The effect of reduced maternofetal blood flow on the development of fetal pancreatic acinar cells and enzymes.

It has been noted that from days 18 to 22 (birth) during the second intrauterine period of morphogenesis of the rat pancreas the accumulation of enzymes increases dramatically. We studied the effect of altered maternofetal blood flow on the development of the rat pancreas during the critical second period. Our studies indicate that during pancreatic cytodifferentiation, reduction in maternofetal blood flow not only reduces the weight of the pancreas (68% of control) and diminishes the total activities of enzymes but that the changes in specific activities of the enzymes do not appear to be coordinate. The specific activities of amylase decreased to 59,000 units from the control value of 103,000 units (P less than 0.01) and lipase decreased to 4000 units from a control value of 7350 units (P less than 0.001). In contrast, the specific activities of trypsin (ogen), chymotrypsin (ogen) and (pro)-carboxypeptidase A and B are not changed. These results suggest that reduction in maternofetal blood flow caused a selective decrease of fetal rat amylase and lipase during the third trimester of gestation.