The topographical distribution of serotoninergic terminals in the spinal cord of the cat: biochemical mapping by the combined use of microdissection and microassay procedures

doi:10.1016/0006-8993(77)90680-1

Brain Research

Volume 138, Issue 3, 23 December 1977, Pages 393-406

https://doi.org/10.1016/0006-8993(77)90680-1 Get rights and content

Abstract

The topographical distribution of 5-HT in the spinal cord of the cat was established by the combined use of a microdissection technique and an enzymic microassay for the indoleamine. The procedure consisted of determining the 5-HT content in microdiscs of tissue (0.07 cu.mm) punched out in various zones of frontal sections of the spinal cord at the level of the cervical and lumbar enlargements. In both cases, the concentration of 5-HT in the grey matter was at least twice as high as that in the white matter. The motoneuron area of the ventral horn contained the highest level of 5-HT (402–472 pg) in both enlargements. In the dorsal horn 5-HT was particularly concentrated in the lateral part of the substantia gelatinosa, where its level (∼-320pg) reached about 75 % that found in the motoneuron area. A close value for 5-HT concentration (337–357 pg) was measured in the central area bordering the ependymal canal. A thoracic transection (Th_9–10) induced a progressive decay in 5-HT concentrations below the lesion without altering that found in cervical enlargement. A time-course study has shown that 5-HT was almost undetectable in the lumbar enlargement on the 21st day after the thoracic transection. The selective electrolytic lesion of the nucleus raphe dorsalis did not alter the levels and distribution of 5-HT in the lumbar enlargement. In contrast, a partial lesion of the nucleus raphe magnus (40%) induced a significant decrease in 5-HT levels in this region. This effect was particularly pronounced in the dorsal horns where the 5-HT levels in the substantia gelatinosa were reduced by 44%.

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^*: Present address: INSERM, Unite´de Recherche de Neurophysiologie Pharmacologique, 2 rue d'Ale´sia, 75014 Paris, France.

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The topographical distribution of serotoninergic terminals in the spinal cord of the cat: biochemical mapping by the combined use of microdissection and microassay procedures

Abstract

Brain Research

Brain Research

Brain Research

Brain Research

Brain Research

Pharmacol. Res. Commun.

Brain Research

Neuropharmacology

Brain Research

Brain Research

J. biol. Chem.

Pain

Brain Research

Brain Research

Brain Research

Brain Research

Brain Research

Brain Research

Neuropharmacology

Brain Research

Brain Research

Brain Research