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David W. Marshak, Ph.D.

Professor

Telephone: 713.500.5617
E-mail: david.w.marshak@uth.tmc.edu
Downloads: Curriculum Vitae [ pdf ]

Histamine effects on retinal neurons

Centrifugal axons in macaque retina labeled with antibody to histamine.

The retinas of all mammals, including humans, receive inputs from neurons in the brain, but these neurons are not specialized for vision.  They are part of the ascending arousal system, projecting throughout the central nervous system and firing tonically while the animal is awake.  One of the neurotransmitters in this pathway is histamine, and Dr. Marshak is studying how histamine contributes to information processing in primate and rodent retinas.  He and his collaborators use light and electron microscopic immunolabeling techniques to localize histamine receptors in the retina.  Based on those results, they design electrophysiological experiments to study the mechanisms underlying the effects of histamine on local circuit neurons.  In primates, histamine hyperpolarizes ON bipolar cells and enhances their voltage-dependent potassium conductance via histamine receptor 3.  They are now studying the effects of histamine on cones, which express histamine receptor 2, and horizontal cells, which express histamine receptor 1.  Histamine also decreases the sensitivity of many retinal ganglion cells, the projection neurons of the retina.  This finding suggests that histamine mediates a component of light adaptation in primates. In nocturnal animals such as rodents, histamine is released at night, and its receptors are found on different retinal neurons.  In rats, dopaminergic amacrine cells express histamine receptor 1, and histamine inhibits the release of dopamine.  Because light stimulates dopamine release and dopamine mediates many effects of light adaptation, these findings suggest that histamine contributes to dark adaptation in rodents.  Taken together, these results suggest that the inputs from the brain optimize retinal function during the conditions prevailing when the animal is most active.

Selected Reading

Gastinger, MJ, Vardi, N, Marshak, DW. (2006) Histamine receptors in mammalian retinas. Journal of Comparative Neurology 495:658-667.

Bordt, AS, Hoshi H, Yamada, ES, Perryman-Stout, WC, Marshak, DW. (2006) Synaptic input to OFF parasol ganglion cells in macaque retina. Journal of Comparative Neurology 498:46-57.

Miller, .JA, Denning, KS, George, JS, Marshak, DW, Kenyon, GT. (2006) A high frequency resonance in the responses of retinal ganglion cells to rapidly modulated stimuli: a computer model. Visual Neuroscience 23, 779-794.

Gastinger, MJ, Tian, N, Horvath, TN, Marshak, DW. (2006) Retinopetal axons in mammals: emphasis on histamine and serotonin. Current Eye Research, 31:655-667.

Marc, RE, Jones, BW, Anderson, JR, Kinard, K, Marshak, DW, Wilson, JH, Wensel, T, Lucas, RJ. (2007) Neural reprogramming in retinal degeneration. Investigative Ophthalmology and Visual Science 48:3364-3371.

Lebedev, DS, Marshak, DW. (2007) Amacrine cell contributions to red-green color opponency in central primate retina: a model study. Visual Neuroscience 24:535-547.

Mills, SL, Xia, XB, Hoshi, H, Firth, SI, Rice, ME, Frishman, LJ, Marshak, DW. (2007) Dopaminergic modulation of tracer coupling in a ganglion-amacrine cell network. Visual Neuroscience 24, 593-608.

Search PubMed for additional articles.