Intestinal, pancreatic, and hepatic effects of gastrointestinal hormones in a total parenteral nutrition rat model

IV Hypertonic Glucose Stimulates the Exocrine Pancreas in Rat

BACKGROUND

Pancreatic atrophy and dysfunction resulting from parenteral nutrition (PN) may be explained by several mechanisms; one of the important factors is the nutrient in the circulation, which affects the pancreatic growth and secretion. The effect of nutrients on the pancreatic exocrine still has controversies. The aim of the present study is to better understand the effect of i.v. glucose on the exocrine pancreas stimulated by cholecystokinin during the parenterally fed condition.

METHODS

Two mixed solutions consisting of 30% and 50% glucose, respectively, were used. Thirty male Sprague-Dawley rats were randomly divided into 5 groups, including a control group; a freely fed group received cholecystokinin; 2 groups were infused with 30% and 50% glucose, and a group was infused with 50% glucose with cholecystokinin. The body weight and pancreatic contents were measured after 10 days.

RESULTS

The body weight in all groups was increased but lower than in the freely fed rats. I.v. glucose caused a decrease in the pancreatic weight, the amount of the pancreatic protein and DNA, and the level of amylase but elevated the level of trypsin in all treated groups. The enzymes were elevated after infusion of cholecystokinin with glucose, but they were lower than in freely fed animals with cholecystokinin. Compared with 30% glucose, 50% glucose elevated the level of amylase but did not affect the level of trypsin.

CONCLUSIONS

I.v. glucose results in atrophy of the exocrine pancreas, elevates the amylase in pancreas, but suppresses the stimulatory effect of cholecystokinin on the exocrine pancreas.

Total parenteral nutrition attenuates cerulein-induced pancreatitis in rats

OBJECTIVES

Our aim was to determine if total parenteral nutrition (TPN)-induced pancreatic atrophy and Hsp70 expression attenuates cerulein-induced pancreatitis in rats.

METHODS

Rats were randomized to a 7-day course of saline infusion plus a semipurified diet or TPN, with or without an intravenous cerulein injection or vehicle on day 7, and killed 1 or 6 hours after the injection. Based on a pilot study, 1 hour was the primary time point. Pancreatic atrophy was determined by mass, protein, and DNA contents. Pancreatic heat shock protein 70 (Hsp70) expression was measured by Western analysis. Histological examination of the pancreas assessed for edema, inflammation, vacuolization, and apoptosis. Serum amylase activity was measured using the Phadebas assay. Pancreatic trypsinogen activation was measured using a fluorometric substrate assay.

RESULTS

The saline-infused rats fed orally gained significantly more weight than TPN rats. The TPN decreased the pancreatic mass and protein content and the protein-DNA ratio and increased the pancreatic DNA content compared with the saline. The TPN increased the pancreatic Hsp70 expression by 91% compared with the saline. The TPN reduced the cerulein-induced pancreatic histological edema, the vacuolization, and the inflammation compared with the saline. The increase in the serum amylase level after cerulein injection was significantly attenuated, and trypsinogen activation was reduced in TPN animals compared with the saline group.

CONCLUSIONS

Lack of luminal nutrients with a 7-day course of TPN provides moderate protection against cerulein-induced pancreatitis in rats.

Enteral feeding for high-risk neonates: a digest for nurses into putative risk and benefits to ensure safe and comfortable care

Enteral feeding is considered a relatively safe method of providing nutritional support to high-risk neonates. Nonetheless, there are associated risks, which can be classified as follows: factors to consider before initiating enteral feeding; feeding tube placement; delivery of milk feedings; and gastrointestinal, environmental, and technical factors. For each classification, this article highlights adverse consequences and synthesizes the literature for evidence-based nursing practice recommendations, which are summarized in the "Conclusion" section. Many gaps are identified in the research literature, and directions for future research are described to ensure safe and comfortable care for high-risk neonates receiving enteral feedings.