EFFECTS OF THE AMOUNT AND TYPE OF DIETARY-FAT ON EXOCRINE PANCREATIC-SECRETION IN DOGS AFTER DIFFERENT PERIODS OF ADAPTATION

Mongrel dogs were fed, from weaning to 6 months of age, on one of two 9% lipid diets that differed only in the type of fat content (sunflowe r oil or virgin olive oil) to study their effects on exocrine pancreat ic secretion, in the basal period and in response to food. In addition , the results were compared with those obtained in a previous work per formed by us on dogs adapted for 8 months to diets containing a higher (15%) amount of the same dietary fats to further evaluate the influen ce of the amount of dietary fat and the length of the adaptation perio d. The results from the present study show that both the volume and bi carbonate secreted in the absence of stimuli are unaffected by the qua lity of dietary fat. In contrast, in response to food, the pancreatic juice flow and the bicarbonate output were significantly higher in the group of animals given the sunflower oil diet. The differences seem t o be related with the oleic acid content in the diets and the effectiv eness of this fatty acid in triggering the release of inhibitory pepti des such as pancreatic polypeptide YY. The comparison between the resu lts from our present and previous studies supports the afore-mentioned hypothesis and confirms the existence of a clear influence of the amo unt and type of dietary fat, especially the oleic acid content, upon t he pancreatic response to food, without ruling out a role for the dura tion of the adaptation period.