“School of Cognitive Sciences”

Back to Papers Home
Back to Papers of School of Cognitive Sciences

Paper   IPM / Cognitive Sciences / 7445
School of Cognitive Sciences
  Title:   Role of nitric oxide in the acquisition and expression of apomorphine- or morphine-induced locomotor sensitization
  Author(s): 
1.  M.R. Zarrindast
2.  A. Gholami
3.  H. Sahraei
4.  A. Haeri Rohani
  Status:   Published
  Journal: EUR J PHARMACOL
  No.:  482
  Year:  2003
  Pages:   205-213
  Supported by:  IPM
  Abstract:
In the present study, the effects of L-arginine, a nitric oxide (NO) precursor, and N(G)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase (NOS) inhibitor, on apomorphine- or morphine-induced locomotor sensitization in male albino mice were investigated. Our data showed that subcutaneous (s.c.) injection of apomorphine (2-10 mg/kg) or morphine sulphate (5-50 mg/kg) significantly increased locomotor behaviour in a dose-dependent manner. Intraperitoneal (i.p.) administration of L-arginine (100 mg/kg) increased locomotor activity, whereas L-NAME (20 mg/kg) decreased it. L-Arginine and L-NAME increased and decreased apomorphine- or morphine-induced locomotions, respectively. The locomotor behavioural response was enhanced in mice pretreated with apomorphine (2 mg/kg, daily x3 days) or morphine (10 mg/kg, daily x3 days) alone, indicating that sensitization had developed. Administration of L-arginine 30 min before each of three daily doses of apomorphine or morphine increased the development of sensitization, while administration of L-NAME 30 min before each of three daily doses of apomorphine or morphine decreased the acquisition of sensitization induced by apomorphine or morphine. Administration of L-arginine significantly increased and L-NAME significantly and dose-dependently decreased the expression of both apomorphine- and morphine-induced sensitization. The results indicate that NO may be involved in the acquisition and expression of apomorphine- or morphine-induced sensitization

Download TeX format
back to top
scroll left or right