Background & Objectives: Reports suggest that co-administration of Matricaria Chamomilla (MC) extract with morphine greatly attenuates the dependence on morphine and its injection prior to naloxan inhibits the withdrawal syndrome. Locus Ceruleus (LC) and paragigantocellularis (PGi) nuclei play a key role in appearance of withdrawal syndrome. Thus, this study was conducted to determine the effects of MC extract injection into pGi nucleus on morphine withdrawal in rats.
Materials & Methods: 30 rats (Weighing 250-300gr) were divided into two groups of control (receiving saline) and morphine- treated. Following surgical implantation of cannula, morphine- treated group received morphine twice daily for 7 days. This group was classified into 4 sub-groups. The first sub-group received only morphine while the three remaining sub-groups were administed with Matricaria Chamomilla on day 7, five minutes prior to 1 microliter naloxan injection, with 10, 25, and 50 microgr/lit, respectively. In all groups 5 mg/kg naloxan was injected 3 hours after the final injection of morphine and withdrawal behavior (jumping and climbing) was investigated for 30 minutes.
Results: The results showed that injection of all three high doses of MC extract particulary 25 microgr/microlit into PGi nuclens could significantly decline the symptoms of withdrawal syndrome.
Conclusion: It seems that injection of MC extract into PGi nucleus could be beneficial to the treatrnent of morphine withdrawal syndrome in rats.