Effect of pancreatic duct ligation on exocrine pancreatic function and structure in the rabbit

Summary 4 weeks after pancreatic duct ligation in the rabbit, fecal and luminal chymotrypsin were detected in concentrations similar to the control group. Pancreatic changes in the ligated group were marked dilatation of the main pancreatic duct, proliferation and distention of ductules and fibrosis. Despite pancreatic duct ligation and fibrosis, proteolytic enzymes continued to secrete into the duodenal lumen. These results suggest that pancreatic duct ligation in the rabbit is not associated with total pancreatic insufficiency.This study was supported by the Kansas University Endowment Association (Grant No. 73-2550), General Research Support (Grant No. 2553 and 1522-14) and a grant from Kaw Valley Heart Association.     

Effect of suppression of endocrine or exocrine pancreatic function in hemorrhagic shock

Summary Somatostatin did not influence the pathologic consequences of hemorrhagic shock, but pancreatic duct ligation prevented the post-oligemic decline of arterial pressure and formation of toxic factors. These results indicate that pancreatic acinar cells release myocardial depressant factor and are important in the pathophysiology of shock.Supported in part by research grant No. HL-17745 from the National Heart, Lung and Blood Institute of the NIH.Acknowledgments. We gratefully acknowledge the expert technical assistance of Mary Ann Gaffney, Richard Levin and Kathleen Shupe during the course of these investigations. We also thank Dr William D. Cash of Ciba-Geigy Co., Ardsley, New York, for the supply of somatostatin.     

Effect of suppression of endocrine or exocrine pancreatic function in hemorrhagic shock.

Somatostatin did not influence the pathologic consequences of hemorrhagic shock, but pancreatic duct ligation prevented the post-oligemic decline of arterial pressure and formation of toxic factors. These results indicate that pancreatic acinar cells release myocardial depressant factor and are important in the pathophysiology of shock.     

Endocrine and exocrine pancreatic function after camostate-induced growth of the organ

It is well known that oral administration of camostate induces hyperplasia and hypertrophy of the rat pancreas. It is not clear, however, whether pancreatic hormone and enzyme secretion are affected by camostate treatment.In rats, daily administration of 200 mg camostate/kg b. wt for 14 days significantly increased pancreatic weight and pancreatic content of DNA, protein, amylase, lipase, trypsin and chymotrypsin, as well as the amount of insulin, glucagon and somatostatin. In the intact animal, blood glucose levels and serum concentrations of insulin and glucagon in response to an oral glucose load were not impaired after camostate treatment. In the isolated perfused pancreas, however, insulin and glucagon secretions were reduced, whereas somatostatin release was not affected. The volume of pancreatic juice produced by the unstimulated isolated perfused organ, as well as protein and enzyme secretion, were increased after camostate treatment. Likewise, the isolated perfused pancreas from camostate-treated rats secreted a larger volume of pancreatic juice and more protein in response to cholecystokinin (CCK), while enzyme secretion was affected in a non-parallel manner: amylase release was markedly reduced, lipase release was unchanged, and release of trypsin and chymotrypsin was increased.     

Effect of ligating the pancreatic duct on the intestinal pH in rabbits]

In rabbits whose pancreatic ducts were ligatured, significant pH changes were observed in the anterior parts of the digestive tract (antrum and duodenum) but not in the posterior parts (jejunum and ileum) as could have been expected. These changes do not seem to be directly related to the lack of pancreatic juice, which leads one to think that, in the rabbit this secretion only plays a very limited role in the neutralisation processes.     

Xenopsin stimulates exocrine pancreatic secretion in the dog

Summary The octapeptide xenopsin, previously isolated from amphibian skin, stimulates exocrine pancreatic secretion of bicarbonate and protein in conscious dogs and increases the volume of secretion. This effect is shown in the dose range of 1.25 up to 160 pmoles kg^–1min^–1 The high potency of this peptide is suggestive of a possible physiological role of xenopsin in mammals.This work was supported by the Deutsche Forschungsgemeinschaft Fe 127/4.     

Effect of nerve stimulation,denervation, and duct ligation,on kallikrein content and duct cell granules of the cat's submandibular gland

Summary Various procedures which reduce or deplete the kallikrein content of the cat's submandibular gland correspondingly reduce the number of apical granules in the striated duct cells. The kallikrein content is greatly reduced after chronic parasympathetic but not after sympathetic nerve section which suggests that the parasympathetic innervation is required for synthesis or storage of this enzyme.We wish to acknowledge the valuable assistance of Dr T. Nihei and Mr. J. Wimal in some of the enzyme measurements.This work was supported by grants from the Medical Research Council of Canada and the Alberta Heart Foundation.     

