Summary
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.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Altamirano, M.: Action of solutions of reduced somotic concentration on the dog gastric mucosa. Am. J. Physiol. 216, 25–32 (1969a)
Altamirano, M.: Action of concentrated solutions of non-electrolytes on the dog gastric mucosa. Am. J. Physiol. 216, 33–40 (1969b)
Anson, M. L., Mirsky, A. E.: The estimation of pepsin with haemoglobin. J. Gen. Physiol. 16, 59–63 (1932)
Assouline, G., Leibson, V., Danon, A.: Stimulation of prostaglandin output from rat stomach by hypertonic solutions. Eur. J. Pharmacol. 44, 271–273 (1977)
Bergegardh, S., Olbe, L.: Gastric acid response to antrum distention in man. Scand. J. Gastroenterol. 10, 171–176 (1975)
Bynum, T. E., Johnson, L. R.: Stimulation of human pepsin output by topical hydrochloric acid. Am. J. Dig. Dis. 20, 607–612 (1975)
Cieszkowski, M., Konturek, S. J., Obtulowicz, W., Tasler, J.: Chemical stimulatory mechanism in gastric secretion. J. Physiol. (Lond.) 246, 143–157 (1975)
Davenport, H. W.: Physiology of the digestive tract, pp. 112–113. Chicago: Year Book Medical Publishers, Inc. 1966
Debas, H. T., Grossman, M. I.: Chemicals bathing the oxyntic gland area stimulate acid secretion in the dog. Gastroenterology 69, 654–659 (1975)
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)
Debas, H. T., Walsh, J. H., Grossman, M. I.: Evidence for oxyntopyloric reflex for release of antral gastrin. Gastroenterology 68, 687–690 (1975)
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)
Grossman, M. I.: Stimulation of secretion of acid by distention of denervated fundic pouches in dogs. Gastroenterology 41, 385–390 (1961)
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)
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 1967
Johansson, I., Lundell, L., Svensson, S. E.: Inhibition of gastric secretion by atropine in conscious rats. J. Physiol. (Lond.) 217, 723–735 (1971)
Johnson, L. R.: Pepsin output from the damaged canine Heidenhain pouch. Am. J. Dig. Dis. 16, 403–407 (1971)
Johnson, L. R.: Regulation of pepsin secretion by topical acid in the stomach. Am. J. Physiol. 223, 847–850 (1972)
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)
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)
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. 1976
Miller, G. L.: Protein determination of large number of samples. Anal. Chem. 31, 964 (1959)
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 1977
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)
Sernka, T. J., Jackson, A. F.: Hyperosmotic instillaton of rat stomach. Life Sci. 17, 435–442 (1975)
Sernka, T. J., Jackson, A. F.: Responses to ethanol in rat stomach. Nutr. Rep. Intern. 14, 415–421 (1976)
Soares, E. C., Zaterka, S., Walsh, J.: Acid secretion and serum gastrin at graded intragastric pressures in man. Gastroenterology 72, 676–679 (1977)
Walsh, J. H., Grossman, M. I.: Gastrin. N. Engl. J. Med. 292, 1324–1334 (1975)
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Puurunen, J., Westermann, E. Osmotic stimulation of pepsin secretion in the rat. Naunyn-Schmiedeberg's Arch. Pharmacol. 304, 63–67 (1978). https://doi.org/10.1007/BF00501378
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00501378