Related Experiment Videos
Decreased protein synthesis during dry saturation diving
J M Conway1, J W Thorp, T P Stein
1United States Department of Agriculture, Agriculture Research Service, Beltsville Human Nutrition Research Center, Maryland 20705, USA.
Summary
Saturation diving significantly depresses protein synthesis by up to 50%, impacting whole-body and liver functions. This occurs despite divers maintaining a positive nitrogen balance, suggesting altered nitrogen metabolism.
Area of Science:
- Physiology
- Biochemistry
- Diving Medicine
Background:
- Metabolic changes during saturation dives are not fully understood.
- Protein metabolism is crucial for physiological function and adaptation.
Purpose of the Study:
- To investigate the effects of saturation diving on protein metabolism.
- To quantify changes in whole-body and liver protein synthesis.
Main Methods:
- 15N-glycine tracer method used in 11 Navy divers.
- Measurements taken during surface trials and dry saturation dives (0.56 MPa).
- Assessed whole-body protein synthesis via ammonia and urea endpoints.
- Estimated liver protein synthesis by 15N incorporation into fibrinogen.
Main Results:
- Whole-body protein synthesis decreased by 30-50% during saturation dives.
- 15N enrichment in fibrinogen glycine and hippurate precursors significantly decreased.
- Protein synthesis reduction occurred despite a positive nitrogen balance.
Conclusions:
- Dry saturation diving at 0.56 MPa significantly depresses protein synthesis.
- Altered liver nitrogen metabolism is suggested by reduced 15N incorporation into fibrinogen.
- Further research is needed to understand the underlying mechanisms.