Osmotic stimulation of pepsin secretion in the rat

  • Juhani Puurunen
  • Erik Westermann


The effect of the osmolarity of intragastric instillates on pepsin secretion was studied in rats anaesthetised with urethane. Irrigation of the stomach with solutions of sucrose and NaCl, resp. caused a concentration-dependent increase in pepsin output. A stimulation was observed already by hypotonic solutions and the maximal effect was obtained by 300 m-osmole/l of sucrose and by 600 m-osmole/l of NaCl (13-and 10-fold stimulation resp.). A similar time course in the increase of pepsin output was produced by hyperosmotic solutions (600 m-osmole/l) of sucrose, urea, NaCl and choline chloride. Pepsin output was stimulated maximally within 30 min and decreased thereafter, but remained at about 4–6-fold higher levels than during the previous irrigation with distilled water. Replacement of hyperosmotic instillates by distilled water reduced pepsin secretion to the inital level. Hypertonic ethanol (600 m-osmole/l) increased pepsin output only slightly. Vagotomy, pretreatment with atropine (1 mg/kg i.v.) or cimetidine (5 mg/kg i.v.), local anaesthesia of the gastric mucosa with 4% lidocaine or intravenous infusion of PGE2 (2 μg/kg x min) did not antagonise the stimulation of pepsin output induced by hyperosmotic NaCl (600 m-osmole/l). The results indicate that the increase of the osmolarity of intragastric instillates stimulates pepsin secretion in the rat without involvement of neural (vagal or local cholinergic reflexes) or hormonal mechanisms (release of gastrin) which are known to stimulate gastric secretion in the gastric phase.

Key words

Pepsin secretion Osmolarity Intragastric instillation 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Altamirano, M.: Action of solutions of reduced somotic concentration on the dog gastric mucosa. Am. J. Physiol. 216, 25–32 (1969a)Google Scholar
  2. Altamirano, M.: Action of concentrated solutions of non-electrolytes on the dog gastric mucosa. Am. J. Physiol. 216, 33–40 (1969b)Google Scholar
  3. Anson, M. L., Mirsky, A. E.: The estimation of pepsin with haemoglobin. J. Gen. Physiol. 16, 59–63 (1932)Google Scholar
  4. Assouline, G., Leibson, V., Danon, A.: Stimulation of prostaglandin output from rat stomach by hypertonic solutions. Eur. J. Pharmacol. 44, 271–273 (1977)Google Scholar
  5. Bergegardh, S., Olbe, L.: Gastric acid response to antrum distention in man. Scand. J. Gastroenterol. 10, 171–176 (1975)Google Scholar
  6. Bynum, T. E., Johnson, L. R.: Stimulation of human pepsin output by topical hydrochloric acid. Am. J. Dig. Dis. 20, 607–612 (1975)Google Scholar
  7. Cieszkowski, M., Konturek, S. J., Obtulowicz, W., Tasler, J.: Chemical stimulatory mechanism in gastric secretion. J. Physiol. (Lond.) 246, 143–157 (1975)Google Scholar
  8. Davenport, H. W.: Physiology of the digestive tract, pp. 112–113. Chicago: Year Book Medical Publishers, Inc. 1966Google Scholar
  9. Debas, H. T., Grossman, M. I.: Chemicals bathing the oxyntic gland area stimulate acid secretion in the dog. Gastroenterology 69, 654–659 (1975)Google Scholar
  10. Debas, H. T., Konturek, S. J., Walsh, J. H., Grossman, M. I.: Proof of a pyloro-oxyntic reflex for stimulation of acid secretion. Gastroenterology 66, 526–532 (1974)Google Scholar
  11. Debas, H. T., Walsh, J. H., Grossman, M. I.: Evidence for oxyntopyloric reflex for release of antral gastrin. Gastroenterology 68, 687–690 (1975)Google Scholar
  12. Fox, J. E., Dinda, P. K., Beck, I. T.: Is ethanol toxicity in the jejunum due to osmotic damage. Gastroenterology 72, A-35/1058 (1977)Google Scholar
  13. Grossman, M. I.: Stimulation of secretion of acid by distention of denervated fundic pouches in dogs. Gastroenterology 41, 385–390 (1961)Google Scholar
  14. Grossman, M. I.: Secretion of acid and pepsin in response to distention of vagally innervated fundic gland area in dogs. Gastroenterology 42, 718–721 (1962)Google Scholar
  15. Grossman, M. I.: Neural and hormonal stimulation of gastric secretion of acid. In: Handbook of physiology. Section 6: Alimentary canal., Vol. II (C. F. Code, ed.), pp. 835–863. Washington: American Physiological Society 1967Google Scholar
  16. Johansson, I., Lundell, L., Svensson, S. E.: Inhibition of gastric secretion by atropine in conscious rats. J. Physiol. (Lond.) 217, 723–735 (1971)Google Scholar
  17. Johnson, L. R.: Pepsin output from the damaged canine Heidenhain pouch. Am. J. Dig. Dis. 16, 403–407 (1971)Google Scholar
  18. Johnson, L. R.: Regulation of pepsin secretion by topical acid in the stomach. Am. J. Physiol. 223, 847–850 (1972)Google Scholar
  19. Lowry, O. H., Rosebrough, N. J., Farr, A. L., Randall, R. J.: Protein measurement with Folin phenol reagent. J. Biol. Chem. 193, 265–275 (1951)Google Scholar
  20. Main, I. H. M., Whittle, B. J. R.: The effects of E and A prostaglandins on gastric mucosal blood flow and acid secretion in the rat. Br. J. Pharmacol. 49, 428–436 (1973)Google Scholar
  21. Main, I. H. M., Whittle, B. J. R.: The role of prostaglandins in gastric acid secretion. In: Stimulus-Secretion Coupling in the Gastrointestinal Tract (R. M. Case and H. Goebell, eds.), pp. 147–155. Lancaster: MTP Press Ltd. 1976Google Scholar
  22. Miller, G. L.: Protein determination of large number of samples. Anal. Chem. 31, 964 (1959)Google Scholar
  23. Parsons, M. E.: The antagonism of histamine H2-receptors in vivo and in vitro with particular reference to the actions of cimetidine. In: Proceedings of the Second International Symposium on Histamine H2-receptor antagonists (W. L. Burland and M. A. Simkims, eds.), pp. 13–23. Amsterdam: Excerpta Medica 1977Google Scholar
  24. Puurunen, J., Karppanen, H.: Effects of ethanol on gastric acid secretion and gastric mucosal cyclic AMP in the rat. Life Sci. 16, 1513–1520 (1975)Google Scholar
  25. Sernka, T. J., Jackson, A. F.: Hyperosmotic instillaton of rat stomach. Life Sci. 17, 435–442 (1975)Google Scholar
  26. Sernka, T. J., Jackson, A. F.: Responses to ethanol in rat stomach. Nutr. Rep. Intern. 14, 415–421 (1976)Google Scholar
  27. Soares, E. C., Zaterka, S., Walsh, J.: Acid secretion and serum gastrin at graded intragastric pressures in man. Gastroenterology 72, 676–679 (1977)Google Scholar
  28. Walsh, J. H., Grossman, M. I.: Gastrin. N. Engl. J. Med. 292, 1324–1334 (1975)Google Scholar

Copyright information

© Springer-Verlag 1978

Authors and Affiliations

  • Juhani Puurunen
    • 1
  • Erik Westermann
    • 1
  1. 1.Institut für PharmakologieMedizinische Hochschule HannoverHannover 61Germany

Personalised recommendations