title: Pathways of incorporation of fatty acid into glycerolipids of the murine peripheral nervous system in vivo: alterations in the dysmyelinating mutant trembler mouse.
abstract: In vivo glycerolipid metabolism was studied in sciatic nerves of normal and Trembler mice. The results showed that two kinetically independent pathways were implicated in the labeling of diacylglycerophospholipids from [3H]palmitate: the Kennedy pathway and a 'direct acylation' pathway. In normal nerves, 45% of the glycerophospholipids were labeled, with a rate constant k3 = 3.9 x 10(-3) min-1, from phosphatidic acid and diacylglycerol intermediates, themselves formed with a rate constant of k1 = 0.24 min-1 from a free 3H-fatty acid pool, FFA1, that represents 45% of the total injected label. The remaining 55% of the glycerophospholipids were labeled from a kinetically distinct free 3H-fatty acid pool, FFA2, with a rate constant of k4 = 9.8 x 10(-2) min-1, via a process that does not implicate a detectably labeled metabolic intermediate ('direct acylation'). Glycerophospholipid labeling via the Kennedy pathway in the Trembler mouse sciatic nerves was reduced to 75% of the normal level, while labeling via the 'direct acylation' pathway was increased 1.4-fold. The values of the rate constants for free 3H-fatty acid utilisation (k1 and k4) were both increased about 2.5-fold, while that of glycerophospholipid formation from diacylglycerol (k3) was close to normal.
authors.affiliation: Department of Pathology, University of Oulu, Finland.
authors.forename: A M
authors.initials: AM
authors.lastname: Heape
authors.forename: J J
authors.initials: JJ
authors.lastname: Bessoule
authors.forename: F
authors.initials: F
authors.lastname: Boiron-Sargueil
authors.forename: C
authors.initials: C
authors.lastname: Cassagne
mesh_terms: D000818:Animals; D003711:Demyelinating Diseases / Q000235:genetics / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D005994:Glycerophosphates / Q000378:metabolism*; D007700:Kinetics; D051379:Mice; D008818:Mice, Neurologic Mutants; D017933:Peripheral Nervous System / Q000378:metabolism*; D012016:Reference Values
chemical_list: D005227:Fatty Acids; D005994:Glycerophosphates