Cau 23: trinh bay cac thanh phan, tac dung cua dich mat va UDLS

Mat dc bai tiet duy nhat o gan, gan bai tiet mat qua 2 gd:

1. dau tien cac TB gan sx ra mat, goi la "mat dau" chua 1 lg lon acid mat, cholesterol va cac tp huu co khac. mat dc bai tiet vao cac tieu quan mat nam giua cac Tb gan trong cac be gan

2. den vach lien thuy cac tieu quan mat do vao cac ong tan, roi vao nhung ong mat co kick thuoc ngay cang lon hon, cuoi cung den ong gan va ong mat chu. Tu ong mat chu mat chay truc tiep vao ta trang or qua ong tui mat do vao tick tru trong tui mat.

Thanh phan mat o gan va o trong tui mat khac nhau

- thanh phan chu yeu cua mat la muoi mat, chiem khoang 50% cac chat hoa tan cua mat. Ngoai ra trong mat con co bilirubin, cholesterol, lecithin va cac chat dien giaI

- trong qua trinh co dac o tui mat, nc va cac chat dien giaI( tru Ca 2+) dc taI hap thu qua nmac tui mat. Muoi mat, cholesterol, lecithin dc co dac o tui mat.

*) tac dung: cac Tb gan sx ra khoang 0,5g muoi mat moi ngaytf cholesterol thuc an cung cap or dc tong hop trong cac TB gan. Cholesterol dc chuyen thanh acid cholic or acid chondesoxycholic voi lg = nhau. Cac acid nay gan voi glycin or taurin de tao thanh acid glycocholic va acid taurocholic. Muoi cua cac acid nay dc bai tiet vao mat

- muoi mat dong vtro qtrong trong tieu hoa va hap thu mo

- muoi mat giup cho qtrinh nhu tg hoa mo lam tang dien tick txuc cac hat cau mo voi enzym tieu hoa mo

- muoi mat giup cho su tieu hoa va hap thu cua cac acid beo, monglycerid, cholesterol va cac lipid khac o ruot non nho cac mixen muoi mat

- su thuy phan triglycerid thanh monoglycerid va cac acid la 1 qtrinh thuan nghich, neu monoglycerid va acid beo ko dc lay dI chung se ngan can su tieu hoa tiep tuc cua mo

- mixen muoi mat la nhung hat cau nho, dc cau tao tu 20 - 40 phan tu muoi mat. Moi ptu muoi mat gom 1 nhan sterol hoa tan trong mo va nhom cuc hoa tan trong nc. Cac nhan sterol cung voi cac ptu mo tap hop o trung tam cua hat mixin trong khi cac nhom cuc cua muoi mat quay ra phia ngoai tren be mat cua hat mixen

- cac nhom cuc tick dien am lam cho cac hat mixen hoa tan va giu dc dang on dinh trong trap. Trong qtrinh tieu hoa triglycerid, cac nhom ky nc phan tu monoglycerid va acid beo vua dc tao ra hoa tan ngay vao phan trung tam cua hat mixen do do lam giam nong do cua chung o vun lan can cac hat cau mo dc tieu hoa va ko anh huong den toc do thuy phan mo. Nhung hat mixen vc cac ptu monoglycerid va acid beo den diem ban cahi cua TB bmo ruot. o do monoglycerid va acid beo dc hap thu cac hat mixen quay tro lai long ruot de tiep tuc vc cac ptu mo khac

- neu ko co muoi mat trong ruot non, tren 40% lipid bi mat theo phan, BN bi roi loan chuyen hoa do bi mat mo.

*) UDLS