Identification of Morphine Accumulation in the Rat Embryo Central Nervous System: A C14-Morphine Administration Study

BACKGROUND: Previous studies have shown that morphine consumption during pregnancy may cause delay or defect of embryo development or abnormal nervous system function in the human and animal models. In the present study, the highest density of morphine accumulation in the central nervous system of rat embryos was evaluated using C14-morphine. METHODS: Female Wistar rats (W 170-200 g) used and were crossed with male rats and coupling time was recorded (Embryonic day 0-E0). Experimental groups received 0.05 mg/ml of C14-morphine in drinking water daily. On the 10(th) and 17(th) days of pregnancy, pregnant rats were anesthetized and the embryos with these uterus and placenta were surgically removed and were fixed in formalin 10% for 4 week. Then the embryos were processed, sectioned in 25 μm and 5 μm thicknesses, fixed on the glasses for further evaluations. The sectioned in 25, the glasses were fixed on the Blanc black and white film for 6 h. Then, the films were appeared and their negatives were prepared. The sectioned in five staining hematoxylin and eosin by light microscope and MOTIC software. RESULTS: Our results indicated that the highest C14-morphine accumulation was observed in the vesicles and the ventricular choroid plexus (CP) of (E17) embryos, whereas, in the (E10) embryos. Highest concentration was observed in the brain vesicles and the ventricular CP. In addition, this study showed the surface area of lateral, 3(rd) and 4(th) ventricular CP in the experimental groups were increased in compared to control groups. CONCLUSIONS: Our results indicated that effects of morphine on reduction of embryos brain development may be due to the highest accumulation of C14-morphine in the CP and brain vesicles.