Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/45137
標題: Contribution of somatic cell-associated activation of plasminogen to caseinolysis within the goat mammary gland
作者: Weng, M.H.
陳洵一
Chang, C.J.
Chen, W.Y.
Chou, W.K.
Peh, H.C.
Huang, M.C.
Chen, M.T.
Nagahata, H.
黃木秋
張釵如
關鍵字: plasminogen activation system
caseinolysis
mammary involution
somatic
cell
bovine-milk
endogenous proteolysis
subclinical mastitis
urokinase
receptor
dairy-cows
dry period
involution
proteins
tissue
lactation
期刊/報告no:: Journal of Dairy Science, Volume 89, Issue 6, Page(s) 2025-2037.
摘要: Functional regression of the mammary gland is partly reflected by proteolysis of milk protein and tissue protein. The involvement of the plasminogen activation system in degradation of milk protein and mammary tissue damage has been demonstrated under inflammatory conditions. In this study, mammary secretion from 23 dairy goats primarily grouped as lactation (milking twice daily) or involution (milking once daily or less) was used to determine the ratio of gravity-precipitated casein to total milk protein (casein ratio) as an index of caseinolysis, and activities of components of plasminogen activation system as well as their expressions on somatic cells. Based on the casein ratio, lactation goats were subcategorized as very active (71.8 +/- 1.0%) or less active (29.9 +/- 1.0%) in mammary function; involution goats were subcategorized as gradual (21.7 +/- 1.0%) or acute (5.9 +/- 0.2%) involution. This result suggests that caseinolysis occurred during regular lactation as well as during involution. On the other hand, activities of components of the plasminogen activation system in mammary secretion were increased along with the decreasing casein ratio, in contrast to the similar activities of their counterparts in circulation throughout various mammary statuses. Correlation analysis between casein ratio and activities of plasminogen activation system of goat milk indicated a significant negative relationship for plasmin (r = -0.64), plasminogen (r = -0.69), and urokinase-type plasminogen activator (uPA; r = -0.78) during involution but not during lactation. As for the cellular components of plasminogen activation system, there was an increase in immunoreactivity on somatic cells toward both monoclonal antibodies of human uPA and human uPA receptor under involution conditions suggesting their upregulation relative to lactation condition. Collectively, these results suggest that plasminogen activation system within the mammary gland differentially contribute to milk caseinolysis along the various stages of goat lactation. Meanwhile, a somatic cell-mediated local elevation of plasmin activity may be committed to extensive caseinolysis during involution.
URI: http://hdl.handle.net/11455/45137
ISSN: 0022-0302
Appears in Collections:動物科學系

文件中的檔案:

取得全文請前往華藝線上圖書館



Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.