Abstract
Rationale Despite a long history of use in synaptic physiology, the lobster has been a neglected model for behavioral pharmacology. A restauranteur proposed that exposing lobster to cannabis smoke reduces anxiety and pain during the cooking process. It is unknown if lobster gill respiration in air would result in significant Δ9-tetrahydrocannabinol (THC) uptake and whether this would have any detectable behavioral effects.
Objective The primary goal was to determine tissue THC levels in the lobster after exposure to THC vapor. Secondary goals were to determine if THC vapor altered locomotor behavior or nociception.
Methods Tissue samples were collected from muscle, brain and hemolymph of Homarus americanus (N=3 per group) following 30 or 60 minutes of exposure to vapor generated by an e-cigarette device using THC (100 mg/mL in a propylene glycol vehicle). Separate experiments assessed locomotor behavior and hot water nociceptive responses following THC vapor exposure.
Results THC vapor produced duration-related THC levels in all tissues examined. Locomotor activity was decreased (distance, speed, time-mobile) by 30 min inhalation of THC. Lobsters exhibit a temperature-dependent withdrawal response to immersion of tail, antennae or claws in warm water; this is novel evidence of thermal nociception for this species. THC exposure for 60 minutes had only marginal effect on nociception under the conditions assessed.
Conclusions Vapor exposure of lobsters, using an e-cigarette based model, produces dose-dependent THC levels in all tissues and reduces locomotor activity. Hot water nociception is temperature dependent in the lobster, but no clear effects of THC inhalation were confirmed.
Competing Interest Statement
La Jolla Alcohol Research, Inc (LJARI) engages in commercial development of vapor inhalation techniques and equipment, including with support from the R44 DA041967 SBIR grant. LJARI donated funds for some of the lobster purchases but was not directly involved in the design of the experiments, analysis and interpretation of data or the decision to submit the study for publication.
