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In order to identify proguanylin-secreting cells, we have raised an antiserum against the synthetic fragment of human proguanylin (1–15) and have examined the proguanylin-positive cells in the human and rat gastrointestinal tract by immunohistochemical methods. Numerous proguanylin (1–15)-immunoreactive cells were found in the gastrointestinal tract. They were either pyramidal or spindle shaped in the stomach. Spindle-shaped cells, frequently possessing long slender processes, were located at the base of the pyloric epithelium and did not extend to the lumen. In the duodenum and jejunum, these cells were mostly pyramidal in shape and often had a slender process towards the lumen. The immunostaining was completely blocked by the human proguanylin (1–15) fragment. Paneth and goblet cells were negative against this antiserum. The number of serotonin-positive cells was much larger than that of proguanylin-positive cells in all the segments tested. The number of proguanylin-positive cells decreased from the jejunum to the ileum and very few cells were observed in the colon. In contrast to serotonin-positive cells, most somatostatin-positive cells were also positive for proguanylin. Thus, proguanylin (1–15) or its related protein appears to coexist with somatostatin in intestinal endocrine D cells which may be a source of circulating proguanylin. Proguanylin, like somatostatin, may also regulate intestinal function as a local regulator. [ABSTRACT FROM AUTHOR]

Background: Excessive consumption of alcohol is involved in the onset of pancreatitis. However, most of heavy drinkers do not always develop chronic pancreatitis. Various genetic factors appear to be involved in these individual differences in onset of chronic alcoholic pancreatitis. Here we investigated a possible association of alcoholic pancreatitis with polymorphisms of the various genes belong to the phase II detoxification enzymes responsible for metabolism of the oxidative compounds, and the several genes that have relevance to inherited pancreatitis. Methods: The subjects consisted of 53 patients with chronic alcoholic pancreatitis, 54 alcoholic patients without pancreatic dysfunction, and 42 healthy individuals. DNA was extracted from the peripheral nucleated blood cells of all subjects and genetic mutations and subtypes were analyzed by the PCR and RFLP methods. We examined the correlation between chronic alcoholic pancreatitis and variants of the phase II detoxification enzymes such as Glutathione S-transferase M1 (GSTM1), glutathione S-transferase theta 1 (GSTT1), NADPH-quinone oxidoreductase 1 (NQO1), and N-acetyl transferase (NAT2). In addition, genes of lipoprotein lipase (LPL), cationic trypsinogen (PRSS1), pancreatic secretory trypsin inhibitor (PSTI), and cystic fibrosis transmembrane conductance regulator (CFTR) were also analyzed. Results: Frequencies of the gene deletion of GSTM1 and GSTT1 in addition to the C-allele frequency of NQO1 tended to be higher in the alcoholic patients with (AlCP) or without pancreatic dysfunction (Alc) than in the healthy controls although the difference was not significant. The NAT2 gene showed no relation with Alc and AlCP patients. PSTI, LPL, PRSS1, and CFTR genes presented no association with chronic alcoholic pancreatitis. Conclusions: All genes analyzed in the present study lacked association with chronic alcoholic pancreatitis. However, the gene deletion of GSTM1 and GSTT1, and the C-allele of NQO1 cannot be ruled out for association with alcoholism. [ABSTRACT FROM AUTHOR]

Chronic and excessive consumption of alcohol is an important factor responsible for the onset of pancreatitis. However, the incidence of chronic pancreatitis in heavy drinkers differs in individuals, suggesting that these individual differences may involve various genetic and environmental factors. In the present study, we investigated an association of alcoholic pancreatitis with polymorphisms of the various genes related to metabolism of the oxidative compounds. We analyzed polymorphisms of NADPH-quinone oxidoreductase 2 (NQO2), multidrug resistance 1 (MDR1), alcohol dehydrogenase 1B (ADH1B) and lipoprotein lipase (LPL). The subjects consisted of 53 patients with chronic alcoholic pancreatitis (AlCP), 54 alcoholic patients without pancreatic dysfunction (Alc), and 42 healthy individuals. DNA samples were prepared from the peripheral blood of all subjects, and the genetic mutations were analyzed by polymerase chain reaction and restriction fragment length polymorphism methods. The ADH1B gene frequencies were significantly different between healthy controls and Alc patients ( P < 0.001), and also between AlCP and Alc patients ( P < 0.05). However, no significant difference was found between healthy controls and AlCP patients. The gene frequencies of MDR1 (3435C > T) and MDR1 (2677G > A/T) of patients with AlCP or Alc were different when compared with healthy controls, although the difference was not significant. The NQO2 and LPL genes showed no relation with Alc and AlCP patients. The ADH1B* 1 gene frequency in AlCP was significantly lower compared with Alc. We speculate that the ADH1B* 1 gene may function by reducing vulnerability to the onset of alcoholic pancreatitis. Other genes analyzed in the present study lacked association with AlCP. [ABSTRACT FROM AUTHOR]

Aberrant HCO3- transport is a hallmark of cystic fibrosis (CE) and is associated with aberrant Cl-dependent HCO3- transport by the cystic fibrosis transmembrane conductance regulator (CFTR). We show here that HCO3- current by CFTR cannot account for CFTR-activated HCO3- transport and that CFTR does not activate AE1-AE4. In contrast, CFTR markedly activates Cl- and OH-/HCO3- transport by members of the SLC26 family DRA, SLC26A6 and pendrin. Most notably, the SLC26s are electrogenic transporters with isoform-specific stoichiometries. DRA activity occurred at a Cl-/HCO3- ratio &ges;2. SLC26A6 activity is voltage regulated and occurred at HCO3-/Cl- &ges;2. The physiological significance of these findings is demonstrated by interaction of CFTR and DRA in the mouse pancreas and an altered activation of DRA by the R117H and GS51D mutants of CFTR. These findings provide a molecular mechanism for epithelial HCO3- transport (one SLC26 transporter-electrogenic transport; two SLC26 transporters with opposite stoichiometry in the same membrane domain-electroneutral transport), the CE-associated aberrant HCO3- transport, and reveal a new function of CFTR with clinical implications for CE and congenital chloride diarrhea. [ABSTRACT FROM AUTHOR]