TITLE

SITE AND SEQUENCE OF INITIATION OF INTRACELLULAR ENZYME ACTIVATION IN EXPERIMENTAL ACUTE PANCREATITIS

AUTHOR(S)
Raraty, M.G.T.; Neoptolemos, J.P.; Petersen, O.H.; Sutton, R.
PUB. DATE
April 2003
SOURCE
Gut;Apr2003 Supplement 1, Vol. 52, pA19
SOURCE TYPE
Academic Journal
DOC. TYPE
Article
ABSTRACT
Intracellular activation of both trypsin and cathepsin B is known to occur early in the course of acute pancreatitis. This study aimed to determine the time course and subcellular location of: such activation and its relationship to abnormal Ca[sup 2+] signalling. Isolated mouse pancreatic acinar cells were loaded with 10 µM IPR-CMAC (a fluorescent substrate specific for trypsin) and/or (FR)2-R110 (specific for cathepsin B), together with fura-2 for measurement of cytosolic Ca[sup 2+] ([Ca[sup 2+]],) and were then perifused with stimuli. Enzyme activation was visualised by confocal microscopy, and changes in cellular morphology by electron microscopy. Cells exposed to 10nM CCK or 2 pM thapsigargin showed a rapid rise in [Ca[sup 2+]], followed by a modest sustained elevation. Within 300 seconds of application of: the stimulus, fluorescence appeared within multiple discrete rounded compartments approximately 1 pm in diameter within the granular pole of the cell. These gradually enlarged with continued stimulation and became less distinct. By 60 min, typical vacuoles were apparent on electron microscopy. The fluorescence from both enzyme substrates developed within spatially indistinguishable compartments at the apical pole of the cell but trypsinogen activation preceded cathepsin B activation by a mean of 85 ± 34s. Trypsinogen activation occurred more rapidly and reached a plateau 200 seconds earlier than that from cathepsin B. Attenuation of the abnormal [Ca[sup 2+]][sub i] signals with the Ca[sup 2+] chelating agent BAPTA prevented both trypsinogen activation and vacuolisation. These findings build on our previous findings (PNAS 2000;97:13126-31) and confirm the crucial role of abnormal cytosolic Ca[sup 2+] signals in the initiation of intracellular enzyme activation. Trypsinogen activation occurs within zymogen granules, which then become vacuoles. These results are consistent with the central role trypsinogen activation is thought to play in...
ACCESSION #
9747383

 

Related Articles

  • Clinical value of serum immunoreactive trypsin concentration. Ruddell, W.S.J.; Mitchell, C.J.; Hamilton, I.; Leek, J.P.; Kelleher, J. // British Medical Journal (Clinical Research Edition);11/28/1981, Vol. 283 Issue 6304, p1429 

    Examines the serum immunoreactive trypsin concentration on patients with chronic pancreatic disease. Comparison of patients differential diagnosis; Difference on the concentration of immunoreactive trypsin; Effectivity of the immunoreactive trypsin to patients with pancreatitis.

  • Serum complex of trypsin 2 and alpha1 antitrypsin as diagnostic and prognostic marker of acute... Hedstrom, Johan; Sainio, Vesa // BMJ: British Medical Journal (International Edition);8/10/96, Vol. 313 Issue 7053, p333 

    Estimates the usefulness of serum concentrations of the complex of trypsin 2 and alpha 1 antitrypsin in diagnosing and assessing the severity of acute pancreatitis. Clinical features of acute pancreatitis; Differentiating acute pancreatitis from extrapancreatic disease; Accurate markers of...

  • Mutational analysis of the pancreatic secretory trypsin inhibitor gene in familial and juvenile pancreatitis in Japan. Kuwata, Kinuko; Hirota, Masahiko; Nishimori, Isao; Otsuki, Makoto; Ogawa, Michio // Journal of Gastroenterology;2003, Vol. 38 Issue 4, p365 

    Background. Mutations in the pancreatic secretory trypsin inhibitor (PSTI) gene have been reported in patients suffering from chronic pancreatitis. The aim of the present study was to investigate whether similar gene mutations are present in familial and juvenile pancreatitis patients in Japan....

