Effect of delta 9-tetrahydrocannabinol on monoamine oxidase activity in bovine eye tissues, in vitro.

An investigation was undertaken to analyze the effects of delta 9-tetrahydrocannabinol (THC) on monoamine oxidase (MAO) activity from calf ocular tissues. Ciliary processes, retina, trabecular meshwork, choroid, and iris all demonstrated significant MAO activity in decreasing order of magnitude. THC in concentrations from 10(-8)M to 10(-12)M stimulated MAO activity in extracts from all five tissues, except for iris at 10(-8)M. Maximum stimulation of MAO activity occurred at the 1 x 10(-12)M level for all tissues. Retina, followed next by trabecular meshwork and then ciliary processes, exhibited the largest increase in MAO activity at 10(-12)M THC. This latter effect could possibly by related to the influence of THC on intraocular pressure.