Restoration of Leydig cells after repeated administration of ethane dimethanesulfonate in adult rats.
Adult male rats were repeatedly treated with ethane dimethanesulfonate (EDS), an agent known to destroy Leydig cells selectively. Following a second injection, changes in serum testosterone levels and histological and morphometric changes of Leydig cells showed the time course to be similar to those after the first treatment. The number and volume of Leydig cells markedly decreased at day 2, began to increase from day 7, and recovered to the values of the control rats at day 30, concomitant with the changes of serum testosterone levels. Cells in the interstitial tissue labeled with bromodeoxyuridine markedly increased in number at day 2, gradually decreased thereafter, and returned to the values of the controls at day 14. During this period, cells undergoing mitosis were seen, their type unable to be determined, but were presumed to be regenerating Leydig cells. Even 30 days following four treatments with intervals of 30 days each, serum testosterone levels were the same as those in the controls. Also the numerical and volume densities of Leydig cells and the volume of an average Leydig cell were the same as those of the controls. Mitosis was observed in mature Leydig cells at this period, if any. It appears that new Leydig cells began to proliferate by division earlier than 14 days after EDS, allowing that there were several stages of proliferation, and that the source of reappearing Leydig cells may not be a limited number of precursor cells, implying the presence of stem cells for Leydig cells.
Miyano
M
M
Department of Pathology, Osaka Medical College, Takatsuki, Japan.
Ito
Y
Y
Fujihira
S
S
Matsuo
T
T
Ueno
H
H
Mori
H
H
D000818:Animals; D001973:Bromodeoxyuridine / Q000032:analysis; D048429:Cell Size / Q000187:drug effects; D007985:Leydig Cells / Q000166:cytology* / Q000187:drug effects / Q000648:ultrastructure; D008297:Male; D008698:Mesylates / Q000008:administration & dosage / Q000494:pharmacology*; D008854:Microscopy, Electron; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D011916:Rats, Inbred F344; D013737:Testis / Q000033:anatomy & histology / Q000187:drug effects; D013739:Testosterone / Q000097:blood; D013997:Time Factors
D008698:Mesylates; D013739:Testosterone; C002994:ethylene dimethanesulfonate; D001973:Bromodeoxyuridine