Aj. Grottick et al., The alpha(4)beta(2) agonist SIB 1765F, but not the alpha(7) agonist AR-R 17779, cross-sensitises to the psychostimulant effects of nicotine, PSYCHOPHAR, 150(2), 2000, pp. 233-236
Rationale: Repeated administration of nicotine leads to an augmentation of
its locomotor activating effects. Although studies have begun to identify t
he nicotinic receptor subtype(s) mediating the psychostimulant properties o
f nicotine, none as pet have investigated the subtypes which contribute to
the process of sensitisation. Objectives: We therefore investigated cross-s
ensitisation to nicotine using subjects chronically treated with two nicoti
ne subtype-selective agonists in an attempt to identify the relative contri
bution of each to the sensitisation process. Methods. Rats received ten dai
ly injections of either vehicle, nicotine (0.4 mg/kg), the alpha(7)-agonist
AR-R 17779 (20 mg/kg), or the alpha(4)beta(2)-agonist SIE 1765F (3 mg/kg),
and their subsequent locomotor response to acute challenge with each of th
ese compounds was assessed. Results: Chronic administration of both nicotin
e and SIE 1765F3 but not AR-R 17779, resulted in an enhanced locomotor resp
onse to acute challenge with either nicotine or SIE 1765F but not AR-R 1777
9. Conclusions: These data support a role for the alpha(4)beta(2) receptor
in both the initiation and expression of sensitisation to the psychomotor s
timulant effects of nicotine.