Saturday, February 16, 2013
Auditorium/Exhibit Hall C (Hynes Convention Center)
Synthetic opiates are the most common anti-addictive prescription for opioid-addicted patients because of its euphoric effect and minimal side effects. An example is methadone hydrochloride, originally used as an analgesic and now as a treatment for narcotic addiction. Methadone has also been used recently to prevent the transmission of HIV from HIV-infected pregnant women into the developing fetus. Information is lacking, however, on the developmental effect of this methadone application. In this study, the effect of methadone on embryonic development was investigated using chick embryos as a model. Methadone was administered directly into the egg air sac of SPF white leghorn embryos daily during the gestation period using a 0.5cc insulin syringe. The following experimental treatments were established: control (saline vehicle only), 0.47, 1.00, and 1.47 µg/kg methadone in saline. At the end of the 20 day incubation period, chick liver, brain, and tibiotarsi were harvested for histological analysis. In addition, blood smears obtained by cardiac puncture were prepared for hematological analysis. The PCR method, applied to isolate a gene on the female W chromosome, indicated that the chick male/female ratio used in the experiment was 50/50. SPSS ANOVA was used to calculate differences between treatments in tissue and blood samples. Higher dosages exhibited an increase in the number of hemolyzed red blood cells and a decrease in white blood cell numbers, indicating a possible stress response and immune system suppression due to methadone administration. Comparing the low, medium and high dosages to controls, histological analysis of chick brains revealed evidence of reduced cellularity within the cerebral cortex regarding the astrocytes and glial cells. Spongiosis was present in both control and low dosage equally; however, significant reduction occurred in medium and high dosages. These pathological changes suggest that administration of synthetic opiates during pregnancy is harmful to the developing fetus.