Elsevier

Neuroscience

Volume 53, Issue 2, March 1993, Pages 465-473
Neuroscience

5-Hydroxytryptamine1 recognition sites in rat brain: Heterogeneity of non-5-hydroxytryptamine1a/1c binding sites revealed by quantitative receptor autoradiography

https://doi.org/10.1016/0306-4522(93)90210-7Get rights and content

Abstract

Quantitative in vitro receptor autoradiography was used to characterize the [3H]5-hydroxytryptamine binding sites which are not sensitive to 8-hydroxy-2-(di-N-propylamino)tetralin, mesulergine and serotonin-5-O-car☐y-methyl-glycyl-tyrosinamide, in a non-5-hydroxytryptamine1A/1B/1C/1D receptor population, in rat brain.

Displacement of [3H]5-hydroxytryptamine [in the presence of 100nM 8-hydroxy-2-(di-N--propyl-amino)tetralinandmesulergine, to block 5-hydroxytryptamine1A and 5-hydroxytryptamine1C sites] with (-)pindolol, 5-hydroxy-3(4-1,2,5,6-tetrahydropyridyl)-4-azaindole, sumatriptan and serotonin-5-O-car☐y-methyl-glycyl-tyrosinamide yielded complex competition curves suggesting the presence of 5-hydroxytryptamine1B and 5-hydroxytryptamine1D sites and an additional [3H]5-hydroxytryptamine-sensitive component in rat brain. The non-5-hydroxytryptamine1n1A/1B/1C/1D binding sites were localized in olfactory tubercle, several nuclei of the amygdala, bed nucleus of the stria terminalis, caudate-putamen, CA3 field of the hippocampus, the frontoparietal cortex (motor area) and parts of the striate cortex. All the drugs used had low affinity for the unknown recognition site, which therefore might be comparable to the [3H]5-hydroxytryptamine binding site reported to display low affinity for sumatriptan and 5-car☐amidotryptamine in the brains of various species, the so-called 5-hydroxytryptamine1E site.

A comparison of the density of sites labelled with [125I]serotonin-5-O-car☐y-methyl-glycyl-tyrosinamide (representing 5-hydroxytryptamine1B and 5-hydroxytryptamine1D sites) and [3H]5-hydroxytryptamine (under the conditions mentioned above) showed the density of [3H]5-hydroxytryptamine recognition sites to be higher in some structures.

It is concluded that in addition to the 5-hydroxytryptamine1B and 5-hydroxytryptamine1D, an uniden tified 5-hydroxytryptamine binding site is labelled with [3H]5-hydroxytryptamine, in the presence of 5-hydroxytryptamine1A and 5-hydroxytryptamine1C blocking agents, in several structures of the rat brain. Since the compounds tested displayed very low affinity for this site, the availability of high-affinity ligands would certainly facilitate further characterization of this [3H]5-hydroxytryptamine recognition site, which may correspond to the 5-hydroxytryptamine1E site.

References (28)

  • BoulenguezP. et al.

    Biochemical and pharmacological characterization of serotonin-O-car☐ymethylglycyl[125I]iodotyrosinamide, a new radioiodinated probe for 5-HT1B and 5-HT1D binding sites

    J. Neurochem.

    (1992)
  • BruinvelsA.T. et al.

    5-HT1D binding sites in various species: similar pharmacological profile in calf, guinea-pig, dog, monkey and human brain membranes

    Naunyn-Schmiedeberg's Arch. Pharmac.

    (1992)
  • BruinvelsA.T. et al.

    Pharmacological characterization and localization of 5-HT1B and 5-HT1D-like recognition sites in rat brain

  • DumuisA. et al.

    A non-classical 5-hydroxytryptamine receptor positively coupled with adenylate cyclase in the central nervous system

    Molec. Pharmac.

    (1988)
  • Cited by (32)

    • Serotonin modulation of the basal ganglia circuitry: therapeutic implication for Parkinson's disease and other motor disorders

      2008, Progress in Brain Research
      Citation Excerpt :

      Similarly to 5-HT1B receptors, some authors described a discrepancy in the distribution pattern of 5-HT1D mRNA and its protein in the striatum, SN and GP of mouse brain and therefore hypothesized a presynaptic localization of 5-HT1D receptors in the latter two areas (Boschert et al., 1994). Finally, regarding the 5-HT1 receptor family, Bruinvels et al. (1993b) reported the presence of the 5-HT1E receptor subtype mRNA in both the caudate nucleus and putamen of primates, showing stronger hybridization signals in monkey brain than that obtained in human brain. Both 5-HT2A receptor subtype and its mRNA have been extensively demonstrated to be present in the striatum of various mammal species.

    • Serotonin and the Orchestration of Energy Balance

      2007, Cell Metabolism
      Citation Excerpt :

      Through widespread projections to regions that include the hypothalamus, amygdala, and brainstem, it participates in the regulation of feeding, drinking, respiration, and cardiovascular function (Saper and Loewy, 1980). The PBN receives serotonergic innervation from the dorsal raphe nucleus and area postrema (Petrov et al., 1992; Simansky and Nicklous, 2002) and expresses both 5-HT2CRs and 5-HT1BRs (Bruinvels et al., 1993; Wright et al., 1995). An important contribution of the PBN to dFen-induced anorexia is indicated by the ability of PBN lesions to suppress this effect (Li et al., 1994).

    • 5-HT-1E receptor

      2007, xPharm: The Comprehensive Pharmacology Reference
    • Central 5-HT<inf>1</inf> and 5-HT<inf>2</inf> binding sites in transgenic mice with reduced glucocorticoid receptor number

      2000, Brain Research
      Citation Excerpt :

      Other sections were treated the same way but incubated in the presence of 2 nM [3H]5-HT, added with 100 nM 8-OH-DPAT and 100 nM mesulergine which prevent the labelling of 5-HT1A and 5-HT2C sites, respectively. This way, all 5-HT1nonA sites were labelled, i.e. 5-HT1B, 5-HT1D, 5-HT1E and 5-HT1F subtypes, although in mice and rats 5-HT1B are predominant in most structures [8]. These sections were then rinsed 3×20-s, dried and exposed for about 1 month.

    View all citing articles on Scopus
    *

    Present address: Departemento de Neuroquimica, C.I.D., C.S.I.C., Jordi Girona 18-26, Barcelona 08034, Spain.

    View full text