title: Immunocytological localization of dopamine in the guinea pig retina.
abstract: We examined dopaminergic neurons in the guinea pig retina; antisera against tyrosine hydroxylase (TH), dopamine beta-hydroxylase (DBH), phenylethanolamine N-methyltransferase (PNMT) and an antiserum against gamma-aminobutyric acid (GABA) were used. In the present study, two types of amacrine cells were labeled with an anti-TH antiserum. However, no DBH and PNMT immunoreactivities were seen. The type 1 cell had a larger-sized soma located in the inner nuclear layer with processes ramifying mainly in stratum 1 of the inner plexiform layer (IPL). The type 2 cell had a smaller-sized soma and processes branching in stratum 3 of the IPL. The mean densities were 56.4 +/- 11.5/mm2 for the type 1 cell and 166.6 +/- 30.3/mm2 for the type 2 cell. Double immunocytochemistry using an antiserum against GABA revealed that while none of the type 1 cells showed GABA immunoreactivity, all of the type 2 cells displayed GABA immunoreactivity. Our results suggest that, in the guinea pig retina, the type 1 amacrine cells are pure dopaminergic and the type 2 cells are dopaminergic elements that use GABA as their second transmitter.
authors.affiliation: Department of Anatomy, College of Medicine, Catholic University of Korea, Seoul.
authors.forename: S J
authors.initials: SJ
authors.lastname: Oh
authors.forename: I B
authors.initials: IB
authors.lastname: Kim
authors.forename: E J
authors.initials: EJ
authors.lastname: Lee
authors.forename: K Y
authors.initials: KY
authors.lastname: Kim
authors.forename: H I
authors.initials: HI
authors.lastname: Kim
authors.forename: M H
authors.initials: MH
authors.lastname: Chun
mesh_terms: D000367:Age Factors; D000818:Animals; D004298:Dopamine / Q000032:analysis*; D006168:Guinea Pigs; D007124:Immunoenzyme Techniques; D009475:Neurons, Afferent / Q000737:chemistry / Q000201:enzymology; D012160:Retina / Q000737:chemistry* / Q000166:cytology / Q000201:enzymology; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis; D005680:gamma-Aminobutyric Acid / Q000032:analysis
chemical_list: D005680:gamma-Aminobutyric Acid; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine