A model for simultaneous study of pressure and electric events in the rabbit sphincter of Oddi and duodenum

Human sphincter of Oddi motility and cholecystokinin response following liver transplantation

The reported incidence of sphincter of Oddi dysfunction following orthotopic liver transplantation has ranged from 3% to 7%. If sphincteric dysfunction is unrecognized, therapy may be inappropriate; when recognized, extensive surgery may be required. To prospectively identify patients with sphincteric dysfunction, we performed sphincter of Oddi motility studies through the t-tube tract three months after transplantation. Baseline sphincter motility and response to intravenous cholecystokinin were evaluated. The results of 10 subjects are reported; nine had normal basal sphincter pressure (16 +/- 5.8 mm Hg), and all had normal frequency (3.6 +/- 1/min), amplitude (86 +/- 31 mm Hg), and duration (4.5 +/- 1 sec) of phasic contractions. One subject had an elevated basal pressure (47 mm Hg). All, including the subject with elevated basal pressure, demonstrated a normal response to intravenous cholecystokinin with significant inhibition of phasic contraction frequency and amplitude. We demonstrate that simultaneous studies of the sphincter and duodenum can be obtained via the t-tube tract, providing the opportunity for prospective evaluation of sphincteric function. We conclude that sphincter of Oddi function usually remains normal following liver transplantation with choledochocholedochostomy.

Rabbit sphincter of Oddi has a certain autonomy: characteristic features

Simultaneous recordings of electromyography and manometry were obtained from rabbit sphincter of Oddi (SO) and duodenum. Three different patterns of activity were observed in SO and in duodenum: 1) a low-amplitude (less than 3 cm H2O) pattern of background oscillations with 2) superimposed high-amplitude (4-20 cm H2O) contractions and 3) occasional complex contractions consisting of an elevation of the basal pressure with superimposed smaller contractions. A certain SO autonomy was evident: 57.6% of SO pressure peaks could not be assigned to any duodenal activity. The distribution of SO pressure peak amplitudes could not be described by a simple normal distribution. The distribution of SO pressure peak amplitudes with concomitant duodenal activity differed from the overall distribution (p less than 0.001). Whereas a substantial part of SO pressure peaks greater than 4 cm H2O had no or low-amplitude corresponding duodenal pressure activity, duodenal pressure peaks greater than 4 cm H2O almost invariably were associated with SO pressure peaks. It is concluded that rabbit SO does possess a certain autonomy, but at the same time a close functional connection exists between the two compartments.

Rabbit sphincter of Oddi and duodenum are regulated by slow waves with a common basic-mode activity

Simultaneous recordings of pressure and slow-wave activity were obtained from the sphincter of Oddi (SO) and the duodenum in anesthetized rabbits. Histographic analysis of the recordings was performed when the following criteria were fulfilled: 1) slow waves must be present in the EMG recordings from both compartments; and 2) only pressure recordings with sufficient pressure activity (greater than 50 peaks in 10 min) would be considered. Of 12 animals fulfilling the criteria for histographic analysis of 4 channels, a common basic-mode activity was found in all channels in 9 animals (75%). Of three animals fulfilling the criteria for histographic analysis of three channels, a common basic-mode activity was seen in all channels in all animals (100%). A correlation between the amplitude of the slow waves and the amplitude of the elicited pressure peaks in the SO was significant at a 5% level or better in 12 animals (80%). In some of the animals episodes of low-amplitude pressure activity was observed in the SO, occurring synchronously with slow waves devoid of spike activity. It is concluded that rabbit SO and duodenum are paced by slow waves with a common basic-mode activity in most animals. Slow waves may not only be the chief determinant of the contractile rhythm but may also have a certain influence on the force of the individual SO contractions. It is suggested that slow waves per se may be able to mediate contractile activity.

Functional and morphological relationships between the feline main pancreatic and bile duct sphincters

To analyze the relationships between the bile duct and main pancreatic duct sphincters, the resistance to flow through these sphincters was studied simultaneously with perfusion techniques in anesthetized cats. Basal flow resistance was higher in the pancreatic sphincter than in the bile duct sphincter. The pressure in one duct system was not affected by the flow in the other. The muscular activities in the sphincters were usually well coordinated. Distention of the upper biliary tract or the pancreatic duct system reduced the flow resistance in both sphincters. Cholecystokinin-8 (0.01 micrograms), duodenal distention, and sublingual glyceryl trinitrate (0.4 mg) also relaxed both sphincters, whereas secretin in a dose that induced pancreatic secretion had no consistent effect. Morphine increased flow resistance in both systems. These functional studies indicate that the 2 sphincters share smooth muscle fibers at the level where the flow resistances arise, and there are thus no grounds for separate control of the sphincters. There was no evidence of a functionally common sphincter ampulla. The conclusions drawn from the manometric results were supported by morphological findings in this study.