
%0 Journal Article
%A Winnall, W. 
%A Muir, J. 
%A Hirst, J. 
%A Hedger, M. 
%T 245. Characterisation of prostaglandin production in the normal and inflamed rat testis
%J Reproduction, Fertility and Development
%D 2004/08/25
%V 16
%N 9
%P 245-245
%K 
%R https://doi.org/10.1071/SRB04ABS245
%U https://www.publish.csiro.au/paper/SRB04ABS245 
%X Prostaglandins E2 (PGE2) and F2&#945; (PGF2&#945;) play a role in Leydig cell function and in suppression of macrophage inflammatory functions. We predict that PGs also may play a role in interstitial fluid (IF) formation in the testis. Prostaglandin synthesis involves one of two distinct forms of cyclooxygenase (COX): constitutively expressed COX-1 and inducible COX-2. We recently demonstrated expression of both enzymes in macrophages, somatic and germ cells of the adult rat testis, and that COX-2 may the more important form in this organ. Adult male Sprague-Dawley rats were maintained on normal feed or 0.15% celebrex, a specific COX-2 inhibitor, for 5 weeks. Rats were subsequently treated with saline, or lipopolysaccharide (LPS&#x003B; 0.1 mg/kg or 5 mg/kg), 6 h prior to collection of tissues. PGE2 was measured by RIA in medium of cultured testis fragments and testicular cells from normal rats (± 10 &#956;g/mL LPS, 24 h, 37ºC), and in testicular interstitial fluid. PGE2 was constitutively produced by whole testis, Sertoli cells, Leydig cells and round spermatids, but not by resting macrophages or pachytene spermatocytes in culture. Stimulation with LPS upregulated PGE2 in macrophage cultures, but not in other cells or whole testis. Normal PGE2 levels in IF were 16&#8211;20 ng/mL&#x003B; levels were not altered by low-dose LPS, but were reduced by high-dose LPS. Celebrex caused a reduction in IF PGE2 levels in both the normal and low-dose groups, but not in the high-dose group. Celebrex elevated IF volume (25&#8211;50%) in all groups. Our experiments show cell-type specific regulation of PGE2 production in the rat testis, and predict a role for COX-2 elicited PGs in the IF regulation and in post-meiotic cell function. Paradoxically, low-level inflammation does not alter testicular PGE2 levels, as somatic and germ cells, which do not respond to LPS, appear to contribute most to the local levels of PGE2. 
