Acute postnatal exposure to triethyltin in the rat: effects on specific protein composition of subcellular fractions from developing and adult brain
O'Callaghan, J.P.; Miller, D.B.; Reiter, L.W.
Journal of Pharmacology and Experimental Therapeutics 224(2): 466-472
1983
ISSN/ISBN: 0022-3565 PMID: 6822967 Document Number: 197175
The morphological maturation of the CNS is characterized by ontogenetic changes in proteins associated with specific developmental processes. The effects of acute postnatal administration of triethyltin (TET) on the ontogeny of proteins associated with myelinogenesis, synaptogenesis and synaptic junction formation were examined. Myelin, synaptic plasma membrane and synaptosomal cytosolic fractions were prepared from 13-, 22- and 66-day-old Long-Evans rats that had received either saline or TET (3.0 or 6.0 mg/kg i.p.) at 5 days of age. The specific protein composition of each fraction was evaluated by resolution of the fraction proteins on sodium dodecyl sulfate-polyacrylamide slab gels. The presence of marker phosphoproteins associated with each fraction was determined by 3 criteria: electrophoretic mobility; developmental profile; and autoradiography of incorporated phosphate. The specific protein and phosphoprotein content of each fraction was quantified by microdensitometry. The postnatal day 5 administration of TET produced a dose-related decrease in the concentration of myelin basic protein, a myelin-specific marker. This effect was large in magnitude (40-60% of control) and was observed in myelin fractions prepared from 13-, 22- and 66-day-old subjects. No changes in the protein or phosphoprotein content of other subcellular fractions were observed after the day 5 administration of TET. Acute postnatal administration of TET may interfere selectively with myelinogenesis.