Cremophor

This study was approved by the Temple University Animal Care and Use Committee and was conducted in a manner that does not inflict unnecessary pain or discomfort upon the animal, as outlined by the United States Public Health Service Policy on Humane Care and Use of Laboratory Animals and the Guide for the Care and Use of Laboratory Animals. Twenty-six male and 120 female C57Bl/6 mice (ACE Animals, Boyertown, PA) were group housed under a reverse 12-hour light/dark cycle with ad libitum access to food and water. Mice were treated with paclitaxel (1.0 to 8.0 mg/kg IP), Cremophor vehicle (ETOH: Cremophor: saline in a 1:1:18 ratio), or saline on a standard dosing regimen of days 1, 3, 5, and 7. CBD-treated mice (5.0 or 10.0 mg/kg IP) or controls (Cremophor vehicle) were also injected once daily on days 1 to 14. The acetone drop test^{4 (link)} and Von Frey filament assay⁵ were used to assess cold and mechanical allodynia, respectively. Baseline responses in each assay were determined on separate days before administration of paclitaxel. Subsequent behavioral testing was performed every 3 to 10 days after the start of drug dosing. Briefly, mice were placed inside ventilated polycarbonate chambers on an aluminum mesh table. For assessment of cold allodynia, 0.05 mL of acetone was projected via a needle and syringe onto the plantar surface of the right hindpaw, and time spent attending to the paw was recorded for 60 seconds. For assessment of mechanical allodynia, von Frey filaments ranging from 0.16 to 6 g bending force were applied to the plantar skin of the right hindpaw, and each application was held for 6 seconds, using the up–down method to determine threshold sensitivity. Two-way (GraphPad Prism 4.0) analysis of variance (ANOVA) with the factors of Treatment and Time were used to examine the effect of paclitaxel and CBD treatment within a sex. Three-way (PASW Statistics 18.0) ANOVAs with factors of Treatment, Time, and Sex were used to examine the effect of paclitaxel between sexes.