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

Abstract

SUMMARYFour calves were prepared surgically to investigate the exocrine pancreatic function in chronic experiments. Cooling devices were implanted on both vagi for temporary, reversible, thermal blockade of the conductivity in the nerves. Cooling of the vagi caused significant decreases of volume, total protein content and trypsin activity in pancreatic juice. All of these variables recovered to the control level immediately after the cooling. Results presented indicate an important role of vagally driven information on the exocrine pancreatic secretion in calves.

Local versus peripheral blood administration of cholecystokinin‐8 and secretin on pancreatic secretion in calves

“…Supposedly, both long vagal reflexes and short entero-pancreatic reflexes may be involved (Schwartz, 1983). In the present study, we exainined the involvement of vagal nerves using cold vagal blockade technique (Grundy, Hutson & Scratcherd, 1983;Zabielski et al 1990). The interdigestive pancreatic periodic secretion was markedly inhibited by the blockade, indicating that the vagal tone itself or some peptides whose release depends on vagal activity (Schwartz, 1983;Rudnicki, Rigel & McFadden, 1991;Layer, Chan, Go, Zinsmeister & DiMagno, 1993) may be responsible for adjusting the interdigestive function of the exocrine pancreas.…”

“…Cooling started after recording four complete MMCs and was performed as described earlier (Zabielski et al 1990(Zabielski et al , 1992a. During cold vagal blockade, peptides were infused I.A.…”

“…) infusions were made during the phase of duodenal no spiking activity (NSA) associated with the nadir of pancreatic periodic secretion (Zabielski, Onaga, Mineo & Kato, 1993), and simultaneously the concentration of CCK and secretin in peripheral blood was examined. The contribution of vagal supply was studied by employing the reversible cold vagal blockade technique (Zabielski, Podgurniak, Pierzynowski & Barej, 1990).…”

Effect of intraduodenal HCl and soybean extract on pancreatic juice secretion during atropinization and cold vagal blockade in calves

“…However, a CCK-A receptor antagonist inhibited the action of exogenous CCK on the exocrine pancreas without influencing the postprandial response in the dog (Pendleton, Bendesky, Schaffer, Nolan, Gould & Clineschmidt, 1987). In studies in dog, cat, calf and sheep the interdigestive secretion of pancreatic juice was suppressed by various means of vagus blockade and by blockade of the parasympathetic system (Wang & Grossman, 1951;Moreland & Johnson, 1971;Grundy, Hutson & Scratcherd, 1983;Kato, Adachi, Ando, Mineo & Ushijima, 1985;Zabielski, Podgurniak, Pierzynowski & Barej, 1990). However, the interaction between the peptides and the nerves regulating the exocrine pancreas is not fully understood.…”

“…An incision 10 cm long was made in the central part of the neck just dorsal and parallel to the sinistral jugular vein; a cooling device was placed on the left vago-sympathetic trunk for reversing blockade of the vagus by chilling (Zabielski et al 1990). The cooling device comprised a stainless steel tube (1 0 x 0 8 mm) bent into a helix 13-15 mm long with a core diameter of 3 5 mm, two connecting tubes (60 mm long), and an insulating coat of polystyrene.…”