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Subcutaneously injected stearic acid is taken up by the brain through the 'blood-brain barrier' and is incorporated into synaptosomal lipids (as well as into other brain compartments). Phospholipids are potent acceptors (choline phosphatides, ethanolamine phosphatides, serine phosphatides). Moreover a high level of radioactivity was found in non-esterified fatty acids.

Calcium levels have been determined in brain of C57Bl mice and in the Quaking dysmyelinating mutant during the myelination period. In control mice, calcium content per gram brain is maximum at 20 days, at the acme of myelination, and decreases thereafter to reach a plateau at 30 days. This variation does not occur in the mutant where the level is 50% lower than maximum in controls and stable at 15 days after birth. In control mice, the variation may be related to the level or to the qualitative variation of some glycolipids and proteolipids as it disappears in lipid extract after Folch wash.

Seven antigens specific to the nervous tissue were measured in both Jimpy and control mice. The D5 and the GFA protein, both components of the glia, are strongly increased in the mutant while the neuronal components 14-3-2, synaptin C1, D1, D2 and D3 are unchanged.

Noradrenergic cell bodies in the locus ceruleus of the convulsive mutant quaking mouse and the control of the same strain were visualized using histofluorescence and tyrosine hydroxylase-like immunoreactivity. Cell counts performed with the two techniques gave closely similar results within each strain, indicating a 50% increase in the number of noradrenergic neurons in the midportion of the mutants' locus ceruleus when compared to the controls. This result gives histological support to the increased noradrenergic neurotransmission previously described in the brain of this mutant. Thus, the abnormally high activity of the noradrenergic system appears to be a primary effect of the mutation, associated with the convulsions of this animal model of epilepsy.