J R Pappenheimer

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Mice, rats, or rabbits were provided with a liquid diet of 10-12% glucose (Glc), 0.5-1% creatinine, 1-2% mannitol, and mannitol labeled with 3H on a terminal carbon. Average rates of ingestion of Glc were greater than maximum rates of active, carrier-mediated Glc transport reported for the intestines of these species. The discrepancy was small in mice but(More)
T HE PENETRATION of capillary walls by water and dissolved substances appears to take place solely by processes which require no energy transformations on the part of the capillary endothelial cells. The rate of net fluid movement across the capillary wall has been shown to be simply proportional to the difference between hydrostatic and osmotic forces(More)
An hypothesis is advanced to account for the large paracellular component of absorption of nutrients by the small intestine. High concentrations of hexoses and amino acids in the immediate vicinity of transporters and cell junctions are generated by membrane-bound saccharases and peptidases. After saturation of membrane carriers, the concentrations of(More)
Fast atom bombardment-mass spectrometry (FABMS) has been used to determine the structure of the urinary sleep-promoting factor (FSu), the nature of whose components had been reported earlier. Less than 1 nmol of the underivatized substance sufficed for the FABMS experiments. The major somnogenic constituent of the purified preparation was a peptidoglycan of(More)
The structures of components of the sleep-promoting material purified from human urine were established by fast atom bombardment-mass spectrometry, as reported in the accompanying paper (Martin, S. A., Karnovsky, M. L., Krueger, J. M., Pappenheimer, J. R., and Biemann, K. (1984) J. Biol. Chem. 259, 12652-12658). We report here that two substances isolated(More)