HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Benoit, A. M. Articles by Blake, C. A. Search for Related Content PubMed PubMed Citation Articles by Benoit, A. M. Articles by Blake, C. A.

---

ORIGINAL RESEARCH ARTICLE

Expression of Sperm Protein 22 (SP22) in the Rat Ovary During Different Reproductive States

Allison M. Benoit^*, Holly A. LaVoie^*, George L. McCoy and Charles A. Blake^*,1

^* Department of Cell and Developmental Biology and Anatomy, University of South Carolina School of Medicine, Columbia, South Carolina 29208; and Department of Biology, Chemistry and Environmental Health Science, Benedict College, Columbia, South Carolina 29204

To whom requests for reprints should be addressed at ¹ Department of CDBA, University of South Carolina School of Medicine, Columbia, SC 29208. E-mail: blake{at}med.sc.edu

Sperm protein 22 (SP22) is correlated with fertility in rats. It has been identified in testis and implicated in sperm-egg interaction, protection against oxidative stress, and androgen receptor function. SP22 is widespread in rat and human tissues but has not yet been reported in the ovary. Using reverse transcription polymerase chain reaction, we identified the presence of SP22 transcripts in the rat ovary. We assessed the cellular distribution of the SP22 protein by collecting ovaries from rats in each of the following groups: 30, 60, and 90 days old; Days 9.5, 14.5, 16.5, 18.5, and 20.5 of pregnancy; and Days 1, 2, 8, and 19 of lactation. Tissue sections were stained immunohistochemically for SP22, and some serial sections were stained for relaxin or cytochrome P450 cholesterol side-chain cleavage enzyme (SCC). Weak staining for SP22 was evident in some corpora lutea (CL) and some interstitial gland cells in nonpregnant adult rats. At Day 9.5 of pregnancy, SP22 was detected in all CL, but staining intensity was weak. Staining intensity for SP22 in CL increased from Day 9.5 to 20.5 of pregnancy but was low on postpartum Day 1 and thereafter. A similar temporal pattern of staining intensity in CL was observed for relaxin. Strong immunoreactivity for SCC was present in the CL throughout pregnancy, and the spatial distribution of staining for SP22 in CL and in some areas of ovarian stroma was similar to that for SCC. There was weak staining of some theca cells in some antral follicles of pregnant and early postpartum rats when heat-induced antigen retrieval was used. There was inconsistent staining of oocytes for SP22, particularly in 30-day-old rats. In summary, the expression of SP22 was most prevalent in the CL and increased during pregnancy.

Key Words: CAP1 • corpus luteum • cytochrome P450 cholesterol side-chain cleavage enzyme • DJ-1 • ovary • pregnancy • relaxin • sperm protein SP22