Carbaryl is a carbamate insecticide that inhibits acetylcholinesterase (AChE; IC50 = 13.6 nM for A. gambiae AChE2 expressed in Sf9 cells; Ki = 5.7 µM for rat brain AChE).1,2 Carbaryl administered at a dose of 30 mg/kg for 28 days in rats decreases the weight of spleen and thymus, proliferation of lymphocytes, and serum levels of IL-2, IFN-γ, IL-1β, and TNF-α, and increases the serum levels of IL-4 and IL-10.3 It increases CaMKII, GAP-43, and tau protein levels in the hippocampus and tau levels in the cortex of mice 24 hours after administration of doses ranging from 0.5 to 20 mg/kg on postnatal day ten, whereas tau protein levels are decreased four months after administration with no change in CaMKII or GAP-43 compared with control mice. These effects occur at non-toxic doses where acetylcholinesterase is inhibited only during the first six hours following treatment. Formulations containing carbaryl have been used to control insects in agriculture.
1.Zhao, P., Wang, Y., and Jiang, H.Biochemical properties, expression profiles, and tissue localization of orthologous acetylcholinesterase-2 in the mosquito, Anopheles gambiaeInsect. Biochem. Mol. Biol.43(3)260-271(2013) 2.Hassan, A., Abdel-Hamid, F.M., and Bahig, M.R.E.Kinetics of inhibition of rat brain acetylcholinesterase by SevinZ. Naturforsch. B.22(5)505-507(1967) 3.Jorsaraei, S.G., Maliji, G., Azadmehr, A., et al.Immunotoxicity effects of carbaryl in vivo and in vitroEnviron. Toxicol. Pharmacol.38(3)838-844(2014)