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We and others have reported the presence of novel progastrin (PG)/gastrin receptors on normal and cancerous intestinal cells. We had earlier reported the presence of 33-36 kDa gastrin-binding proteins on cellular membranes of colon cancer cells. The goal of the current study was to identify the protein(s) in the 33-36 kDa band, and analyse its functional significance. A carbodiimide crosslinker was used for crosslinking radio-labeled gastrins to membrane proteins from gastrin/PG responsive cell lines. Native membrane proteins, crosslinked to the ligand, were solubulized and enriched by >1000-fold, and analysed by surface-enhanced laser desorption/ ionization-time of flight-mass spectrometry. The peptide masses were researched against the NCBInr database using the ProFound search engine. Annexin II (ANX II) was identified, and confirmed by matrix-assisted laser desorption/ionization-time of flight-mass spectrometry. As HCT-116 cells express autocrine PG, the in situ association of PG with ANX II was demonstrated in pulldown assays. Direct binding of PG with ANX II was confirmed in an in vitro binding assay. In order to confirm a functional importance of these observations, sense and anti-sense (AS) ANX II RNA-expressing clones of intestinal epithelial (IEC-18) and human colon cancer (HCT-116) cell lines were generated. AS clones demonstrated a significant loss in the growth response to exogenous (IEC-18) and autocrine (HCT-116) PG. We have thus discovered that membrane-associated ANX II binds PG/gastrins, and partially mediates growth factor effects of the peptides.

Design floods for major dams throughout the world are based on the probable maximum flood (PMF) which results from the probable maximum precipitation (PMP). Estimates of PMP can be made using a number of methods, the most favoured being the hydrometeorological method involving maximisation and transposition of historic storms. In this paper the in situ maximisation and storm transposition approach has been used for estimating PMP for a one‐day duration for different locations in India. Based on these PMP values a generalised map of one‐day PMP was produced. It was found that oneday PMP over the Indian region varied from 70 cm to 170 cm, with high values in the mountainous areas of the Western Ghats and in some locations in the north‐eastern parts. These results are considerably higher than those obtained using statistical analysis of daily rainfall records using Hershfield's method and they have serious implications for dam safety over much of India. Copyright © 1999 Royal Meteorological Society

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A new nonpeptide κ‐opioid compound, a cyclohexyl benzeneacetamide derivative (PD117302), has been synthesized and its affinity for the different types of opioid receptor determined. The ability of PD117302 to modify the activity of the electrically‐stimulated guinea‐pig ileum and rabbit vas deferens has also been evaluated. In binding studies using guinea‐pig brain homogenates, unlabelled PD117302 had a high affinity (Ki = 3.7 nm) at [3H]‐etorphine labelled κ sites and a low affinity at [3H]‐[d‐Ala2, MePhe4, glyol5]‐enkephalin ([3H]‐DAGOL) labelled μ sites (Ki = 408 nm) and [3H]‐SKF 10047 labelled s sites (Ki = 1.8 μm). In bioassay studies, PD117302 was a potent agonist, producing a maximum inhibition of the electrically‐evoked contractions of the guinea‐pig ileum (IC50 = 1.1 nm) and rabbit vas deferens (IC50 = 45 nm) which was naloxone‐reversible. In guinea‐pig brain, [3H]‐PD117302 bound to a high‐affinity opioid binding site with a KD of 2.7 nm and a Bmax of 3.4 pmol g−1 wet weight. The Bmax was found to be less than 50% of the Bmax values for [3H]‐etorphine and [3H]‐bremazocine suggesting that [3H]‐PD117302 may be a specific ligand for a subtype of κ receptor. [3H]‐PD117302 also bound with micromolar affinity to a non‐opioid binding site. Kinetic studies found that [3H]‐PD117302‐specific binding to the high affinity site was saturable, reaching equilibrium within 20 min at 4°C, and reversible, with a half‐life of dissociation of 3.9 min. Several unlabelled compounds with high affinities for the [3H]‐etorphine labelled κ binding site, had comparable affinities when competing for the [3H]‐PD117302‐specific high affinity binding site. In contrast, DAGOL, [d‐Ala2, d‐Leu5] enkephalin (DADLE) and [d‐Pen2, d‐Pen5] enkephalin (DPDPE) had no significant effect on [3H]‐PD117302 binding, suggesting minimal interaction with μ and δ binding sites. In autoradiography studies [3H]‐PD117302 binding sites were found throughout the brain with the greatest density in the striatum, cerebral cortex (layers V‐VI), substantia nigra, and the molecular layer of the cerebellum. Lowest levels were found in the granular layer of the cerebellum, thalamus and cerebral cortex (layers I‐IV).