Brian M Ross1, Pauline Ward, Iain Glen. 1. Ness Foundation, UHI Millennium Institute, Ness House, Dochfour Business Centre, Inverness, Dochgarroch IV3 8GY, UK. brian@ness-foundation.org.uk
Abstract
BACKGROUND: Recent evidence has suggested an important role for lipids in the etiology and treatment of depression. Methylnicotinate-induced vasodilation can be used to investigate lipid-dependent signalling mechanisms involving the phospholipase A2 (PLA2)/cyclooxygenase pathway, an important signalling system involved in the action of several neurotransmitters including serotonin. To investigate whether abnormalities in this signalling system may occur in depressive illness, we undertook a study of methylnicotinate response in unipolar depression (UD). METHODS: Methylnicotinate was applied to the forearm of 20 patients with depression and 38 age and sex-matched healthy volunteers (HV). The resulting erythema was assessed over a 15-min period. RESULTS: Methylnicotinate-induced erythema was reduced in subjects with depression compared to HV at 5 min after application, it returned to normal after 15 min. Thus, although the maximal response to methylnicotinate appears normal, patients with UD exhibit an apparently delayed response. LIMITATIONS: The major limitation is that all unipolar patients were medicated at the time of testing. CONCLUSIONS: Our results support the hypothesis that UD may be associated with abnormalities in lipid-associated signalling systems, and may provide insight into how lipid intake may modulate depressive symptoms.
BACKGROUND: Recent evidence has suggested an important role for lipids in the etiology and treatment of depression. Methylnicotinate-induced vasodilation can be used to investigate lipid-dependent signalling mechanisms involving the phospholipase A2 (PLA2)/cyclooxygenase pathway, an important signalling system involved in the action of several neurotransmitters including serotonin. To investigate whether abnormalities in this signalling system may occur in depressive illness, we undertook a study of methylnicotinate response in unipolar depression (UD). METHODS:Methylnicotinate was applied to the forearm of 20 patients with depression and 38 age and sex-matched healthy volunteers (HV). The resulting erythema was assessed over a 15-min period. RESULTS:Methylnicotinate-induced erythema was reduced in subjects with depression compared to HV at 5 min after application, it returned to normal after 15 min. Thus, although the maximal response to methylnicotinate appears normal, patients with UD exhibit an apparently delayed response. LIMITATIONS: The major limitation is that all unipolar patients were medicated at the time of testing. CONCLUSIONS: Our results support the hypothesis that UD may be associated with abnormalities in lipid-associated signalling systems, and may provide insight into how lipid intake may modulate depressive symptoms.
Authors: J Kornhuber; A Medlin; S Bleich; V Jendrossek; A W Henkel; J Wiltfang; E Gulbins Journal: J Neural Transm (Vienna) Date: 2005-11 Impact factor: 3.575