Metallothionein-1 Messenger RNA Transcription in Steroid-Secreting Cells of the Rat Ovary During the Periovulatory Period

• Published in: Biology of reproduction 2003-05, Vol.68 (5), p.1895-1902
• Main Authors: ESPEY, L. L, UJIOKA, T, OKAMURA, H, RICHARDS, J. S
• Format: Article
• Language: English
• Subjects: Abortifacient Agents - pharmacology; ADAM Proteins; ADAMTS1 Protein; Androstenols - pharmacology; Animals; Biological and medical sciences; Blotting, Northern; Corpus Luteum - metabolism; Cyclooxygenase Inhibitors - pharmacology; Dinoprostone - metabolism; Disintegrins - biosynthesis; DNA, Complementary - biosynthesis; DNA, Complementary - genetics; Female; Fundamental and applied biological sciences. Psychology; Hormone metabolism and regulation; In Situ Hybridization; Indomethacin - pharmacology; Mammalian female genital system; Metalloendopeptidases - biosynthesis; Metallothionein - biosynthesis; Ovarian Follicle - physiology; Ovary - cytology; Ovary - metabolism; Ovulation - physiology; Progesterone - metabolism; Rats; Rats, Wistar; RNA, Messenger - biosynthesis; Steroids - metabolism; Tissue Inhibitor of Metalloproteinase-1 - biosynthesis; Transcription, Genetic; Vertebrates: reproduction
• ISSN: 0006-3363; 1529-7268
• DOI: 10.1095/biolreprod.102.013557

An increase in metallothionein 1 (MT-1) mRNA was detected in the ovaries of immature Wistar rats that were primed with s.c. injection of 10 IU eCG followed 48 h later by 10 IU hCG s.c. to initiate the ovulatory process. Ovarian RNA was extracted at 0, 2, 4, 8, 12, 24, 72, 144, and 288 h after the primed animals were injected with hCG. These extracts were used for reverse transcription polymerase chain reaction (RT-PCR) differential display and Northern analyses that yielded complementary gene fragments for MT-1. Expression of MT-1 mRNA increased significantly by 24 h after hCG treatment and reached a peak at 144 h after hCG. In contrast, a disintegrin and metalloproteinase with thrombospondin motifs and a tissue inhibitor of metalloproteinase 1, which were also detected by the RT-PCR differential display procedure, reached a peak at 12 h after hCG and returned to control levels in the ovaries by 72 h after hCG. In situ hybridization indicated that most of the MT-1 mRNA was expressed in the vicinity of the theca interna of preovulatory follicles and in the lutein granulosa of postovulatory follicles. Thus, MT-1 mRNA expression is primarily in the vicinity of steroid-secreting areas of the ovary. The substantial increase in MT-1 mRNA expression might be important in protecting the ovarian tissues from oxidative stress generated by ovarian inflammatory events during the ovulatory process and luteinization.