RATIONALE: Male wild house-mice genetically selected for long attack latency (LAL) and short attack latency (SAL) differ in structural and functional properties of postsynaptic serotonergic-1A (5-HT(1A)) receptors. These mouse lines also show divergent behavioral responses in the forced swimming test (FST, i.e., higher immobility by LAL versus SAL mice). OBJECTIVES: We investigated whether the line difference in 5-HT(1A) receptors is associated with a difference in brain 5-HT metabolism, and whether acute administration of a 5-HT(1A) receptor agonist could differentially affect the behavioral responses of LAL and SAL mice. METHODS: 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) levels were measured in homogenates of several brain regions using high-performance liquid chromatography. The behavioral effect of the full 5-HT(1A) receptor agonist, 8-OH-DPAT, and of the somatodendritic 5-HT(1A) autoreceptor agonist, S-15535, was examined in the FST. The effect of 8-OH-DPAT on forced swimming-induced 5-HT metabolism in brain homogenates was determined. RESULTS: In most brain regions, 5-HT and 5-HIAA levels and 5-HT turnover were not significantly different between LAL and SAL mice. 8-OH-DPAT abolished the behavioral line difference in the FST by reducing immobility in LAL mice and reducing climbing in SAL mice. S-15535 induced a similar behavioral effect to 8-OH-DPAT in SAL mice, but did not alter the behavior of LAL mice. Compared with LAL, forced swimming elicited in SAL mice a higher brain 5-HT turnover, which was potently attenuated by 8-OH-DPAT. CONCLUSIONS: It is unlikely that the difference in 5-HT(1A) properties between LAL and SAL mice is an adaptive compensatory reaction to changes in 5-HT metabolism. Although unspecific motor effects, at least in SAL mice, cannot be ruled out, it is suggested that the behavioral effects of 8-OH-DPAT and S-15535 may be mediated by predominant activation of postsynaptic 5-HT(1A) receptors in LAL mice and by presynaptic 5-HT(1A) receptors in SAL mice.
RATIONALE: Male wild house-mice genetically selected for long attack latency (LAL) and short attack latency (SAL) differ in structural and functional properties of postsynaptic serotonergic-1A (5-HT(1A)) receptors. These mouse lines also show divergent behavioral responses in the forced swimming test (FST, i.e., higher immobility by LAL versus SALmice). OBJECTIVES: We investigated whether the line difference in 5-HT(1A) receptors is associated with a difference in brain 5-HT metabolism, and whether acute administration of a 5-HT(1A) receptor agonist could differentially affect the behavioral responses of LAL and SALmice. METHODS: 5-HT and 5-hydroxyindoleacetic acid (5-HIAA) levels were measured in homogenates of several brain regions using high-performance liquid chromatography. The behavioral effect of the full 5-HT(1A) receptor agonist, 8-OH-DPAT, and of the somatodendritic 5-HT(1A) autoreceptor agonist, S-15535, was examined in the FST. The effect of 8-OH-DPAT on forced swimming-induced 5-HT metabolism in brain homogenates was determined. RESULTS: In most brain regions, 5-HT and 5-HIAA levels and 5-HT turnover were not significantly different between LAL and SALmice. 8-OH-DPAT abolished the behavioral line difference in the FST by reducing immobility in LAL mice and reducing climbing in SALmice. S-15535 induced a similar behavioral effect to 8-OH-DPAT in SALmice, but did not alter the behavior of LAL mice. Compared with LAL, forced swimming elicited in SALmice a higher brain 5-HT turnover, which was potently attenuated by 8-OH-DPAT. CONCLUSIONS: It is unlikely that the difference in 5-HT(1A) properties between LAL and SALmice is an adaptive compensatory reaction to changes in 5-HT metabolism. Although unspecific motor effects, at least in SALmice, cannot be ruled out, it is suggested that the behavioral effects of 8-OH-DPAT and S-15535 may be mediated by predominant activation of postsynaptic 5-HT(1A) receptors in LAL mice and by presynaptic 5-HT(1A) receptors in SALmice.
Authors: S M Korte; O C Meijer; E R de Kloet; B Buwalda; J Keijser; F Sluyter; G van Oortmerssen; B Bohus Journal: Brain Res Date: 1996-10-14 Impact factor: 3.252
Authors: Anthony L Berger; Angela M Henricks; Janelle M Lugo; Hayden R Wright; Collin R Warrick; Martin A Sticht; Maria Morena; Itziar Bonilla; Sarah A Laredo; Rebecca M Craft; Loren H Parsons; Pedro R Grandes; Cecilia J Hillard; Matthew N Hill; Ryan J McLaughlin Journal: Biol Psychiatry Date: 2018-05-08 Impact factor: 13.382