Smith G W, Juengel J L, Mclntush E W, Youngquist R S, Garverick H A, Smith M F
Department of Animal Sciences, University of Missouri-Columbia, MO 65211, USA.
Domest Anim Endocrinol. 1996 Mar;13(2):151-60. doi: 10.1016/0739-7240(95)00065-8.
Tissue inhibitors of metalloproteinases 1 and 2 (TIMP-1 and TIMP-2) are important regulators of extracellular matrix remodeling and also possess growth factor activity. The objective of these studies was to characterize TIMP-1 and TIMP-2 mRNA expression by bovine periovulatory follicles/ corpora hemorrhagica (Experiment 1) and luteal tissue (Experiment 2). In Experiment 1, beef heifers (n = 27) were ovariectomized at-16 (n = 6), 0 (n = 5), 8 (n = 3), 16 (n = 4), 24 (n = 4), or 48 (n = 5) hr relative to a gonadotropin-releasing hormone induced gonadotropin surge (40 hr after prostaglandin F2 alpha-induced luteolysis). Total cellular RNA was isolated from the large steroidogenically active follicle or corpus hemorrhagicum obtained from each animal, and the expression of TIMP-1 and TIMP-2 mRNA was subsequently examined by northern and dot blot analysis. The expression of TIMP-1 or TIMP-2 mRNa did not differ in preovulatory follicles collected at -16 vs. 0 hr. Concentrations of both TIMP-1 and TIMP-2 mRNA (picograms per microgram of tissue DNA) were increased (P < 0.05) at 8 hr postgonadotropin surge, had declined to presurge levels by 24 hr (P < 0.05), and were increased (P < 0.05) in corpora hemorrhagica collected at 48 hr after a gonadotropin surge. In Experiment 2, corpora lutea were collected from beef heifers on Days 4, 10, 15 (n = 4 each), or 19 (n = 3) postestrus (Day 0 = estrus). Concentrations of TIMP-1 mRNA (picograms per microgram of tissue DNA) were greater in corpora lutea collected on Day 4 (P < 0.05) vs. Day 10, 15, or 19. Concentrations of TIMP-2 mRNA increased (P < 0.05) from Day 4 to 15 and decreased (P < 0.05) by Day 19. We conclude that: 1) during the periovulatory period, the ontogenies of TIMP-1 and TIMP-2 mRNA expression are similar, whereas 2) during luteal phase, TIMP-1 mRNA expression is maximal during the early luteal phase, whereas concentrations of TIMP-2 mRNA peak during the midluteal phase. TIMP-1 and TIMP-2 may play important roles in the regulation of extracellular matrix remodeling during the periovulatory period and the subsequent luteal phase.
金属蛋白酶组织抑制剂1和2（TIMP - 1和TIMP - 2）是细胞外基质重塑的重要调节因子，并且还具有生长因子活性。这些研究的目的是表征牛排卵前卵泡/出血性黄体（实验1）和黄体组织（实验2）中TIMP - 1和TIMP - 2 mRNA的表达。在实验1中，相对于促性腺激素释放激素诱导的促性腺激素激增（前列腺素F2α诱导黄体溶解后40小时），在-16小时（n = 6）、0小时（n = 5）、8小时（n = 3）、16小时（n = 4）、24小时（n = 4）或48小时（n = 5）对27头小母牛进行卵巢切除。从每只动物获得的大的具有类固醇生成活性的卵泡或出血性黄体中分离总细胞RNA，随后通过Northern印迹和斑点印迹分析检测TIMP - 1和TIMP - 2 mRNA的表达。在-16小时与0小时收集的排卵前卵泡中，TIMP - 1或TIMP - 2 mRNA的表达没有差异。促性腺激素激增后8小时，TIMP - 1和TIMP - 2 mRNA的浓度（皮克/微克组织DNA）均升高（P <0.05），到24小时降至激增前水平（P <0.05），在促性腺激素激增后48小时收集的出血性黄体中浓度升高（P <0.05）。在实验2中，在发情后第4、10、15天（每组n = 4）或19天（n = 3）从母牛收集黄体。与第10、15或19天相比，在第4天收集的黄体中TIMP - 1 mRNA的浓度（皮克/微克组织DNA）更高（P <0.05）。TIMP - 2 mRNA的浓度从第4天到第15天升高（P <0.05），到第19天下降（P <0.05）。我们得出结论：1）在排卵周期中，TIMP - 1和TIMP - 2 mRNA表达的个体发生相似，而2）在黄体期，TIMP - 1 mRNA表达在黄体早期最大，而TIMP - 2 mRNA的浓度在黄体中期达到峰值。TIMP - 1和TIMP - 2可能在排卵周期及随后的黄体期细胞外基质重塑的调节中起重要作用。
