The aim of this study was to test the hypothesis that Huntington's disease
is associated with impaired phospholipid-related signal transduction using
the niacin skin flush test. This is the first reported use of this test in
this patient group. Ile response to topical aqueous methyl nicotinate solut
ion was recorded at 5 min intervals over 20 min in six in-patients with adv
anced (stage III) Huntington's disease and in 14 age- and sex-matched norma
l individuals with no history of this or any other major neurological disor
der. The volumetric niacin response (VNR) (mean +/- S.E.M.) in the patients
with Huntington's disease, 16.3 +/- 2.6 mol s l(-1), was significantly low
er than the mean VNR of 28.3 +/- 2.1 mol s l(-1) in the control group (P =
0.004). These results are consistent with the conclusion that Huntington's
disease may be associated with an abnormality of neuronal membrane fatty ac
id metabolism, possibly as a consequence of an as yet unidentified action o
f huntingtin.