Suppression of constitutively expressed cyclooxygenase-2 in the epididymis of mice by nimesulide decreases sperm motility.
Significant levels of constitutive cyclooxygenase-2 (COX-2) are present in the male reproductive organs of rodents, especially in the vas deferens and epididymis. In the epididymis, the sperm storehouse, COX-2 is thought to play a vital role in altering the membrane lipids of sperm. The present study aims at localizing COX-2 in the epididymis and analyzing the effects of the preferential COX-2 inhibitor nimesulide. COX-2 protein activity was nearly equal to that of COX-1 in the cauda epididymis. Immunohistochemical studies showed an intense staining for COX-2 in the cauda epididymis but not in the caput epididymis. Nimesulide administration induced a significant reduction in both COX-2 staining intensity and protein activity, followed by an initial decline in total prostaglandin levels but a reversible increase upon sustained COX-2 suppression. Sperm numbers and vitality showed no significant change, but motility decreased and total and free serum testosterone levels mildly increased.
Balaji
Thotakura
T
Dept of Anatomy, Faculty of Medicine, Chettinad Hospital & Research Institute, Padur Village, Old Mahabalipuram Road, Kelambakkam, Chennai--603103.
Aruna
Subramanian
S
Ramanathan
Manickam
M
Srinivasan
Marimuthu
M
Menon
Venugopal Padmanabhan
VP
D000818:Animals; D051545:Cyclooxygenase 1 / Q000032:analysis; D051546:Cyclooxygenase 2 / Q000032:analysis / Q000378:metabolism; D052246:Cyclooxygenase 2 Inhibitors / Q000494:pharmacology*; D004822:Epididymis / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology / Q000648:ultrastructure; D005227:Fatty Acids / Q000032:analysis; D008297:Male; D051379:Mice; D011453:Prostaglandins / Q000032:analysis; D013081:Sperm Motility / Q000187:drug effects*; D013449:Sulfonamides / Q000494:pharmacology*; D013739:Testosterone / Q000097:blood
D052246:Cyclooxygenase 2 Inhibitors; D005227:Fatty Acids; D011453:Prostaglandins; D013449:Sulfonamides; D013739:Testosterone; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; C012655:nimesulide