Background: We had previously reported a decrease in agonist-induced platelet dense granule secretion in blood samples from male adolescents with and without Conduct Disorder (CD). In an augmented sample, we have now employed multivariate modeling to examine the simultaneous effects of CD and regular monthly alcohol and marijuana use on both the dense granule secretion and aggregation phases of agonist-induced platelet responses.
Methods: Blood samples were obtained from adolescents with and without a CD diagnosis. Platelet dense granule secretion and aggregation responses to a variety of agonists were examined in the laboratory.
Results: Significant multivariate interactions of CD status with regular marijuana use were found for responses to collagen, ADP alone, and ADP plus 0.2 microgram. of serotonin. Responses in platelets from youth with CD, but without regular marijuana use differed from other subjects. Multivariate main effects of marijuana use alone on platelet responses to arachidonic acid and ADP plus 1.0 microgram. of serotonin were found. No effects of alcohol use were found.
Conclusions: The results demonstrate an interaction between CD and the effects of chronic marijuana use for several agonists in this platelet model system, and further support the possibility of a variation in signal transduction mechanisms in CD.