Yoshihiko Hirotani

Distinctive Effects of Glicentin, GLP-1 and GLP-2 on Adaptive Response to Massive Distal Small Intestine Resection in Rats

We previously reported the enhancing effect of methionyl-rat glicentin on the intestinal adaptive response to 70 % resection of small intestine in rats. 1 Another intestinal proglucagon derived peptide (PDGP) GLP-2 is now attracting attention as a novel potent growth promoting factor in the intestine. 2 The study reported here aimed at using synthetic peptides to determine the specific features of glicentin, GLP-1, and GLP-2 in terms of their effect on adaptive response to distal small intestinal resection in rats.

Preliminary study on sustained-release particles prepared with hydrogenated soya phospholipid and cholesterol

Abstract Granules prepared with hydrogenated soya phospholipid and cholesterol caused the sustained release of indomethacin in a medium of pH 6.8, and a release of apparent zero-order kinetics was observed. However, the release of indomethacin seemed to occur by the leaching mechanism, proposed by Higuchi (1963). In the scanning electron micrographs, holes on the granule surface were observed, and the numbers and size of these holes increased with immersion time. Thus, the increase of the volume of the infiltrated solvent into the matrix along with the immersion time may result in the release of indomethacin from the granules in zero-order kinetics.

Immunochemical characterization and measurement of neuronal type nitric oxide synthase in human neuroblastoma NB-OK-1 cell using novel anti-synthetic peptide antibody and specific immunoassay system.

We developed a sensitive and specific immunoassay system for human neuronal nitric oxide synthase (hnNOS) using synthetic hnNOS(998-1024) peptide and anti-hnNOS(998-1024) antibody. The novel antibody and radioimmunoassay system revealed a typical nNOS protein in human neuroblastoma NB-OK-1 cell (160 kDa, 180 fmol/10(6) cells). The kinetic parameters of the enzyme were K(m)=4.88 microM and V(max)=4.34 pmol/min/mg protein for L-arginine. On incubation of NB-OK-1 cell for 24 h, betamethasone phosphate decreased both nNOS-immunoreactivity (nNOS-IR) and enzymatic activity in the cell dose-dependently. On the other hand, pituitary adenylate cyclase activating polypeptide(1-38) (PACAP38) increased both nNOS-IR and enzymatic activity at concentrations of 10(-10) and 10(-9) M, but inversely decreased both at 10(-7) M. These suggest the positive and negative implications of endogenous NO in proliferation and differentiation of the cell, which support mitogenic activity of NO generated by nNOS in the cell. The present findings also provided evidence that the quantitative change of nNOS protein controls the integrated activity of the enzyme in the cell and, in turn, substantiate the validity and reliability of the present immunoassay system for hnNOS and its practical usefulness.