| Abstract: | In the present work, the transported fluid and the tissue content of ATP, ADP and AMP has been evaluated in the jejunum rat intestine which was everted and incubated in vitro both at 28°C and 38°C for 1 h. The energy-rich phosphates have been measured in the tissue at the beginning and at the end of the experiment as well as in vivo. These determinations have been made in the total intestine and in the scraped mucosa. ATP and ADP content are higher in vivo and lower but constant at 28°C in vitro; on the contrary, at 38°C in vitro, the initial and final content of these adenilic nucleotides are both lower than at 28°C. Under all these conditions the AMP content does not vary appreciably.Wet weight to dry weight ratios have been reported for mucosal and submucosal tissues in unincubated and incubated intestines.In some experiments, fluid transport (measured as an actual serosal volume increase) was determined every 20 min during a 1-h incubation. At 28 °C, fluid transport is constant throughout the time of the experiment, but at 38 °C, there is a progressive decrease of the transported fluid.Fluid transport and ATP content of the intestine seem to be directly related. The transport activity which is lower at 38 °C than at 28°C, seems to be due to a low availability of energy-rich phosphates. |
