Role of L-arginine/nitric oxide pathway in the antidepressant effects of ketamine / 中华行为医学与脑科学杂志

ABSTRACT

ObjectiveTo study the role of L-arginine/nitric oxide (NO) pathway in the antidepressant effects of ketamine.MethodsForty two male Wistar rats (200-250 g) were equally randomized into 7 groups ( n =6 )control group ( C group ),L-Arginine ( a precursor of NO ) group ( LA group),L-NAME ( an non-selectivity inhibitor of NO synthase) group ( LN group),ketamine 3 mg/kg group ( K3 group),ketamine 10 mg/kg group (K10 group),L-Arginine + ketamine 10 mg/kg group(LAK10 group),L-NAME + ketamine 3 mg/kg group (LNK3 group).The forced swimming test (FST) of 15 min (pre-test session) was used to establish a rat depression model,then twenty-four hours later FST (test session) was carried out of 6 min and the immobility time in last 5 min was recorded. All the groups were pretreated with saline 1.0 ml,L-arginine 750 mg/kg or L-NAME 30 mg/kg 90 min before FST.Saline 1.0 ml,ketamine 3.0 mg/kg or ketamine 10.0 mg/kg were injected 60 min before FST.The content of hippocampal NO was detected immediately after ethology measurement.ResultsCompared with C group (immobility time( 139.0 ± 27.6)s),the immobility time decreased significantly (( 85.5 ± 34.2),(91.3 ±31.6)s) in K10 group and LNK3 group (P＜0.05),K3 group,LA group,LAK10 group and LN group had no significant difference (P＞0.05) ;compared with C group ( (0.61 ±0.21 ) μmol/gProt),the content of NO increased in LA group ( ( 1.09 ±0.39) μmol/gProt) and decreased in K10 group and LNK3 group significantly( (0.28 ± 0.12),(0.31 ± 0.14 ) μmol/gProt) (P ＜ 0.05 ),K3 group,LAK10 group and LN group had no significant difference (P ＞ 0.05).ConclusionThe antidepressant effects of ketamine are related to the suppression of L-arginine/nitric oxide pathway.