title: Absence of adrenaline neurons in the guinea pig brain: a combined immunohistochemical and high-performance liquid chromatography study.
abstract: The distributions of catecholamine (CA) neurons in the medulla oblongata of the guinea pig and rat were compared using immunohistochemistry with rabbit antisera against the CA synthesizing enzymes, tyrosine hydroxylase (TH), dopamine-beta-hydroxylase (D beta H) and phenylethanolamine-N-methyltransferase (PNMT). TH and D beta H distributions were similar in the two species. In contrast, the central nervous systems of both normal and colchicine-treated guinea pigs failed to demonstrate immunoreactivity for PNMT, the synthetic enzyme for adrenaline. The concentrations of biogenic amines in the hypothalamus and medulla were determined in guinea pig and rat tissues by high-performance liquid chromatography with electrochemical detection. No adrenaline was detected in the guinea pig brain. Thus it appears that guinea pigs lack central neurons capable of synthesizing adrenaline.
authors.forename: P
authors.initials: P
authors.lastname: Cumming
authors.forename: M
authors.initials: M
authors.lastname: Von Krosigk
authors.forename: P B
authors.initials: PB
authors.lastname: Reiner
authors.forename: E G
authors.initials: EG
authors.lastname: McGeer
authors.forename: S R
authors.initials: SR
authors.lastname: Vincent
mesh_terms: D000320:Adrenergic Fibers; D000818:Animals; D001679:Biogenic Amines / Q000032:analysis; D001921:Brain / Q000166:cytology* / Q000201:enzymology; D001923:Brain Chemistry; D002851:Chromatography, High Pressure Liquid; D004299:Dopamine beta-Hydroxylase / Q000378:metabolism; D006168:Guinea Pigs; D007124:Immunoenzyme Techniques; D008297:Male; D010625:Phenylethanolamine N-Methyltransferase / Q000378:metabolism; D051381:Rats; D014446:Tyrosine 3-Monooxygenase / Q000378:metabolism
chemical_list: D001679:Biogenic Amines; D014446:Tyrosine 3-Monooxygenase; D004299:Dopamine beta-Hydroxylase; D010625:Phenylethanolamine N-Methyltransferase