Wessel and Joh 1992;Wong et al 1993;, that synthesizes and secretes a number of neurotransmitters. One of these transmitters, the classical neurotransmitter acetylcholine, has been extensively studied in the regulation of the catecholamine biosynthetic enzymes, including PNMT.…”

Hypermethylation of the WT1 and calcitonin gene promoter regions at chromosome 11p in human colorectal cancer

“…Tissue samples were cut into 1 0-,um sections with a cryostat (Leica CM3000, Germany) at -20°C, collected onto precleaned slides (Menzel-Glaser, Germany) and processed for in situ hybridization using the method as described in Schalling et al (1988). The oligonucleotide probe (5'-CGGAGCCCA'TT'GCTGAGGCTCA-GACCCGGACGCCCCGCGGCTCCTCCGGCCCTGG-3') used was 3' end labelled using terminal deoxynucleotidyltransferase (New England Nuclear, Boston, MA, USA) and 35S-labelled deoxyadenosine triphosphate (New England Nuclear).…”

Prolonged Expression of hsp70 mRNA following Transient Focal Cerebral Ischemia in Transgenic Mice Overexpressing CuZn-Superoxide Dismutase

“…The brains were frozen in mounting medium and stored at -70°C. Brain sections (20 f-lm) were cut on a cryostat at -20°C, collected onto precleaned slides, and processed for in situ hybridization using the method of Schalling et al (1988) with minor modifications. The slides were hy bridized at 37°C for 18 h with 1 x 106 cpm of a 35S-labeled synthetic oligonucleotide (30-mer) probe that corre sponds to highly conserved amino acids 122-129 near the 5'-end of the human hsp70 coding sequence (Hunt and Morimoto, 1985).…”