Testosterone injection stimulates net protein synthesis but not tissue amino acid transport

Arny A. Ferrando, Kevin D. Tipton, David Doyle, Stuart M. Phillips, Joaquin Cortiella, Robert R. Wolfe

Research output: Contribution to journalArticle

202 Citations (Scopus)

Abstract

Testosterone administration (T) increases lean body mass and muscle protein synthesis. We investigated the effects of short-term T on leg muscle protein kinetics and transport of selected amino acids by use of a model based on arteriovenous sampling and muscle biopsy. Fractional synthesis (FSR) and breakdown (FBR) rates of skeletal muscle protein were also directly calculated. Seven healthy men were studied before and 5 days after intramuscular injection of 200 mg of testosterone enanthate. Protein synthesis increased twofold after injection (P < 0.05), whereas protein breakdown was unchanged. FSR and FBR calculations were in accordance, because FSR increased twofold (P < 0.05) without a concomitant change in FBR. Net balance between synthesis and breakdown became more positive with both methodologies (P < 0.05) and was not different from zero. T injection increased arteriovenous essential and nonessential nitrogen balance across the leg (P < 0.05) in the fasted state, without increasing amino acid transport. Thus T administration leads to an increased net protein synthesis and reutilization of intracellular amino acids in skeletal muscle.

Original languageEnglish (US)
JournalAmerican Journal of Physiology - Endocrinology and Metabolism
Volume275
Issue number5 38-5
StatePublished - 1998

Fingerprint

Muscle Proteins
Testosterone
Tissue
Amino Acids
Injections
Leg
Skeletal Muscle
Proteins
Intramuscular Injections
Protein Transport
Muscle
Nitrogen
Biopsy
Muscles
Sampling
Kinetics

Keywords

  • Amino nitrogen uptake
  • Fractional breakdown rate

ASJC Scopus subject areas

  • Physiology
  • Endocrinology
  • Biochemistry
  • Physiology (medical)

Cite this

Testosterone injection stimulates net protein synthesis but not tissue amino acid transport. / Ferrando, Arny A.; Tipton, Kevin D.; Doyle, David; Phillips, Stuart M.; Cortiella, Joaquin; Wolfe, Robert R.

In: American Journal of Physiology - Endocrinology and Metabolism, Vol. 275, No. 5 38-5, 1998.

Research output: Contribution to journalArticle

Ferrando, Arny A. ; Tipton, Kevin D. ; Doyle, David ; Phillips, Stuart M. ; Cortiella, Joaquin ; Wolfe, Robert R. / Testosterone injection stimulates net protein synthesis but not tissue amino acid transport. In: American Journal of Physiology - Endocrinology and Metabolism. 1998 ; Vol. 275, No. 5 38-5.
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