Co-Authors:
Silanikove, N., Biology of Lactation Laboratory, Institute of Animal Science, Agricultural Research Organization, P.O. Box 6, Bet Dagan 50250, Israel
Shapiro, F., Biology of Lactation Laboratory, Institute of Animal Science, Agricultural Research Organization, P.O. Box 6, Bet Dagan 50250, Israel
Merin, U., Department of Food Quality and Safety, Institute of Postharvest and Food Sciences, Volcani Center, P.O. Box. 6, Bet Dagan 50250, Israel
Leitner, G., National Mastitis Reference Center, Kimron Veterinary Institute, P.O. Box 12, Bet Dagan 50250, Israel
Abstract:
The aims of this study were to test the assumption that tissue-type plasminogen activator (t-PA) and plasminogen (PG) are closely associated with the casein micelle and form a functional complex that rules casein degradation. This assumption was essentially verified for bovine milk under conditions wherein the plasmin system was activated by treatment with casein hydrolysate. It was also shown that urokinase-type PA (u-PA), the second type of plasminogen activator present in milk, was not involved in casein degradation. In agreement with previous studies, we show that treatment with casein hydrolysate precipitously reduced mammary secretion, disrupted the tight junction integrity (increase in Na+ and decrease in K+ concentrations), induced hydrolysis of casein, and activated various elements of the innate and acquired immune system. In the present study, we have identified t-PA as the principal PA, which is responsible for the conversion of PG to plasmin. It was found that t-PA and plasminogen are present in freshly secreted milk (less than 10Â min from its secretion), suggesting that they are secreted as a complex by the mammary gland epithelial cells. Further research is needed to provide the direct evidence to verify this concept. Copyright © Proprietors of Journal of Dairy Research 2013.
תפריט נגישות
ניגודיות עדינה
מונוכרום
הדגשת קישורים
חסימת אנימציה
פונט קריא
סגור
איפוס הגדרות נגישות
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