الفهرس | Only 14 pages are availabe for public view |
Abstract The present work is carried out to demonstrate the effects of nitric oxide on the motility of isolated segments of different parts of the digestive system in rabbits. These segments are obtained from the lower esophagus, gastric antrum, duodenum and distal colon. They are suspended in organ bath containing aerated Kreb’s Henseleit-buffer solution pH 7.4 at 37Co. Motility is recorded using isotonic transducer and an oscillograph. The present study includes the following experiments: group I experiments: are carried out to study the effect of basal NO production on the basal motility of each segment of GIT. This is done by the addition of L-NAME 10-4 M, which blocks NOS. group II experiments: are carried out to study the effect of basal NO production on the motility after adding ACh (1μg %) or adrenaline (20μg %). group III experiments: are carried out to study the effect of the increased production of NO, by L-arginine 10-3 M, on the basal motility. group IV experiments: are carried out to study the effect of the increased production of NO, by L-arginine 10-3 M, on the motility after adding ACh (1μg %) or adrenaline (20μg %). The results of the present work show that: In group I: - L-NAME significantly increases the tone of contractions in all the studied segments, but decreases the amplitude of contractions except in gastric strips. |