Kara is a 25 year old woman entering the hospital with persistent diarrhea and abdominal pain. an upper gastrointestinal radiologic series suggests the presence of a duodenal ulcer, which is confirmed by endoscopy. kara's basal rate of secretion of gastric hcl is about 12 mmole/hr mmole/hr). kara's serum gastrin is 1145 pg/ml (the normal range is 50 to 150 pg/ml). when kara's gastric juice is removed by nasogastric tube during a 24 hour period, the diarrhea is corrected. kara also has moderate steatorrhea (excess fat in the stool) (the normal range is 1 to 5 what is the role of gastrin on hci secretion?