Exocrine Pancreatic Function in Dogs with Denervated Pancreas

Abstract

There is strong evidence that the vagus nerve plays an important role in exocrine pancreatic secretion. In the present study we examined the effect of total extrinsic denervation of the pancreas on exocrine pancreatic secretion to different stimuli in dogs. In the experiments we used the model of the orthotopic autotransplanted dog pancreas as described by Debas et al. Denervation of the gland did not significantly alter water and bicarbonate response to secretin. The dose-response curve of caerulein showed the denervated pancreas as sensitive as the intact gland. However, autotransplantation of the pancreas caused a significant decrease (p < 0.0.5) in protein secretion during intraintestinal L-tryptophan in increasing doses. Furthermore, bicarbonate and protein secretion after food intake was significantly decreased in the denervated pancreas (protein: peak levels 380 mg/15 min and 135 mg/l5 min; bicarbonate: 3.2 mEq/l5 min and 1.4 mEq/l5 min) (p < 0.02). From our data we conclude that the denervated pancreas is as sensitive as the intact pancreas to stimulation by exogenous secretin and caerulein, whereas denervation of the pancreas causes an important influence in the intestinal phase of pancreatic secretion.

Molecular Mechanism of Pancreatic and Salivary Gland Fluid and HCO3−Secretion

“…Plasma secretin in response to a meal reaches only pM levels, which is sufficient to stimulate modest fluid and HCO 3 − secretion in all species. CCK and vagal stimulation further potentiates the secretin-stimulated secretion (134, 216, 460). …”

“…This suggests that other factors, such as CCK and vagal stimulation, synergize with secretin to stimulate ductal fluid and HCO 3 − secretion. A decrease in secretin-evoked HCO 3 − secretion by the cholinergic muscarinic receptors antagonist atropine and by vagal blockade indicates that a vagal cholinergic input is important for postprandial HCO 3 − secretion (134, 216). In addition, exogenous in vivo application of CCK potentiates the secretin-stimulated fluid and HCO 3 − secretion (460).…”

Exocrine pancreatic function during cold blockade of the vagus in chronic experiments on calves

“…The effects of truncal vagotomy have been reported by many authors (Thomas, 1950 for early references; Tankel & Hollander, 1958;Magee, Fragola & White, 1965;Henriksen, 1969;Moreland & Johnson, 1971;Konturek, Becker & Thompson, 1974;Debas, Konturek & Grossman, 1975;Grundy et al 1983). In addition, pancreatic secretion has been studied after complete extrinsic denervation brought about by autotransplantation (Wang & Grossman, 1951;Singer, Solomon & Grossman, 1980;Kohler, Nustede, Barthel & Schafmayer, 1987).…”

Pattern of Postprandial Carbohydrate Metabolism and Effects of Portal and Peripheral Insulin Delivery

“…With this approach, we ensured that the pancreas remained innervated and capable of responding to moment-to-moment changes in arterial glucose concentration. This model also avoids the disruption of exocrine function noted with pancreatic autotransplantation (27). The results in both groups were compared with those in sham-operated animals.…”