PLATELET DENSE GRANULE SECRETION IN ADOLESCENTS WITH CONDUCT DISORDERAND SUBSTANCE-ABUSE - PRELIMINARY EVIDENCE FOR VARIATION IN SIGNAL-TRANSDUCTION

Platelet aggregation responses to agonists have been employed as perip heral indices of the physiological responsiveness and density of neuro transmitter receptors, and in investigations of membrane functioning i n psychopathological conditions. In particular, there are mechanistic similarities between neuronal secretory and receptor dynamics, and tho se involved in platelet dense granule secretion. Consequently, we have explored the platelet dense granule secretory responses to various ag onists in abstinent male adolescents who meet current psychiatric diag nostic criteria for Conduct Disorder and Psychoactive Substance Use Di sorder (CD+/PSUD+) in contrast to controls (CD-/PSUD-). The results sh owed a significant hyporesponsivity among experimental subjects to col lagen, thrombin, adenosine diphosphate (ADP), ADP plus 0.2 mu gm of se rotonin, and ADP plus 1.0 mu gm of serotonin. Only dense granule respo nses to arachidonic acid did not differentiate the groups. Taken toget her, the lack of agonist specificity suggests that a variation in sign al transduction mechanisms could account for the observed reduction in dense granule secretion among CD+/PSUD+ adolescents. Association betw een dense granule secretory responses and substance use behavior, and comorbid psychiatric conditions are also examined. (C) 1996 Society of Biological Psychiatry.