Assessing the effects of prenatal cannabinoid consumption on fetal brain vasculature utilizing optical coherence angiography

There is a fundamental lack of understanding of the severe effects of cannabinoid consumption during pregnancy, especially on embryonic vasculature development. Our previous research has shown that prenatal cannabinoid exposure causes a decrease in cerebral blood flow, leading to neurodevelopmental and morphological alterations in the developing fetus. These include fetal growth restriction, learning disabilities, and memory impairment, among other negative outcomes. In this study, we assess the persistent effects of cannabinoid exposure on fetal brain vasculature in utero in a murine model. We analyzed the effects of different cannabinoid concentrations (0.0625 mg/kg, 0.25 mg/kg, and 1.0 mg/kg) on fetal brain vasculature. To assess the effects of persistent cannabinoid exposure, we administered the same cannabinoid concentration at multiple gestational days (GD12.5, 13.5, and 14.5) and imaged at GD14.5. To assess the acute effects, we administered a single dose of CP55,940 at GD14.5 and imaged immediately after. We utilized correlation mapping optical coherence angiography to image changes in fetal brain vasculature caused by exposure to cannabinoids at each dosage. Results show significant vasoconstriction of the main imaged blood vessel, which is located at the terminal anterior and middle cerebral arteries, irrigating the dorsolateral surface of the embryonic brain, for all three administered dosages. The difference in the primary blood vessel diameter before and after the final cannabinoid exposure at GD14.5 shows that the initial vasculature, when dosed at multiple stages, shows a significant effect in vasculature before the last dose, compared to the measurement before a single dose exposure. This contrasts with the acute dosing effects, which show a change in the blood vessel diameter, over the course of the 45 minutes of measurements. Overall, the multiple dosing and acute effects of cannabinoid consumption demonstrated a decrease in blood flow in the fetal brain.