Intragastric beta-casomorphin(1-7) attenuates the suppression of fat intake by enterostatin.

The current experiments were designed to compare the feeding response to enterostatin and beta-casomorphin(1-7) injected intragastrically. Sprague-Dawley rats with a gastric cannula were allowed to chose from high-fat diet (HF) or low-fat diet (LF) in separate jars. Enterostatin injected intragastrically into overnight fasted rats caused a U-shaped dose-dependent reduction in the intake of the HF diet for the first two hours after infusion but had no effect on the LF intake. beta-Casomorphin(1-7) stimulated the intake of the HF diet but had no effect on the LF diet. Finally, beta-casomorphin(1-7) blocked the inhibitory effect of enterostatin on HF intake in fasted rats.