The effect of morphine consumption on plasma corticosteron concentration and placenta development in pregnant rats

BACKGROUND Previous studies have shown that morphine consumption during pregnancy may delay embryo development or cause abnormal nervous system function. OBJECTIVE The present study focused on the effect of maternal morphine consumption on development of placenta and blood corticosteron concentration in addictive pregnant mothers. MATERIALS AND METHODS 24 female rats, 170-200g weight, were used. The experimental groups after pregnancy received an oral dose of 0.05 mg/ml of morphine by tap water while the control group received only tap water. On 10(th) and 14(th) day of pregnancy, rats were anesthetized and placenta removed surgically, 1ml blood was collected from each pregnant mother from retro-orbital sinus, the concentration of blood corticosteron was determined by corticosteron Elisa kit after centrifugation. The fixed tissue was processed, sectioned and stained with hematoxylin and eosin. Placenta was studied microscopically according to the thickness of layers, area of blood cisterns, and the number of cells. RESULTS Comparing the plasma corticosteron concentration of the treatment and the control groups, not only a severe increase in the treatment group was detected, but also the thickness of maternal and embryonic portions of the placenta at day 10(th) and 14(th) of gestation was different significantly (p≤0.05). Furthermore, an increase in number of cells in maternal and embryonic portion of placenta and a decrease in blood cistern area were demonstrated in both the experimental and the control groups. CONCLUSION The effects of morphine, including an increase in blood concentration of corticosteron, in dependent pregnant mothers were seen. Development of placenta in the experimental group was delayed.