The short-term effects of testosterone on brain protein synthesis in 4-day-old rats: an electrophoretic study of proteins following intraventricular injection of [35S]methionine.
The short-term effects of administering testosterone propionate (TP) to 4-day female rats (androgenized females) on the synthesis of specific brain proteins were investigated. At various times after the intraperitoneal injection of TP or arachis oil, [35S]methionine was injected into the third ventricle and 1 h later proteins were extracted from the hypothalamus-preoptic area (H-POA) and analyzed by sodium dodecyl sulphate polyacrylamide gel electrophoresis. Changes in synthesis of two 13,000-14,000 mol. wt. proteins in the 4-day rat brain were detected, and these changes appeared to be specific for the H-POA. In addition, silver staining revealed a 50,000 mol. wt. protein which was present in the male and androgenized female H-POA but not in the oil-treated female H-POA. An incidental, but potentially important finding, was the synthesis of a 77,600 mol. wt. protein in the H-POA of one animal which had several seizures during the experiment. These results show that changes in the synthesis of specific proteins occur in the H-POA of neonatal female rats within 8 h of TP administration and support the hypothesis that hormone-induced changes in brain protein synthesis may be involved in sexual differentiation of the brain.
D000818:Animals; D000831:Animals, Newborn; D005260:Female; D007031:Hypothalamus / Q000378:metabolism*; D007276:Injections, Intraventricular; D008297:Male; D008715:Methionine / Q000378:metabolism; D008970:Molecular Weight; D009419:Nerve Tissue Proteins / Q000096:biosynthesis*; D011301:Preoptic Area / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D013739:Testosterone / Q000494:pharmacology*
D009419:Nerve Tissue Proteins; D013739:Testosterone; D008715:Methionine