  • The role of trypsin, trypsin inhibitor, and trypsin receptor in the onset and aggravation of pancreatitis. Hirota, Masahiko; Ohmuraya, Masaki; Baba, Hideo // Journal of Gastroenterology;Sep2006, Vol. 41 Issue 9, p832 

    Trypsin activity is properly suppressed in the pancreatic acinar cells under normal conditions. A small amount of trypsinogen is converted to active trypsin and inactivated by pancreatic secretory trypsin inhibitor (PSTI), thereby preventing damage to pancreatic acinar cells as a first line of...

  • Do point mutations in the PSTI (SPINK1) gene truly contribute to the pathogenesis of chronic pancreatitis? Shimosegawa, Tooru // Journal of Gastroenterology;2001, Vol. 36 Issue 9, p645 

    Editorial. Examines the role of point mutations in the pancreatic secretory trypsin inhibitor (PSTI) gene in the pathogenesis of chronic pancreatitis. Characterization of chronic pancreatitis; Information on PSTI; Incidence of gene mutations in unrelated patients with idiopathic chronic...

  • Functional analysis of recombinant pancreatic secretory trypsin inhibitor protein with amino-acid substitution. Kuwata, Kinuko; Hirota, Masahiko; Shimizu, Hiroyuki; Nakae, Masanori; Nishihara, Shoji; Takimoto, Akio; Mitsushima, Kenji; Kikuchi, Norihisa; Endo, Kazuaki; Inoue, Masayasu; Ogawa, Michio // Journal of Gastroenterology;2002, Vol. 37 Issue 11, p928 

    Background. We hypothesized that mutation of the pancreatic secretory trypsin inhibitor (PSTI) gene may promote a predisposition to pancreatitis, possibly by reducing the inhibition of trypsin activity. Based on this hypothesis, we performed a biochemical analysis of recombinant PSTI protein....

  • Serum Immunoreactive Trypsin Response to Secretin Injection in Patients with Chronic Pancreatitis. Vezzadini, P.; Gullo, L.; Sternini, C.; Bonora, G.; Priori, P.; Labò, G. // American Journal of Gastroenterology;Mar1984, Vol. 79 Issue 3, p213 

    Serum immunoreactive trypsin response to secretin injection (75 clinical units iv over a 2-min period) was studied in patients with chronic pancreatitis and in control subjects. Secretin stimulation caused a slight but significant increase of basal serum immunoreactive trypsin concentration in...

  • Comparison of Elastase-1 with Amylase, Lipase, and Tryspin-Like Immunoreactivity in the Diagnosis of Acute Pancreatitis. Flamion, B.; Delhaye, M.; Horanyi, Z.; Delange, A.; Demanet, H.; Quenon, M.; Van Melsen, A.; Cremer, M.; Delcourt, A. // American Journal of Gastroenterology;Jun1987, Vol. 82 Issue 6, p532 

    Serum elastase-1, amylase, lipase, and trypsin-like immunoreactivity were measured in a group of 17 consecutive patients with acute pancreatitis. When assayed within 24 h of the onset of symptoms, all enzymes were found to be elevated, thus showing similar sensitivity. Elastase-1 did not improve...

  • Spotting acute pancreatitis. Schlapman, Nancy; Boyd, Leslie // RN;Nov2001, Vol. 64 Issue 11, p54 

    Focuses on the diagnosis of acute pancreatitis. Estimated number of people in the United States who develop acute pancreatitis; Details on the enzymatic activity of the pancreas; Influence of trypsin in the onset of acute pancreatitis.

Share

Read the Article

Courtesy of VIRGINIA BEACH PUBLIC LIBRARY AND SYSTEM

Sign out of this library

Other Topics