Developmental consequences of intra‐uterine exposure to cannabinoids: impact on the ventilatory system of newborns rats

Abstract

The endocannabinoid system is already present in the central nervous system in the early stages of embryonic development, including in areas responsible for respiratory control. Cannabis sativa (marijuana) is the illicit drug most commonly used during pregnancy. However, the relationship between marijuana use and ventilatory problems in the offspring is uncertain. Therefore, the present study evaluated the effects of exposure to cannabinoids during the gestational period on the respiratory control system in P6–7 and P12–13 male rats. To this end, osmotic pumps were implanted subcutaneously in pregnant female rats at embryonic day 0 and delivered vehicle or CB1 receptor agonist (WIN55,212–2, 0.5 mg/Kg/day) for 21 days. Ventilation (VE) of newborn was recorded during normocapnia and hypercapnia (7% CO2), as well as the O2 consumption (VO2). Our data showed a 15% increase of hypercapnic ventilatory response in P6–7 WIN‐treated animals during 7% CO2 due to a higher respiratory frequency and an increase of the respiratory equivalent. For P12–13 rats, WIN‐treated animals showed a hyperventilation (VE/VO2) in basal conditions and an increase hypercapnic ventilatory response (~20%) due to an increase in both tidal volume and respiratory frequency. No difference in VO2 was observed between groups for both ages. Our results suggest that a chronic and over activation of endocannabinoid system during gestation alters basal ventilation and CO2‐drive to breathing during neonatal period.Support or Funding InformationSao Paulo Research Foundation (FAPESP) and National Council for Scientific and Technological Development (CNPq)This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.