On Bipolar Neurons is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
ON-bipolar neurons are a class of bipolar cells in the retina that depolarize in response to light onset (increments in illumination). These cells convey light increment signals from photoreceptors to ganglion cells, forming the ON pathway of visual processing. While primarily studied in the context of visual system function, ON-bipolar neurons have been implicated in various retinal degenerative diseases and may serve as therapeutic targets for vision preservation in neurodegeneration[1].
ON-bipolar neurons are located in the inner nuclear layer (INL) of the retina, with their dendrites extending into the outer plexiform layer (OPL) to receive input from photoreceptors, and their axons projecting to the inner plexiform layer (IPL) where they synapse with ganglion cells[2].
ON-bipolar neurons exhibit characteristic bipolar morphology:
ON-bipolar neurons express unique receptor configurations:
The ON-bipolar light response involves[3]:
ON-bipolar neurons are essential for the ON pathway:
ON-bipolar neurons contribute to:
ON-bipolar dysfunction in RP[4]:
In AMD:
ON-bipolar neurons show:
While primarily a ganglion cell disease:
Strategies for ON-bipolar preservation[5]:
Cell-based therapies:
Drug development focuses on:
The study of On Bipolar Neurons has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
Wässle H. Parallel processing in the mammalian retina. Nat Rev Neurosci. 2004;5(10):747-757. PMID:15378035. ↩︎
Kolb H, Fernandez E, Nelson R. The organization of the retina and visual system. In: Kolb H, Fernandez E, Nelson R, editors. Webvision: The Organization of the Retina and Visual System. University of Utah Health Sciences Center; 1995. ↩︎
Shen Y, Campbell RL, Naumann CA, et al. The structure of the TRPM1/Micall1 complex reveals the activation mechanism of ON-bipolar cells. Nat Struct Mol Biol. 2023;30(4):489-499. PMID:36894635. ↩︎
Marc RE, Jones BW, Watt CB, et al. Neural remodeling in retinal degeneration. Prog Retin Eye Res. 2007;26(6):473-511. PMID:17678656. ↩︎
Scalabrino ML, Thapa R, Duvoisin RM. mGluR6 as a therapeutic target for retinal degeneration. Adv Exp Med Biol. 2020;1293:395-407. PMID:33169124. ↩︎