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Immunohistochemical and Calcium Imaging Methods in Wholemount Rat Retina
Published on: October 13, 2014
Histamine immunoreactive axons in the macaque retina
M J Gastinger1, J J O'Brien, N B Larsen
1Department of Neurobiology and Anatomy, University of Texas-Houston Medical School, 77030, USA.
Investigative Ophthalmology & Visual Science
|February 9, 1999
Summary
Histamine is the neurotransmitter in centrifugal axons of the macaque retina, originating from the hypothalamus. These axons may regulate retinal function and blood vessels.
Area of Science:
- Neuroscience
- Ophthalmology
- Neurochemistry
Background:
- Centrifugal axons in the primate retina are not well understood.
- The neurotransmitter identity of these axons remains to be elucidated.
Purpose of the Study:
- To identify the neurotransmitter within centrifugal axons in the macaque retina.
- To investigate the origin and distribution of these axons.
Main Methods:
- Immunofluorescence technique using antiserum to histamine.
- Carbodiimide fixation of macaque retinas and optic nerves.
Main Results:
- Histamine-immunoreactive axons were identified originating from the optic nerve head and projecting to the inner plexiform layer.
- Axons formed extensive networks in the peripheral retina and circled the fovea.
- No histamine-labeled cell bodies were found in the retina, suggesting a hypothalamic origin.
Conclusions:
- Centrifugal axons in the macaque retina contain histamine and originate in the hypothalamus.
- Histamine may prepare the retina for daylight function and regulate retinal microvasculature.
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