Immunolocalization of tissue inhibitor of metalloproteinases-1 within ovine periovulatory follicular and luteal tissues.
In previous studies, tissue inhibitor of metalloproteinases (TIMP)-1 mRNA increased in follicular tissue after the preovulatory gonadotropin surge and was expressed in luteal tissue. However, the localization of TIMP-1 protein within ovine periovulatory follicular and luteal tissues is unknown. The objectives of the present study were to 1) localize TIMP-1 within follicles collected before and after a preovulatory gonadotropin surge and within Day 3 and Day 10 corpora lutea (CL), 2) determine whether TIMP-1 was colocalized to Day 10 luteal cells with oxytocin or TIMP-2, and 3) determine whether TIMP-1 was present within secretory granules of large luteal cells. Ovaries were removed from ewes before (presurge; n = 4) or 12-14 h after (postsurge; n = 5) an LHRH-induced gonadotropin surge (36 h following PGF2 alpha-induced luteolysis; objective 1). Additionally, ovaries containing CL were collected on Days 3 (n = 5; objective 1) and 10 (n = 4, 3, and 2 for objectives 1, 2, and 3, respectively). TIMP-1 immunoreactivity was observed within the granulosa cells of postsurge but not presurge follicles. On Days 3 and 10, TIMP-1 was localized within luteal tissue in a cell-specific manner. On Day 10, many of the cells that were immunopositive for TIMP-1 were judged to be large luteal cells on the basis of morphology (diameter > 22 microns; round nucleus) and colocalization with oxytocin and TIMP-2. Electron microscopy demonstrated that TIMP-1 was localized to secretory granules undergoing exocytosis from Day 10 large luteal cells. These data indicate that TIMP-1 is produced by granulosa cells following a gonadotropin surge and is packaged in secretory granules by large steroidogenic cells of the ovine CL.
McIntush
E W
EW
Department of Animal Sciences, University of Missouri, Columbia 65211, USA.
Pletz
J D
JD
Smith
G D
GD
Long
D K
DK
Sawyer
H R
HR
Smith
M F
MF
D000818:Animals; D003338:Corpus Luteum / Q000378:metabolism* / Q000648:ultrastructure; D005260:Female; D006023:Glycoproteins / Q000378:metabolism*; D007150:Immunohistochemistry; D008854:Microscopy, Electron; D006080:Ovarian Follicle / Q000378:metabolism* / Q000648:ultrastructure; D010121:Oxytocin / Q000378:metabolism; D011506:Proteins / Q000378:metabolism; D012756:Sheep; D019716:Tissue Inhibitor of Metalloproteinase-2; D019714:Tissue Inhibitor of Metalloproteinases
D006023:Glycoproteins; D011506:Proteins; D019714:Tissue Inhibitor of Metalloproteinases; D019716:Tissue Inhibitor of Metalloproteinase-2; D010121:Oxytocin