African Journal of Biomedical Research

Log in or Register to get access to full text downloads.

Remember me or Register

Adrenergic Component of Nicotine Antinociception in Rats

GF Ibironke, OA Oyekunle


It has been widely established that nicotine , the active pharmacological agent in tobacco has antinociceptive effects , but the mechanism of this activity is yet to be fully investigated . The present study examined the effects of two adrenergic receptor antagonists , propranolol and prazosin .on nicotine antinociception using the hot plate (HP) paradigm in adult male Wister rats ( 180-220gm ) . Three groups of rats received respectively , first , saline ( 10ml/kg) intraperitoneally ( ip) plus intravenous ( iv) nicotine (1ml/kg ) , second , propranolol ( 10-30mg/kg, ip ) plus nicotine and the last group had prazosin (0.2- 1.0mg/kg , ip ) followed by the same dose of nicotine .Nociception was measured at 15 mins intervals for one hour . While the administration of normal saline had no effect on the supraspinally mediated hot plate latencies , both propranolol and prazosin reduced the hot plate responses ( significant at 15 , 30 ,45 and 60 mins , post injection) .These findings suggest the involvement of the adrenergic system in nicotine induced antinociception .

Keywords: propranolol, prazosin, antinociception, hot plate

AJOL African Journals Online