Hepatic proline after bile duct ligation in rats

Since biliary hyperplasia of fascioliasis correlated with hepatic proline level, we examined the occurrence of a similar chemical stimulus during bile obstruction. Uptake of tritiated proline and glycine rose in both hepatocytes and a bile duct enriched cell fraction, following duct ligation in rats. The increased hepatic content of proline but not glycine suggests that proline has a role in post-obstructive biliary proliferation.     

Factors influencing the intestinal phase of pancreatic exocrine secretion in the turkey

The present study was done to investigate the factors regulating the intestinal phase of exocrine pancreatic secretion in the turkey. The intestine of turkeys equipped with pancreatic fistulas was perfused with peptone solution, fat emulsion and hydrochloric acid (HCl), and pancreatic flow and protein output were measured. Neither peptone solution nor fat emulsion had any effects on pancreatic secretion. HCl enhanced the flow rate of pancreatic juice but not protein output. To clarify the neural mechanism of this phenomenon, the vagal postganglionic blocker atropine was continuously infused and pancreatic secretion in response to intestinal HCl was measured. Atropine completely suppressed both pancreatic flow and protein output. It is suggested that the avian intestinal phase of pancreatic secretion is mainly controlled by cholinergic action though HCl stimulation.     

Expressed protein ligation: a resourceful tool to study protein structure and function

This review outlines the use of expressed protein ligation (EPL) to study protein structure, function and stability. EPL is a chemoselective ligation method that allows the selective ligation of unprotected polypeptides from synthetic and recombinant origin for the production of semi-synthetic protein samples of well-defined and homogeneous chemical composition. This method has been extensively used for the site-specific introduction of biophysical probes, unnatural amino acids, and increasingly complex post-translational modifications. Since it was introduced 10 years ago, EPL applications have grown increasingly more sophisticated in order to address even more complex biological questions. In this review, we highlight how this powerful technology combined with standard biochemical analysis techniques has been used to improve our ability to understand protein structure and function.     

Effect of cadmium on polyribosome structure and function in mouse liver

Summary Cadmium chloride injected to mice (20 moles/kg) provokes in the livers a degradation of polyribosomes and diminishes their protein synthetic ability measured in vitro. CdCl₂ added in a final concentrations between 30 and 100 M to the protein synthetic cell-free system derived from livers of control mice inhibits its activity.Acknowledgments. We are grateful to Prof. P. Sokoli for helpful discussion. The work was supported by Wellcome Trust grant and by a gift of chemicals from Kemika, Zagreb. We are grateful to both these organizations.     

Secretory responses and choline acetylase of the rat's submaxillary gland after duct ligation

Zusammenfassung Abbinden des Ausführungsganges der Submaxillarisdrüse der Ratte führt zu ihrer Gewichtsabnahme. Nach i.v. Gaben von Methacholin und Adrenalin verschwindet die Sekretion innerhalb von 4–6 Tagen nach der Operation, während bei Pilokarpin noch eine sehr verminderte Speichelsekretion persistiert. Die spezifische Fähigkeit der sekretorischen Zellen war zusehends verringert. Die Gesamtaktivität der Cholin-Acetylase blieb ähnlich derjenigen der Kontrolldrüsen, was für eine unveränderte Funktion des Parasympathikus spricht.     

Smooth muscle of the pancreatic duct of the cat and its innervation

Zusammenfassung In der Wandung desDuctus pancreaticus major der Katze wird eine dünne Schicht von Muskelfaserzügen beschrieben. Histochemisch wird festgestellt, dass es sich bei fehlender adrenergischer um cholinerge Innervation dieser Muskelzellen handelt.

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J. R. Garrett, wishes to express his gratitude to the Royal Society for travel grants that made this work possible.     

Renal function following complete ligation of the renal artery

Zusammenfassung Totale Unterbindung der Nieren arterie führt zu fast vollständigem Erlöschen der Funktion der betreffenden Niere. Wird etwa 81 bis 110 Tagnach der Unterbindung die andere Niere entfernt, se können Hunde ohne Symptome von Niereninsuffizieno überleben: die Entwicklung eines Kollateralkreislaufez stellt die Funktion der ischämisierten Niere wieder her. s