Biểu hiện và Phân bố của Các Thụ thể Glucocorticoid trong Vỏ Thượng Thận Thai Nghé: Ảnh hưởng của Tình Trạng Thiếu Oxy Dài Hạn

Reproductive Sciences - Tập 15 - Trang 517-528 - 2008
Brandon Root1, Jenna Abrassart1, Dean A. Myers2, Tshepo Monau3, Charles A. Ducsay3
1University of Redlands, Redlands, USA
2Department of Obstetrics/Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, USA
3Center for Perinatal Biology, Loma Linda University, School of Medicine, Loma Linda, USA

Tóm tắt

Nghiên cứu này nhằm xác định xem tình trạng thiếu oxy dài hạn (LTH) có làm thay đổi sự biểu hiện của thụ thể glucocorticoid (GR) trong vỏ thượng thận thai nghé hay không. Các con cừu cái được duy trì ở độ cao 3820 m từ khoảng 30 đến 138 đến 140 ngày thai kỳ, và các thượng thận thai nhi được thu thập. Phân tích Western cho thấy có hai isoform GR-α khoảng 94-kDa và một dạng có trọng lượng phân tử thấp hơn (45 kDa). Xu hướng giảm trong tỷ lệ các băng 94-kDa / 45-kDa sau LTH cho thấy sự gia tăng trong sự tái tạo của GR. Kỹ thuật nhuộm miễn dịch mô học cho thấy sự nhuộm GR dày đặc ở vùng glomerulosa với sự nhuộm tối thiểu ở vùng fasciculata trong nhóm kiểm soát, trong khi sự nhuộm dày đặc được quan sát thấy trên toàn bộ vỏ trong tình trạng LTH. Phân tích Western và phản ứng chuỗi polymerase sao chép ngược xác nhận rằng isoform GR-β không có mặt hoặc được biểu hiện ở mức cực kỳ thấp trong thượng thận thai nhi, vùng hạ đồi, tuyến yên và nhau thai. Những dữ liệu này chỉ ra rằng LTH đã làm thay đổi chức năng của GR-α trong vỏ thượng thận thai nhi và gợi ý rằng GR-β không được biểu hiện ở cừu.

Từ khóa

#thụ thể glucocorticoid #thiếu oxy dài hạn #thượng thận thai nhi #GR-α #GR-β

Tài liệu tham khảo

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