Identification of Site of Morphine Action in Pregnant Wistar Rat Placenta Tissue: A C14 -Morphine Study

objective: in previous studies it has been emphasized that the site of morphine action may be either in the embryo or the placenta. in the present study, we attempt to identify the site of morphine action on the fetal section of wistar rat placenta by using c-morphine.materials and methods: in this study (experimental), female wistar rats (weights: 170-200 g) were mated with male rats and their coupling times recorded. experimental groups receiveddaily doses of 0.05 mg/ml of c14-morphine in their drinking water. on the 9 embryonic days, the pregnant rats were anesthetized and the placenta and uterus surgicallyremoved.placentaswerefixedin10%formalinfortwoweeks,thenprocessed,sectionedin5µmand25µmthicknesses,andfixedonglassslidesforfurtherevaluation.the25µmsectionsweredeliveredtoblackandwhitefilmforthreedays.filmswereprocessedandevaluatedwithadigitalinversemicroscopeforpossibleradiologicalimpression.the5µmsectionswereprocessedforhematoxylinandeosin(h&e)staining,andevaluatedbylightmicroscope and motic software.results: our results indicated that the site of action of c-morphine was possibly located on the blood plexus of the fetal portion of the placenta. in addition, oral morphineconsumptionwasshowntoinhibitfetalandmaternalplacentaldevelopmentintheexperimental groups.14conclusion: we conclude that morphine’s effectiveness on the reduction of embryo growth and development may be via its effects on the blood plexus of the fetal section of the placenta. 14th and14th