Comparison of the myoelectrical activity of the lateral and J-shaped ileal reservoirs.

Ileal myoelectrical activity was studied in ten 10-cm J-shaped and ten lateral ileal reservoirs (IR) in rabbits. Electrodes and a strain gauge were placed on both ileal segments of the reservoirs as well as the proximal and distal ileum entering and leaving the reservoirs. In three additional rabbits without reservoirs (controls), electrodes and a strain gauge were sutured to the distal ileum in a similar manner. Myoelectrical activity was recorded as (1) short spike burst complexes (SSBC) lasting greater than 25 seconds but less than three minutes, and (2) long spike burst complexes (LSBC) lasting more than three minutes. SSBC propagated through the lateral IR two weeks after its construction and were synchronous with intestinal contraction. In contrast, SSBC did not become organized or propagate distally through the J-shaped IR until eight weeks after reservoir construction. LSBC occurred infrequently in control rabbits and in those after construction of the J-shaped and lateral IRs. Propagation of LSBC in control rabbits was synchronous with prolonged propulsive intestinal contraction. In both the J-shaped and lateral reservoirs, LSBC occurred randomly and did not propagate from proximal to distal ileum through the IR until three months after reservoir construction. The frequency and duration of LSBC remained diminished for the J-shaped IR at three months when compared with the lateral IR. It is concluded that the return of normal propulsive activity occurs earlier in the lateral iso-peristaltic IR than in the J-shaped IR but that both are effective at three months.(ABSTRACT TRUNCATED AT 250 WORDS)