Modulating mGluR5 in Adult Mice

Mice received a daily intraperitoneal injection (at 9 am) from the postnatal day 56 (PnD56) to PnD91 during 5 weeks, see Fig 1. Negative allosteric modulator of mGluR5, 3-((2-methyl-4-thiazolyl)ethynyl)pyridine (MTEP), (2 mg/ml, 3 mg/kg animal, Tocris, Cat. No. 2921) and positive allosteric modulator of mGluR5, 3-Cyano-N-(1,3-diphenyl-1H-pyrazol-5-yl) benzamide (CDPPB), (6.66 mg/ml, 10 mg/kg animal, Tocris, Cat. No. 3235) solutions were prepared with the same dissolving solution (accordingly to manufacturer’s recommendation). Drug preparation was made so that each animal received equivalent volume (1.5 μl/g animal). Equivalent volume of dissolving solution was used for the control treatment. Fresh solutions were prepared every 2–3 days and preserved at 4°C. The CDPPB and MTEP doses used in this study are known to be active at the behavioral and cellular level [5 (link), 40 (link)–43 (link)]. Since mGluR5 is known to play a function during the cerebral development and in the adult brain, the treatment was started in adulthood to exclude the effect of mGluR5 on development and, consequently, limiting the present results to the effect of mGluR5 in mature/adult brain.