title: Energy economy of human uterine muscle strips under different in vitro conditions and its dependence on tissue redox potential.
abstract: OBJECTIVE
  To study the energy economy of human myometrium in vitro.
  
  
  METHODS
  Myometric biopsies were kept for 10 min or 4 h in a buffer solution at +4 degrees C before preparation into 'early' and 'late' strips, respectively. The strips were perifused at +37 degrees C for different periods of time. Adenylates, energy charge (EC), adenosine and NAD+ were determined in individual strips.
  
  
  RESULTS
  Mean EC and ATP values were low, the 'late' strips displaying 5% and 20% lower values than the 'early' strips, respectively. During perifusion the EC increased slightly, ADP decreased significantly and the strips began to contract. A correlation fitting a multiplicative function was evident between EC and NAD+ (r = 0.89, P < 0.001).
  
  
  CONCLUSIONS
  Human myometrium, being operative at an unusually low EC level, maintained its energy economizing and contractile functions in vitro for 4 h, displaying a tight relationship between EC and NAD+, suggestive of a compromised energy balance.
mesh_terms: D000244:Adenosine Diphosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000328:Adult; D004734:Energy Metabolism; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D007700:Kinetics; D009215:Myometrium / Q000378:metabolism*; D009243:NAD / Q000378:metabolism; D010084:Oxidation-Reduction; D011247:Pregnancy; D014590:Uterine Contraction / Q000502:physiology*
chemical_list: D009243:NAD; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate