Glucocorticoid receptor concentration modulates glucocorticoid regulated gene expression in rat pancreatic AR42J cells

Glucocorticoid receptor concentration modulates glucocorticoid regulated gene expression in rat pancreatic AR42J cells

April 1995 • L A C K S O F T R O P H I C EFFECT BY ORAL A D M I N I S T R A T I O N OF CAMOSTATE AND OF CERULEIN INDUCED ACUTE P A N C R E A T I T I ...

176KB Sizes 0 Downloads 81 Views

April 1995

• L A C K S O F T R O P H I C EFFECT BY ORAL A D M I N I S T R A T I O N OF CAMOSTATE AND OF CERULEIN INDUCED ACUTE P A N C R E A T I T I S IN A N E W RAT M O D E L N O T E X P R E S S I N G C C K - A - R E C E P T O R GENE. A. Jimi, K. Miyasaka, S. Kanai, M. Ohta, A. Funakoshi. 1st. Dept. Pathol. Kurume Univ. Fukuoka830, Dept oI IZlin. Physiol. T o k y o Metropolitan Inst. Gerontol., Tokyo-173, National K y u s h u Cancer Center, Fukuoka-815 W e h a v e r e p o r t e d that O t s u k a L o n g - E v a n s T o k u s h i m a Fatty (OLETF) rats revealed none or less expression of CCK-Areceptor gene in the pancreas (BBRC, 1994), although CCKB - r e c e p t o r gene was expressed in the brain (Neurosci. LetL 1994). To c o n f i r m the c o n t r i b u t i o n of C C K - A - r e c e p t o r functions, we e x a m i n e d the effect of oral administration of c a m o s t a t e (protease inhibitor) on the pancreas and w h e t h e r an e x c e s s d o s e of c e r u l e i n i n j e c t i o n p r o d u c e d a c u t e pancreatitis in O L E T F rats. These were compared with the control ( L E T O ) rats. Methods: The rats ( 5 - w e e k s old) w e r e divided into two groups, given standard diet and diet containing 0.1% camostate for 7 days. The protein, D N A , c h y m o t r y p s i n , a m y l a s e and insulin contents in the pancreas w e r e m e a s u r e d , and the h i s t o l o g i c a l e x a m i n a t i o n w a s conducted. For the acute experimental pancreatitis, cerulein (40 ~tg/kg) w a s injected i n t r a p e r i t o n e a l l y twice at 1-h interval and the rats w e r e sacrificed 7-h after the first injection. The p l a s m a a m y l a s e level and the histological chan~.e w e r e e x a m i n e d . R e s u l t s : Camostate treatment significantly increased the pancreatic wet weight and protein content, and altered the e n z y m e c o m p o s i t i o n s (an increase m c h y m o t r y p s i n and a decrease m amylase) in L E T O rats, but not in O L E T F rats. The insulin and D N A concentrations in L E T O rats rather decreased but their total contents w e r e c o n s t a n t o r increased, respectively, because of increase in pancreatic wet weight. Histologically, pancreatic acinar cells of L E T O rats b e c a m e hypertrophic, whereas no c h a n g e in islets. H o w e v e r , all parameters did not change or tended to decrease in O L E T F rats. An excess dose of cerulein produced acute e d e m a t o u s p a n c r e a t i t i s associated with the increase in p l a s m a amylase level in L E T O rats, however, no change in O L E T F rats. C o n c l u s i o n s : These findings indicate that trophic effect on exocrine gland and cerulein induced acute pancreatitis are mediated specifically by C C K - A - r e c e p t o r s .

• EARLY PREDICTORS OF POST-THERAPEUTIC ERCP PANCREATITIS: COMPARISON OF CLINICAL EVALUATION AND SERUM AMYLASE. R.M. Kaikaus, G.K. Johnson, J.E. Geenen, M.J. Schmalz, D.J. Geenen, A.B. Ross, M. F. Catalano, and the Midwest Pancreatic Group. St. Luke's Hospital, Racine, WI, and St. Luke's Medical Center, Milwaukee, WI. Pancreatitis occurs in 5-13% of patients undergoing ERCP, and occurs more frequently, and with greater severity, in those undergoing therapeutic interventions. Early predictors of pancreatitis would be important in the management of these patients. As part of a multicenter study assessing the usefulness of a non-ionic contrast agent, we have evaluated the utility of clinical assessment, as well as that of serum amylase level obtained at 2-4 hours, in identifying those patients who are likely to develop post-therapeutic ERCP pancreatitis. METHODS: A total of 828 consecutive patients undergoing therapeutic ERCP (both pancreatic and biliary interventions) were evaluated clinically both before and at 2-4 hours after the procedure. On the basis of symptoms (nausea, emesis, pain) and physical examination, a judgment was made whether or not these patients had developed pancreatitis. Serum amylase levels were drawn 1-4 days prior to the procedure and again at 2-4 hrs after the procedure. Patients with suspected pancreatitis were hospitalized. Definitive diagnosis of pancreatitis was made on the basis of clinical, laboratory, and radiological data. RESULTS: Of the 828 patients, 102 (12.3 %) developed pancreatitis. Clinical evaluation correctly predicted pancreatitis in 72 (70.6 %) patients, while serum amylase was >2x normal (>250 u/I) in 81 (79 %) patients. In 55 (54 %) patients both clinical evaluation and amylase elevation suggeswcd pancreatitis, while in 90 (88 %) patients either one or both of these two indicators of pancreatitis was present. In 12 (11.7%) patients, both indicators were absent. Of the 726 patients without pancreatitis, only 8 were suspected clinically of having developed pancreatitis, while 116 had amylase >250 u/1 at 2-4 hrs. Only in 5 patients without pancreatitis did both the 2-4 hour clinical evaluation and elevated amylase levels incorrectly suggest pancreatitis. EVALUATION AT 2-4, HRS Clinical Dx(+) 70 99 90 96 Amylase $ 79 84 41 97 Clinical Dx(+) & Amylase $ 54 99 92 94 KEY: PPV: Positive predictive value; NPV: Ne~alive predictive value. CONCLUSIONS: Both 2-4 hour clinical evaluation and serum amylase miss a significant number of patients who have developed post-therapeutic ERCP pancreatitis. On the other hand, a negative clinical evaluation predicts a very low likelihood of developing pancreatitis, while the serum amylase level does not contribute any additional useful information.

Pancreatic Disorders

A363

MUCINOUS CYSTADENOMAS OF THE PANCREAS ARE BEST DIAGNOSED BY PANCREATOSCOPY M. Jung, A. Zipf, D. Schoonbroodt, G. Herrmann*, H. Wenisch**, W.F. Caspary, Med. Clinic II, Inst. of Pathology* and Dept. of Surgery**, J.W. Goethe-University Frankfurt/M., Germany Introduction: Mucinous Cystadenomas of the pancreas are rare premalignent tumors that tend to develop into invasive cystadenocarcinomas. Mucinous Cystadenomas are classified as Ductectatic Mucinous Cystadenomas (DMC) and as Intraductal Papillary Neoplasms (IPN). Hereby we report the diagnosis of 5 Cystadenomas by pancreatoscopy. Methods: From 1'93 to 12'94 20 pancreatoscopies were performed for unclear intralurninal formations or stenoses of the main pancreatic duct. Pancreastoscopy was done in mother-baby-technique by two experienced endoseopists, using the 3,2 mm Olympus prototype. In 5 cases (3 m, 2t~ 52-80 ys; r: 65,4 ys) a cystadanoma of the main pancreatic duct with dissiminated tumor growth was diagnosed both macroscopically and histologically. There were 4 duct-ectated types and one 3 mm small intraductal papillary neoplasm without visible mucus hypersecretion. In all cases a slightly (lx) or a more than 7 mm dilated (4x) pancreatic duct with intraluminal formations (ERCP) were the indications for pancreatoscopy. The endoscopic procedure included sphincterotomy of the pancreatic papilla and final drainage by a nasopancreatic tube (24 tl). No complications due to endoscopy were observed. As a consequence of panereatoscopy 3 patients underwent Whipple's operation. No cystadenocarcinomas were found in the resected specimen. The further clinical course was uneventful. Because of age and concomitant diseases the other two patients were treated conservatively. Conclusions: Pancreatoscopy, a new method for direct intraductal visualisation established the correct diagnosis of unclear formations of Wirsung's duct. In all 5 cases previous examinations (abdominal ultrasound, CT-scan, ERCP) failed to give a correct diagnosis. Pancreatoscopy, using the 3,2 mm scope becomes the method of choice in unclear intraluminal masses of the pancreas. This new procedure seems to be essential to diagnose mucinous cystadenomas, resulting in a early resection and in a better prognosis.

Glucocorticoid receptor concentration modulates glucocorticoid regulated gene expression in rat pancreatic AR42J cells. Astrid Kaiser, Emst-Otto Riecken and Stefan Rosewicz Dept. of Gastroenterology, Klinikum Benjamin Franklin, FU Berlin, FRG Glucocorticoids are important regulators of growth, differenUatian and digestive ermymes in the rat exocrme pancreas. These pleiotropic effects are mediated by the cytoplasmatic glucocorticeid receptor (GR). Little is currently known about the modulatory role for GR in the exocrine pancreas. Therefore the current study was designed to determine the role of altered intracellular GR concentrations in respect to the sensitivity of positively as well as negatively glucocurticoid regulated exocrine pancreatic genes. As a model system for the rat exocrine pancreas the rat pancreatic acinar coil line AR42J was chosen. Treatment of AR42J cells with the antiprogestm RU 38 486 resulted in a time- and dose-dependent decrease of GR protein concentration to 50 % of control cells. A selective increase of intracoUular GR protein concentration to 190 % of control cells was obtained by incubation of AR42J cells with the phosphodiesterase inhibitor IBMX. This effect was exactly reproducible by incubating AR42J cells with the physiological pancreatic acinar cell ligand vasoaotive intestinal peptide (VIP). VIP activates the adenylatcyclase complex, indicating that increased GR concentrations are due to an increase in intracollular cAMP concentrations. Using nuclear run on analysis we demonstrated that incubation of AR42J ceils with dexamethasone resulted in a time-dependent transcriptional stimulation of amylase gene expression (appr. 5-fold) and a transcriptional inhibition of bombesin receptor (BR) gene expression. We next investigated the effects of decreased and elevated intracellular GR concentrations on glucocotticoid stimulated amylase and glucocorticoid inhibited bombesin receptor geoe expression. Decreasing intracellular GR concentration to 50 % by preincubation with RU 38486 resulted in a significant attenuation of dexamethasone regulated amylase and BR gene expression. In contrast, increasing intracellular GR concentration 2-fold by preineubation with IBMX si~uficantly e~daanced the glucocorticoid inhibition of BR gene expression whereas dexam~hasone stimulated amylase gene expression remained unaltered. Moreover, the effects of elevated GR concentrations caused by IBMX on dexamethasone mediated bombesin receptor gene regulation could be exactly reproduced by preincubating AK42J cells with VIP. These data demonstrate that a rather tight control of intracollular GR concentrations modulate positively as well as negatively glucocorticoid regulated genes in the rat pancreatic acinar cell line AR42J. Modulation of intmcoUular GR concentration by the physiological pancreatic acinar cell lignnd VIP suggests that a complex interaction between peptide and steroid hormones regulates glucecorticoid sensitivity of the pancreatic acinar coll.