This experiment was conducted to study the role of oligopeptide transporter 2 in small peptides uptake and milk protein synthesis in bovine mammary gland. Different doses of Phe dipeptide (0 and 11.7 μg/mL）and DEPC (0, 0.01, 0.1, 0.5 and 1 mmol/L) were added to the culture medium of bovine mammary gland tissues. After incubated in the experimental medium, mammary tissues and medium were collected and used for gene expression and milk protein determination, respectively. The results showed that 1) Phe dipeptide increased oligopeptide transporter 2 and αs1-casein gene expression and milk protein quantity in the medium (P<0.05); 2) with increasing of DEPC dose, αs1-casein gene mRNA level (P<0.01) and synthesis of milk protein (P<0.05) were decreased; 3) treatment with 0.5 mmol/L DEPC significantly decreased αs1-casein gene expression (P<0.05) and synthesis of milk protein (P<0.01) in Phe dipeptide group, and synthesis of milk protein (P<0.05) in free Phe group, but had no effect on αs1-casein gene mRNA level (P>0.05) in free Phe group. These results indicate that Phe dipeptide can be used for synthesis of milk protein by bovine mammary gland while PepT2 may play an important role in small peptides uptake by bovine mammary gland.［Chinese Journal of Animal Nutrition, 2011, 23（8）：1303 -1308］
ZHOU Miaomiao,WU Yueming,LIU Hongyun,ZHAO Ke,LIU Jianxin
. Role of Oligopeptide Transporter 2 in Bovine Mammary Gland Phenylalanine Dipeptide Uptake[J]. Chinese Journal of Animal Nutrition, 2011
, 23(08)
: 1303
-1308
.
DOI: 10.3969/j.issn.1006-267x.2011.08.008
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