This study presents experiments related to the role of solvent drag and solute drag in the transmembrane movement of nonelectrolytes in a perfused rat intestine preparation. Conditions were chosen to simulate the effects of luminal hyperosmolarity on the permeability of tracer solutes. Data are presented on net water flux, transepithelial potentials, and lumen-to-blood and blood-to-lumen tracer...

Asymmetrical (one-sided) application of penetrating water-soluble polymers, polyethylene glycols (PEGs), to a well-defined channel formed by Staphylococcus aureus alpha-toxin is shown to probe channel pore geometry in more detail than their symmetrical (two-sided) application. Polymers added to the cis side of the planar lipid membrane (the side of protein addition) affect channel conductance d...

A flow system has been used to determine the permeability of human red cell membranes to four small nonelectrolytes labeled with (14)C. The permeability coefficients, omega, in units of mol dyne(-1) sec(-1) x 10(15), are: ethylene glycol, 6; urea, 13; formamide, 22; and methanol, 131. The values for urea and formamide are in good agreement with values obtained by Sha'afi, Gary-Bobo, and Solomon...

OHNO, K., K. D. PETTIGREW, AND S. I. RAPOPORT. Louter lin2its of cercbrovasculur permeability to nonelectrolytes in the cmscir3us rc~t, Am, J, Physi& 2X3.31: H2!&N?Q7, L978 rlr Am. L Physinl.: 2kart I&c*. 2hyCL $3): H299-~3~1j 1978. Vascular permeability P in different cerebral regions of the conscious rat was determined, independently of blood flow, for “C tracers of glycerol, mannitol, sucros...

The revised general solubility equation (GSE) is used along with four different methods including Huuskonen's artificial neural network (ANN) and three multiple linear regression (MLR) methods to estimate the aqueous solubility of a test set of the 21 pharmaceutically and environmentally interesting compounds. For the selected test sets, it is clear that the GSE and ANN predictions are more acc...

The mammalian urinary bladder epithelium (urothelium) performs the important function of storing urine for extended periods, while maintaining the urine composition similar to that delivered by the kidneys. The urothelium possesses four properties to perform this function. First, it offers a minimum epithelial surface area-to-urine volume; this reduces the surface area for passive movement of s...