Repeated systemic (s.c.)injections of L-acetylcarnitine (LAC), an epigenetic drug that potentiates the transcription the gene encoding for mGluR2 (GRM2), reduced thermal hypersensitivity in sham control rats and mechanical allodynia (von Frey) in neuropathic (CCI and diabetes induced by streptozotocin) and inflammatory (CFA) pain conditions through a mechanism that involved increased expression of mGluR2 in the dorsal horn and DRG in both conditions [101,103]. This evidence concerns the gene GRM2 and diabetes mellitus.