Reduced vasodilatory response to methylnicotinate in schizophrenia as assessed by laser Doppler flowmetry

The normal vasodilatory response to topically applied methylnicotinate has been reported to be absent or reduced in patients with schizophrenia, a finding thought to be related to aberrant phospholipid metabolism. Previous studies have however failed to measure vasodilation using a direct and objective method. In addition, it is unknown whether methylnicotinate insensitivity is specific to schizophrenia. To address these issues we compared the magnitude of methylnicotinate-induced vasodilation in chronically ill patients with schizophrenia (SCZ) (n=27) or bipolar disorder (BP) (n=26) to that in healthy controls (n=32). Blood flow was monitored using laser Doppler flowmetry. Vasodilatory response to 1 and 10 mM methyl nicotinate was markedly and significantly reduced in patients with schizophrenia compared to that in subjects with bipolar disorder and healthy controls. In conclusion, reduced methyl nicotinate response in schizophrenia has been demonstrated using an objective measure of vasodilation. Our data further support the potential utility of this measure as a diagnostic marker for schizophrenia.