Epithelium 蛋白质的吸收 Lumen Interstitial space Proteins One of many brush-border peptidases A Action of luminal, brush border, and cytosolic Gastric and peptidases(三个部位的肽酶). Pepsin from pancreatIc the stomach and the five pancreatic proteases peptidases Tripeptidase AA hydrolyze proteins-both dietary and (AA endogenous-to single amino acids, aA, or to oligopeptides, (AA). These reactions occur in (AA)3 AA the lumen of the stomach or small intestine Oligo Various peptidases at the brush borders of peptides H AA 合仓 enterocytes then progressively hydrolyze (AA)n oligopeptides to amino acids. the amino acids PepT1 are directly taken up by any of several transporters(A被转运体直接摄取).The Amino enterocyte directly absorbs some of the small acids (AA) AA oligopeptides through the action of the h Proteins /oligopeptide cotransporter(PepT1).These (AA) small peptides are digested to amino acids by AA|→ peptidases in the cytoplasm of the enterocyte (也可直接吸收部分寡肽但在细胞内分解为 Dipeptidase AA). Several Na-independent amino acid transporters move amino acids out of the cell across the basolateral membrane(基侧膜上 的非Na依赖性AA转运体) AA+AA A→分 One of many AA transporters蛋白质的吸收 Proteins Action of luminal, brush border, and cytosolic peptidases（三个部位的肽酶）. Pepsin from the stomach and the five pancreatic proteases hydrolyze proteins—both dietary and endogenous—to single amino acids, AA, or to oligopeptides, (AA)n . These reactions occur in the lumen of the stomach or small intestine. Various peptidases at the brush borders of enterocytes then progressively hydrolyze oligopeptides to amino acids. The amino acids are directly taken up by any of several transporters（AA被转运体直接摄取）. The enterocyte directly absorbs some of the small oligopeptides through the action of the H /oligopeptide cotransporter (PepT1). These small peptides are digested to amino acids by peptidases in the cytoplasm of the enterocyte （也可直接吸收部分寡肽但在细胞内分解为 AA）. Several Na -independent amino acid transporters move amino acids out of the cell across the basolateral membrane（基侧膜上 的非Na依赖性AA转运体）