Localization of stress protein-70 in ovine corpora lutea during prostaglandin-induced luteolysis.
Accumulation of heat shock (stress) protein-70 (HSP-70) was assessed in corpora lutea of sheep obtained after in vivo administration of a luteolytic dose of prostaglandin (PG) F2 alpha. A quantitative immunofluorescence technique was used to localize inducible HSP-70 production to specific cell-types. The number and intensity of immunostained large luteal cells increased within 2 h of injection of PGF2 alpha. A drop in luteal progesterone concentrations (functional regression) was not manifested until 4 h post-treatment. A dramatic increase in intensely-stained mononuclear leukocytes was observed in luteal tissues at 16 h, when glandular weights had begun to diminish (structural regression). Stress proteins could mediate intracellular protein processing and cell-surface autoimmune mechanisms underlying luteal regression.
McPherson
L A
LA
Department of Animal Science, University of Wyoming, Laramie 82071.
Van Kirk
E A
EA
Murdoch
W J
WJ
D000818:Animals; D003338:Corpus Luteum / Q000033:anatomy & histology / Q000187:drug effects / Q000502:physiology*; D015237:Dinoprost / Q000494:pharmacology*; D005260:Female; D005455:Fluorescent Antibody Technique; D006360:Heat-Shock Proteins / Q000378:metabolism*; D003341:Luteolysis / Q000187:drug effects / Q000502:physiology*; D009929:Organ Size; D011374:Progesterone / Q000378:metabolism; D012756:Sheep
D006360:Heat-Shock Proteins; D011374:Progesterone; D015237:Dinoprost