Insulin Transport

Figure 5 Schematic representation of a chemical valve, (a) swollen poly(acrylic acid) blocks insulin transport, (b) glucose oxidation causes a decrease in pH that results in deswelling and insulin transport across the membrane (reprinted from ref. 61, with permission from Elsevier Science)...

The effect of various absorption enhancers on insulin transport across the rectal membrane of albino rabbits was examined by an in vitro Us sing chamber method [18]. Insulin was unable to cross the rectal mucosa without absorption enhancers, but its transport was improved in their presence. Among these enhancers, Na glyco-cholate (NaGC) was more effective than Na taurocholate (NaTC), but less effective than Na deoxycholate (NaDC) and poly-... 

We also studied the transport of insuHn across colonic membranes in the presence of various absorption enhancers, again using the Ussing chamber method [19]. Insulin transport was enhanced by the addition of NaDC, EDTA, w-lauryl-y9-D-malto-pyranoside (LM) and Na caprate (NaCap)... 

Albin G, Horbett TA, Ratner BD. Glucose-sensitive membranes for controlled delivery of insulin Insulin transport studies. J Contr Rel 1985 2 153-164. 

Ichikawa, H., Peppas, N.A. Novel complexation hydrogels for oral peptide delivery In vitro evaluation of their cytocompatibility and insulin-transport enhancing effects using caco-2 cell monolayers. J. Biomed. Mater. Res., 67, 609, 2003. 

Factors Affecting Insulin Secretion Structure and Synthesis of Insulin Insulin Transport and Breakdown Metabolic Effects of Insulin Carbohydrate Metabolism 510 Muscle Liver... 

Fig. 6. Schematic of a chemical valve. Glucose oxidase is immobilized on a pH-responsi ve polyacrylic acid grafted onto a porous polycarbonate membrane (a) poly(acrylic acid) is in an expanded conformation that blocks insulin transport (b) the oxidation of glucose is accompanied by a decrease in pH and the transition of poly(acrylic cid) into a compact conformation that results in opening of the pores and transport of insulin. Redrawn from Ref. 82.

Figure 6.4. Schematic presentation of chem ical valve with gl ucose oxidase immobilizedon a pH-responsive polyacrylic acid grafted on a porous polycarbonate membrane A—poly(acryIic acid) is in an expanded conformation blocking insulin transport B—the oxidation of glucose is accompanied by decrease in pH and transition of poly(acrylic acid) into a compact conformation resulting in opening the pores for insulin...

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