G. Rosiepen et al., ESTIMATION OF THE DURATION OF THE CYCLE OF THE SEMINIFEROUS EPITHELIUM IN THE NONHUMAN PRIMATE MACACA-MULATTA USING THE 5-BROMODEOXYURIDINETECHNIQUE, Cell and tissue research, 288(2), 1997, pp. 365-369
A comparatively low yield of germ cells has been reported for the sper
matogenic process in primates. Kinetic studies of spermatogenesis and
the spermatogenic cycle are needed to investigate this phenomenon but
require the application of radioactively labelled compounds or it-radi
ation. We have therefore investigated the suitability of a non-radioac
tive approach, viz., administration of 5-bromodeoxyuridine, for the de
termination of the kinetics of the spermatogenic cycle in a non-human
primate, the rhesus monkey (Macaca mulatta). Four adult in-season anim
als received a bolus of 33 mg/kg 5-bromodeoxyuridine, one testis from
each monkey was removed 3 h later and the other testis after 10 days a
nd 11 h. Tissue was fixed in Bouin's solution and embedded in Paraplas
t. 5-Bromodeoxyuridine was localized by immunogold-silver staining wit
h a monoclonal antibody. PAS-hematoxylin counterstaining was used for
spermatogenic stage identification. At 3 h, the leptotene and zygotene
spermatocytes in stages VII-IX were the most advanced 5-bromodeoxyuri
dine-positive cells. At 10 days 11h, the label had advanced and pachyt
ene spermatocytes in stages VI-IX contained 5-bromodeoxyuridine. The d
uration of the spermatogenic cycle was 10.42+/-0.07 days (range: 10.25
-10.62 days). Peritubular cells and interstitial cells were rarely 5-b
romodeoxyuridine-positive, and Sertoli cells were consistently negativ
e for 5-bromodeoxyuridine. Importantly, our kinetic data closely resem
ble those obtained by means of the application of irradiation for this
macaque species. We conclude that administration of 5-bromodeoxyuridi
ne represents a non-radioactive reliable approach for studying kinetic
aspects of the spermatogenic process in primates.