Figure 4.

Chronic exposure of WIN 55 in endometriosis (EM) induced mice attenuates lesion growth and vascularization. Immunocompetent C57Bl/6N mice were induced with EM and treated with 14 doses of WIN 55 (1mg/kg i.p) before euthanasia on day 28. Lesions recovered from vehicle, and WIN 55 treated mice were analyzed for hallmarks of EM, such as proliferation and angiogenesis. Representative IHC images of Ki-67 (A,B) (marker of proliferation), CD31 (D,E) (marker of vasculature), Caspase-3 (G,H) (marker of apoptosis), CB1 (J,K), and CB2 (M,N). Lesions from mice that were subjected to chronic exposure of WIN 55 showed a significant reduction in tissue proliferation (C) and angiogenesis (F), while caspase activity was significantly increased (I), which indicates heightened apoptosis. Cannabinoid receptors CB1 (L) and CB2 (O) also showed reduced expression in these lesions compared with the group treated with vehicle. The black box within the IHC images represents the analysis used in this study, where yellow, orange, and red denotes weak, mild, and strong staining, respectively. Scale bar 100 μm. Non-parametric unpaired student's t-test. *P < 0.05 **P < 0.01 ***P < 0.001.