Density and function of central serotonin (5-HT) transporters, 5-HT1A and 5-HT2A receptors, and effects of their targeting on BTBR T+tf/J mouse social behavior
Article first published online: 2 DEC 2010
© 2010 The Authors. Journal of Neurochemistry © 2010 International Society for Neurochemistry
Journal of Neurochemistry
Volume 116, Issue 2, pages 291–303, January 2011
How to Cite
Gould, G. G., Hensler, J. G., Burke, T. F., Benno, R. H., Onaivi, E. S. and Daws, L. C. (2011), Density and function of central serotonin (5-HT) transporters, 5-HT1A and 5-HT2A receptors, and effects of their targeting on BTBR T+tf/J mouse social behavior. Journal of Neurochemistry, 116: 291–303. doi: 10.1111/j.1471-4159.2010.07104.x
- Issue published online: 16 DEC 2010
- Article first published online: 2 DEC 2010
- Accepted manuscript online: 10 NOV 2010 12:54PM EST
- Received July 29, 2010; revised manuscript received November 3, 2010; accepted November 3, 2010.
- 5-HT1A receptor;
- CA1 of hippocampus;
J. Neurochem. (2011) 116, 291–303.
BTBR mice are potentially useful tools for autism research because their behavior parallels core social interaction impairments and restricted-repetitive behaviors. Altered regulation of central serotonin (5-HT) neurotransmission may underlie such behavioral deficits. To test this, we compared 5-HT transporter (SERT), 5-HT1A and 5-HT2A receptor densities among BTBR and C57 strains. Autoradiographic [3H] cyanoimipramine (1nM) binding to SERT was 20–30% lower throughout the adult BTBR brain as compared to C57BL/10J mice. In hippocampal membrane homogenates, [3H] citalopram maximal binding (Bmax) to SERT was 95 ± 13 fmol/mg protein in BTBR and 171 ± 20 fmol/mg protein in C57BL/6J mice, and the BTBR dissociation constant (KD) was 2.0 ± 0.3 nM versus 1.1 ± 0.2 in C57BL/6J mice. Hippocampal 5-HT1A and 5-HT2A receptor binding was similar among strains. However, 8-OH-DPAT-stimulated [35S] GTPγS binding in the BTBR hippocampal CA1 region was 28% higher, indicating elevated 5-HT1A capacity to activate G-proteins. In BTBR mice, the SERT blocker, fluoxetine (10 mg/kg) and the 5-HT1A receptor partial-agonist, buspirone (2 mg/kg) enhanced social interactions. The D2/5-HT2 receptor antagonist, risperidone (0.1 mg/kg) reduced marble burying, but failed to improve sociability. Overall, altered SERT and/or 5-HT1A functionality in hippocampus could contribute to the relatively low sociability of BTBR mice.