title: Mammal retinal distribution of ENKergic amacrine cells and their neurochemical features: evidence from the PPE-GFP transgenic mice.
abstract: The neuroactive peptide enkephalin (ENK) has been postulated to play important roles in modulating visual information. The retinal presence of ENKergic cells has been revealed with conventional morphological protocols targeting ENK molecule especially in avian, however, the detailed distribution of ENKergic cells and their specific neurochemical features in the mammal retina remain unclear because of the difficulties in visualizing ENKergic cells efficiently and reliably. To address this question, we took advantage of the preproenkephalin-green fluorescent protein (PPE-GFP) transgenic mice previously generated and identified in our group, and identified the neurochemical characteristics of retinal ENKergic cells. The majority of ENKergic cells occupied the proximal inner nuclear layer with a few displaced in the ganglion cell layer. Further double labeling revealed that most of these ENKergic amacrine cells used inhibitory glycine or gamma-aminobutyric acid as the primary neurotransmitter. However, some of them also utilized excitatory glutamate as the primary neurotransmitter. The present findings suggest that the retinal ENKergic cells fall into a subpopulation of amacrine cells and show predominantly inhibitory as well as less dominantly excitatory neurochemical features. Our findings offered comprehensive morphological evidence for the function of ENKergic amacrine cells of mammal species.
authors.affiliation: Department of Anatomy, Histology and Embryology & K.K. Leung Brain Research Centre, Preclinical School of Medicine, Fourth Military Medical University, Xi'an 710032, PR China.
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.forename: Yan
authors.initials: Y
authors.lastname: Lin
authors.forename: Jing
authors.initials: J
authors.lastname: Huang
authors.forename: Wen
authors.initials: W
authors.lastname: Wang
authors.forename: Yan-Yan
authors.initials: YY
authors.lastname: Wei
authors.forename: Yun-Qing
authors.initials: YQ
authors.lastname: Li
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kaneko
authors.forename: Sheng-Xi
authors.initials: SX
authors.lastname: Wu
mesh_terms: D025042:Amacrine Cells / Q000145:classification / Q000166:cytology* / Q000378:metabolism*; D000818:Animals; D002478:Cells, Cultured; D004745:Enkephalins / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009415:Nerve Net / Q000166:cytology / Q000378:metabolism; D009433:Neural Inhibition / Q000502:physiology*; D014018:Tissue Distribution; D014796:Visual Perception / Q000502:physiology*
chemical_list: D004745:Enkephalins
keywords: Amacrine cells; Enkephalin; Retina; Transgenic mice