Effect Of Morphine Addiction And Withdrawal In Parents Prior To Mating On Foraging Behavior In Adult Offspring Rats

Objective To observe the effects and possible mechanisms of the experience of morphine addiction and withdrawal on foraging behavior prior to mating in adult offspring rats.Methods 8 weeks old healthy Sprague-Dawleyda rats were used.the total number is 40 rats (20 male and 20 female).20 rats were intraperitoneal injected of morphine 10 d,2 times/d, the starting dose is 5 mg/kg,5 mg daily increasing to 50 mg/kg on the tenth day; the other 20 rats were injected with the same dose of saline with the same method. 21 days after Withdrawal, male and female rats were coupled, Group 1: addicted males+addicted females; group 2:addicted males+saline females; group 3:saline males+addicted females; group 4:saline males+saline females. There are three males and three females within each group,. When the offspring is 8 weeks old, the foraging behavior tests were assessed, get brains,conduct Golgi staining and analysis neuronal morphology of anterior cingulate cortex (ACC) quantitatively after the completion of all behavioral tests. Use Neurolucida software (MicroBrightField, USA) reconstruct the 3D of dendritic neurons into two-dimensional, then detect the numbers of dendritic branch points, dendritic branch length and branch density of dendritic spines.Results foraging test results:the amount of predation (g)of male and female offsprings of groupl,2,3 per 12 h were [respectively (43.8+ 10.75,41.3±9.67,95.9±18.34,40.3±13.15.86.7±16.60,42.0±18.44)], lower than the amount of group 4 (183.81±17.74,201.84±11.12)(p<0.001). Golgi-Cox staining results:the numbers of apical dendrites branches in anterior cingulate cortex neurons of male and female offsprings in group 1,2,3 were[respectively (13.1±4.11,9.6±2,3,11.6±2.06,9.8±5.02,10.8±3.25,12.5±6.60)], the total length of apical dendrites branch (μm) [respectively (1181.3±59.73,1201.7±118.56,1338.6±137.58,1351.7±129.24,1404.5±178.47,1373.7±226.94)] and apical dendritic spine density (a/10μm) [respectively (3.2±0.18,3.0±0.41,3.1±0.65,2.8±1.11,2.9±0.52,3.2+1.30)], lower than those of group 4 [(21.4±6.80,25.8±7.1,2206.1±381.40,2292.3±335.48,6.0±0.71,5.8±1.02)] (p<0.05). parameters of basic dendrites in anterior cingulate cortex neurons of all Offspring groups have no significant difference (p> 0.05).Conclusion The experience of morphine addiction and withdrawal prior to mating will lead to disorders in offsprings predation behavior, which may be related to poor development of dendritic morphology in anterior cingulate cortex neurons in the offsprings.