1 Department of Psychiatry, McGill University, 1033 Pine Avenue West, Montreal, QC, H3A 1A1, Canada.
2 Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, K1H 8M5, Canada.
3 Institute of Mental Health Research, affiliated with the University of Ottawa, Ottawa, ON, K1Z 7K4, Canada.
4 Department of Psychology, Université Laval, Quebec City, QC, G1V 0A6, Canada.
5 CHU Ste-Justine Research Center, Montreal, QC, H3T 1C5, Canada.
6 Department of Psychiatry and Addiction, Université de Montréal, Montreal, QC, H3T 1J4, Canada.
7 Department of Neurology & Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, H3A 2B4, Canada.
8 Department of Psychiatry, McGill University, 1033 Pine Avenue West, Montreal, QC, H3A 1A1, Canada. marco.leyton@mcgill.ca.
9 CHU Ste-Justine Research Center, Montreal, QC, H3T 1C5, Canada. marco.leyton@mcgill.ca.
10 Department of Neurology & Neurosurgery, Montreal Neurological Institute, McGill University, Montreal, QC, H3A 2B4, Canada. marco.leyton@mcgill.ca.
11 Department of Psychology, McGill University, Montreal, QC, H3G 1G1, Canada. marco.leyton@mcgill.ca.
12 Center for Studies in Behavioral Neurobiology, Concordia University, Montreal, QC, H4B 1R6, Canada. marco.leyton@mcgill.ca.

Sex differences in [11C]ABP688 binding: a positron emission tomography study of mGlu5 receptors.

Eur J Nucl Med Mol Imaging. 2019 May;46(5):1179-1183

Authors: Smart K, Cox SML, Scala SG, Tippler M, Jaworska N, Boivin M, Séguin JR, Benkelfat C, Leyton M

Abstract

PURPOSE: The purpose of this study was to assess, in a large sample of healthy young adults, sex differences in the binding potential of [11C]ABP688, a positron emission tomography (PET) tracer selective for the metabotropic glutamate type 5 (mGlu5) receptor.

METHODS: High resolution [11C]ABP688 PET scans were acquired in 74 healthy volunteers (25 male, 49 female, mean age 20?±?3.0). Mean binding potential (BPND?=?fND * (Bavail / KD)) values were calculated in the prefrontal cortex, striatum, and limbic regions using the simplified reference tissue model with cerebellar grey matter as the reference region.

RESULTS: [11C]ABP688 BPND was significantly higher in men compared to women in the prefrontal cortex (p?<?0.01), striatum (p?<?0.001), and hippocampus (p?<?0.05). Whole-brain BPND was 17% higher in men. BPND was not related to menstrual phase in women.

CONCLUSIONS: Binding availability of mGlu5 receptors as measured by PET [11C]ABP688 is higher in healthy men than women. This likely represents a source of variability in [11C]ABP688 studies and could have relevance for sex differences in cognitive-behavioral functions and neuropsychiatric disorders.

PMID: 30627817 [PubMed - in process]