title: [A thermodynamic study on bovine spermatozoa by microcalorimetry after Percoll density-gradient centrifugation - experimental probe of its utility in andrology].
abstract: OBJECTIVE
  Microcalorimetric measurements can be used for recording exothermic or endothermic summation effects of a great variety of biological processes. The aim of the present study was to examine the usefullness of the microcalorimetry method to characterise the biological activity of spermatozoa.
  
  
  METHODS
  The heat flow of bovine fresh sperm as well as cryosperm samples were measured after Percoll density-gradient centrifugation in a 4-channel microcalorimeter. Various calibration times, volumes of samples and sperm concentrations were tested and analysed. Sperm concentration was recorded by a computer-assisted, computer-aided software system method (CASA).
  
  
  RESULTS
  Using a calibration time of 15 minutes, the heat signal of the fresh and cryosperm samples showed a characteristic peak after 39.5 min and 38.1 min (mean), respectively, with a significant correlation to sample volume and sperm concentration (p < 0.05). For obtaining the best results, a sample volume of 1 ml and a sperm concentration of more than 50 x 10 (6)/mL was used.
  
  
  CONCLUSIONS
  With microcalorimetric measurements the biological activity of spermatozoa could be recorded for reproducible results, thus opening the way to an automatised ejaculate analysis in the future. More investigations are necessary to correlate microcalorimetric parameters with semen function.
authors.affiliation: Klinik für Urologie und Kinderurologie, Klinikum Bayreuth GmbH, Bayreuth. claus.fischer@chiru.med.uni-giessen.de
authors.forename: C
authors.initials: C
authors.lastname: Fischer
authors.forename: V
authors.initials: V
authors.lastname: Scherfer-Brähler
authors.forename: F
authors.initials: F
authors.lastname: Müller-Schlösser
authors.forename: I
authors.initials: I
authors.lastname: Schröder-Printzen
authors.forename: W
authors.initials: W
authors.lastname: Weidner
mesh_terms: D000818:Animals; D002152:Calorimetry, Differential Scanning / Q000379:methods*; D002417:Cattle; D002470:Cell Survival / Q000502:physiology*; D002499:Centrifugation, Density Gradient / Q000379:methods*; D008297:Male; D012815:Signal Processing, Computer-Assisted; D012984:Software; D013076:Sperm Count; D013081:Sperm Motility / Q000502:physiology; D013094:Spermatozoa / Q000166:cytology*