Quantified distribution of the noradrenaline innervation in the hippocampus of adult rat

Journal Article · Wed Nov 01 00:00:00 EST 1989 · Journal of Neuroscience; (USA)

OSTI ID:5037836

Oleskevich, S; Descarries, L; Lacaille, J C ^[1]

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1. Universite de Montreal, Quebec (Canada)

A recently developed radioautographic technique, based on the uptake labeling of monoamine terminals in vitro, was used to quantify the noradrenaline (NA) innervation in adult rat hippocampus. After incubation of brain slices with 1 microM 3H-NA, the NA varicosities were visualized as small aggregates of silver grains, in light microscope radioautographs prepared at 3 equidistant horizontal levels across the ventral 2/3 of the hippocampus. Using a computer-assisted image analyzer, counts were obtained from the subiculum (SUB), 3 sectors of Ammon's horn (CA1, CA3-a, CA3-b) and 3 sectors of the dentate gyrus (DG-medial blade, crest, and lateral blade), every lamina being sampled in each region. After a double correction for duration of radioautographic exposure and section thickness, and following measurement of varicosity diameter in electron microscope radioautographs, it was possible to express these results in number of terminals per volumetric unit of tissue. It was thus found that the overall density of hippocampal NA innervation averages 2.1 million varicosities/mm3 of tissue, a value almost twice as high as that in cerebral cortex. This innervation is 20% denser ventrally than dorsally and is heterogeneous both in terms of regional and laminar distribution. SUB and DG are more strongly innervated than Ammon's horn, wherein CA1 has the lowest overall density. In SUB and CA1, there is a clear predilection of NA varicosities for the stratum moleculare. In CA3, there is a narrow band of even stronger innervation in the stratum radiatum, near the apical border of the stratum pyramidale, contrasting with a 3 times lower density in this cell layer and the stratum oriens. In DG, the NA innervation is again the weakest in the cell body layer and exhibits an almost 3-fold greater density in the polymorph layer, the highest of all hippocampus.

• OSTI ID: 5037836
• Journal Information: Journal of Neuroscience; (USA), Vol. 9:11; ISSN 0270-6474
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
HIPPOCAMPUS
AUTORADIOGRAPHY
NORADRENALINE
TISSUE DISTRIBUTION
IN VITRO
RATS
TRITIUM COMPOUNDS
ADRENAL HORMONES
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
BODY
BRAIN
CARDIOTONICS
CARDIOVASCULAR AGENTS
CENTRAL NERVOUS SYSTEM
DISTRIBUTION
DRUGS
HYDROGEN COMPOUNDS
MAMMALS
NERVOUS SYSTEM
NEUROREGULATORS
ORGANS
RODENTS
SYMPATHOMIMETICS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques