Journal of Lipid Research, Vol 26, 473-477, Copyright © 1985 by Lipid Research, Inc.
Inhibition of cerebroside synthesis in the brains of mice treated with L-cycloserine
KS Sundaram and M Lev
Subcutaneous injection of L-cycloserine resulted in a 28% reduction in
cerebroside levels in mouse brain but had no effect on the levels of
gangliosides. In contrast, intraperitoneal injection results in a reduction
of ganglioside as well as cerebroside + sulfatide levels. The route of
injection influenced the degree of 3-ketodihydrosphingosine synthase
inhibition. Intraperitoneal injection caused a rapid decrease in synthase
activity followed by recovery over 48 hr, whereas subcutaneous injection
resulted in no inhibition over this time; only after daily injection for a
week was synthase activity reduced 35%. One week following cessation of
L-cycloserine administration, enzyme activity had recovered, whereas the
cerebroside level continued to fall. All lipids and enzymes showed normal
levels 3 weeks post- cycloserine administration. L-[3H]serine incorporation
into glycolipids showed that cerebroside synthesis was most affected,
whereas sulfatide synthesis was less affected. One week after cessation of
cycloserine treatment, cerebroside synthesis was still severely inhibited,
whereas sulfatide levels were near normal. Two weeks after cessation of L-
cycloserine administration, synthesis of these glycolipids was similar to
that of controls.