title: The testicular descent in the rat: a scanning electron microscopic study.
abstract: OBJECTIVE
  Numerous researchers studied the morphology of testicular descent including the possible function of gubernaculum. However, a clear illustration of this process is still missing. The aim of this study was to illustrate testicular descent using scanning electron microscopy (SEM) in a rat model.
  
  
  METHODS
  The abdomen of rat fetuses between gestational day (E) 15 and E 22 and newborns at postnatal day (D) 0 and D 1.5 was opened by microsurgery. Standard preparation for SEM was carried out. The position of the testis and gubernaculum testis was documented.
  
  
  RESULTS
  The gubernaculum was obvious in male rat embryos at E 17.5. In a first phase (E 16-E 21) the testis moved from cranio-lateral and dorsal to caudo-medial and ventral, while clear signs of an active role of the gubernaculum were missing. In a second phase (E 22-D 1.5) the processus vaginalis peritonei (PVP) developed, while the conus of the gubernaculum disappeared, after which, the testis moved out of the abdominal cavity and entered the PVP.
  
  
  CONCLUSIONS
  In our study, we could not specify the role of gubernaculum for testicular descent. However, our data showed that the testis lay intraperitoneal throughout the descensus testis.
authors.affiliation: Department of Pediatric Surgery, Goethe University of Frankfurt, Theodor-Stern-Kai 7, 60590 Frankfurt, Germany. henning.fiegel@kgu.de
authors.forename: Henning C
authors.initials: HC
authors.lastname: Fiegel
authors.forename: Udo
authors.initials: U
authors.lastname: Rolle
authors.forename: Roman
authors.initials: R
authors.lastname: Metzger
authors.forename: Christian
authors.initials: C
authors.lastname: Geyer
authors.forename: Holger
authors.initials: H
authors.lastname: Till
authors.forename: Dietrich
authors.initials: D
authors.lastname: Kluth
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D004622:Embryo, Mammalian; D005333:Fetus; D008297:Male; D008855:Microscopy, Electron, Scanning; D023421:Models, Animal; D051381:Rats; D017207:Rats, Sprague-Dawley; D013737:Testis / Q000502:physiology* / Q000648:ultrastructure*
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