Bilateral adrenalectomy: factors affecting hepatic protein synthesis following a single tube-feeding of tryptophan.

Effect of tryptophan force-feeding to well-fed adrenalectomized rats on the ability of liver cell sap and initiation factors to support protein synthesis in vitro was investigated. 5 h after tryptophan force-feeding, the capacity of liver cell sap, pH 5 enzyme and pH 5 supernatant to support protein synthesis was greatly increased. The capacity of cell sap to support charging of tRNA with either (14C)-leucine or (14C)-phenylalanine was increased following a dose of tryptophan. Initiation factors prepared from tryptophan-fed adrenalectomized rats stimulated polyuridylic-acid-directed polyphenylalanine synthesis to a greater extent than those from livers of water-fed adrenalectomized controls.