Physiochemical and pharmacological characterization of a Delta(9)-THC aerosol generated by a metered dose inhaler.
The goal of the present study was to formulate a Delta(9)-tetrahydrocannabinol (Delta(9)-THC) metered-dose inhaler (MDI) that can be used to provide a systemic dose of Delta(9)-THC via inhalation. Following physiochemical characterization and accelerated stability testing of the aerosol, mice were exposed to the aerosol and evaluated for pharmacological effects indicative of cannabinoid activity, including hypomotilìty, antinociception, catalepsy, and hypothermia. The fine particle dose of Delta(9)-THC was 0.22 +/- 0.03 mg (mean +/- S.D.) or 25% of the emitted dose and was not affected by accelerated stability testing. A 10-min exposure to aerosolized Delta(9)-THC elicited hypomotility, antinociception, catalepsy, and hypothermia. Additionally, Delta(9)-THC concentrations in blood and brain at the antinociceptive ED(50) dose were similar for both inhalation and intravenous routes of administration. Finally, pretreatment with the CB(1) receptor antagonist SR 141716A (10 mg/kg, i.p.) significantly antagonized all of the Delta(9)-THC-induced effects. These results indicate that an MDI is a viable method to deliver a systemic dose of Delta(9)-THC that elicits a full spectrum of cannabinoid pharmacological effects in mice that is mediated via a CB(1) receptor mechanism of action. Further development of a Delta(9)-THC MDI could provide an appropriate delivery device for the therapeutic use of cannabinoids, thereby reducing the need for medicinal marijuana.
Department of Pharmacology and Toxicology, Medical College of Virginia Campus, Virginia Commonwealth University, 410 N. 12th Street, PO Box 980613, Richmond, VA 23298, USA.
David M
DM
Wilson
Joanne
J
Peart
Billy R
BR
Martin
D Troy
DT
Bridgen
Peter R
PR
Byron
Aron H
AH
Lichtman
D000280:Administration, Inhalation; D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D013759:Dronabinol / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009043:Motor Activity / Q000187:drug effects / Q000502:physiology; D009330:Nebulizers and Vaporizers; D010147:Pain Measurement / Q000187:drug effects
C052413:delta(9-11)-tetrahydrocannabinol; D013759:Dronabinol