m-Chlorophenylpiperazine challenge in borderline personality disorder: relationship of neuroendocrine response, behavioral response, and clinical measures.

We have previously found that a subgroup of patients with impulsive personality disorders respond to m-chlorophenylpiperazine (m-CPP) administration with a distinctive spacy/high behavioral reaction and with increased cortisol responses. In this report we analyzed the relationship between behavioral and neuroendocrine responses to m-CPP in an enlarged sample of patients with borderline personality disorder (BPD). We also assessed the association of behavioral and neuroendocrine responses with clinical symptoms and with m-CPP blood levels. We found that in BPD patients the presence of a spacy/high behavioral response was significantly associated with increased prolactin and cortisol responses to m-CPP. In BPD patients increased m-CPP levels were significantly associated with neuroendocrine hypersensitivity and with a spacy/high behavioral response, while in controls increased m-CPP levels were not significantly associated with neuroendocrine hypersensitivity but were significantly associated with dysphoric behavioral responses. Taken together with previous work on m-CPP in obsessive-compulsive disorder, these results are partially consistent with the hypothesis that compulsive and impulsive symptoms fall at opposite ends of a phenomenologic and neurobiologic spectrum.