Autoradiographic studies of selective amino acid uptake by neural and nonneural elements in the gerbil cochlea.
The cochlea is well suited for studies of the uptake properties of auditory neurons and nonneuronal supporting cells. Probe concentrations of radioisotopically labeled amino acids, including putative neurotransmitters and their precursors, breakdown products, and blockers, can be introduced via the natural, fluid-filled channels of the inner ear. Uptake patterns can be mapped at cellular and intracellular levels using light and electron microscopic autoradiographic methods. The procedures for introduction of label, fixation, plastic embedment, and light and electron microscopic autoradiography are described with special reference to the cochlea. Labeling patterns observed with over 20 amino acids are summarized for hair cells, spiral ganglion neurons, efferents, and nonneural elements of the stria vascularis, limbus, and modiolus. Limitations on the interpretation of results and their implications for the general usefulness of the methods are discussed.
Schwartz
I R
IR
Section of Otolaryngology, Yale University School of Medicine, New Haven, Connecticut 06510.
Ryan
A F
AF
D000596:Amino Acids / Q000378:metabolism* / Q000502:physiology; D000818:Animals; D001345:Autoradiography / Q000379:methods*; D003051:Cochlea / Q000378:metabolism* / Q000648:ultrastructure; D005849:Gerbillinae; D006198:Hair Cells, Auditory / Q000378:metabolism / Q000648:ultrastructure; D006199:Hair Cells, Auditory, Inner / Q000378:metabolism / Q000648:ultrastructure; D008854:Microscopy, Electron / Q000379:methods; D009475:Neurons, Afferent / Q000648:ultrastructure; D009476:Neurons, Efferent / Q000648:ultrastructure; D018377:Neurotransmitter Agents / Q000378:metabolism; D013136:Spiral Ganglion / Q000378:metabolism / Q000648:ultrastructure; D013316:Stria Vascularis / Q000378:metabolism / Q000648:ultrastructure
D000596:Amino Acids; D018377:Neurotransmitter Agents