Effect of Coriandrum Sativum L. Leaf Extract on the Brain GABA Neurons in Mice

We have evaluated the mechanism underlying the sedative effects of coriander (Coriandrum sativum L.) using a behavioral study and real-time PCR (RT-PCR). The experimental mice were divided as: (1) control, (2) coriander leaf extract400 or 600 mg/kg, (3) coriander seed extract400 or 600 mg/kg, (4) main ingredients. Two hours after oral administration of coriander extracts and main ingredients, a light anesthesia (21.6 mg/kg) of pentobarbital was administered intraperitoneally (i.p.) to all mice. The time points recorded after i.p. administrations were1: immediately after administration, 2: start time of somnolence, 3: end time of somnolence. The brains were isolated from the control and coriander leaf extract groups two hours after oral administration for RT-PCR. Pentobarbital-induced somnolence duration time was compared with that of the control group. A significant difference was found in leaf and seed extract600 mg/kg group and linalool (main ingredient of coriander) group. RT-PCR results showed that the gene expression of GABAA receptor β1 subunit was significantly increased and the gene expression of GABA transporter was significantly decreased in leaf extract 600 mg/kg group. This indicates that the sedative effect of coriander leaf extract is due to the hyperactivity of inhibitory neurons in the brain.