BOR - Papers in Press, published online ahead of print
October 14, 2002.
Biol Reprod 2002, 10.1095/biolreprod.102.006510
BIOLOGY OF REPRODUCTION 68, 140150 (2003)
DOI: 10.1095/biolreprod.102.006510
© 2003 by the Society for the Study of Reproduction, Inc.
Sertoli Cells in the Boar Testis: Changes During Development and Compensatory Hypertrophy after Hemicastration at Different Ages1
D.D. Lunstra2,a,
T.H. Wisea, and
J.J. Forda
a USDA, ARS, R.L. Hruska U.S. Meat Animal Research Center, Reproduction Research Unit, Clay Center, Nebraska 68933-0166
Changes in Sertoli cell numbers and testicular structure during normal development and compensatory hypertrophy were assessed in crossbred Meishan x White Composite males. Boars were assigned at birth to unilateral castration at 1, 10, 56, or 112 days or to remain as intact controls through 220 days. The first testes removed were compared to assess testicular development. At 220 days, testicular structure was evaluated in boars representing the 25% with the largest (Lg) testis and the 25% with the smallest (Sm) testis in each treatment group. The number of Sertoli cells per testis reached a maximum by Day 56 in Sm testis but not until Day 112 in Lg testis boars, indicating a longer duration of Sertoli cell proliferation in Lg testis boars. Unilateral castration of Lg testis boars on Days 1, 10, 56, and 112 caused the weight of the remaining testis to hypertrophy by 149%, 135%, 119%, and 120%, respectively, and total sperm production to increase to 127%, 128%, 97%, and 106%, respectively. However, Sertoli cell numbers changed little in hemicastrate boars. In Lg testis boars, compensatory hypertrophy primarily involved proliferation of Leydig cells and expansion of existing Sertoli cells with little increase in Sertoli cell numbers, but in Sm testis boars, it involved expansion of existing Leydig and Sertoli cells without increase in cell numbers. These results indicate that Lg and Sm testis boars display intriguing differences during both development and compensatory hypertrophy, and they identify a unique animal model for further studies of factors that program and control Sertoli cell proliferation.
1 Mention of trade names is necessary to report factually on available data. However, the USDA neither guarantees nor warrants the standard of the product, and the use of the same by USDA implies no approval of the product to the exclusion of others that may also be suitable.
2 Correspondence: D.D. Lunstra, Reproduction Research Unit, P.O. Box 166, State Spur 18D West, Clay Center, NE 68933. FAX: 402 762 4382; lunstra{at}email.marc.usda.gov
Copyright © 2003 by the Society for the Study of Reproduction.