Effects of Injecting Excess Arginine on Rat Pancreas

Abstract

When male rats were given single i.p. injection of 500 mg of L-arginine/100 g body weight, the pancreatic acinar cells were destroyed selectively, without any morphological change of Langerhans' islets. As early as 24 hours after the injection, loss of basophilia, zymogen degranulation, and vacuolar and necrotic changes of the acinar cells were noted. After 3 days, fibroblastic activity and atrophy of pancreatic lobuli were evident. Early electron microscopic findings were changes of the endoplasmic reticulum, such as partial dilatation or vacuolation of the cisternae, usually with loss of ribosomes attached to the membrane. The effect of arginine excess may be ascribed to imbalance of amino acids and subsequent to decrease of protein synthesis in the acinar cells. In the course of this study, fat necrosis with marked infiltration of leucocytes was observed in adipose tissues in peripancreatic, epididymal, omental and retroperitoneal areas. This change correlated closely with the marked necrosis of the pancreas. An increase in the level of lipase in the blood was also demonstrated.

Tauroursodeoxycholic acid reduces endoplasmic reticulum stress, trypsin activation, and acinar cell apoptosis while increasing secretion in rat pancreatic acini

“…Histological examinations demonstrate early on morphological changes of the ER during the onset of AP. Gene-profiling studies show significant alterations in ER stress key regulators and in a model of necrotizing pancreatitis all ER stress sensors (PERK, IRE1, and ATF6) become activated, an initiation of downstream signal pathways occurs initiated from the ER (1,17,18,23,25,27). It has also been observed that stimulation of isolated pancreatic acini by different secretagogues can generate an ER stress response (22).…”

“…This includes dilatation or vacuolation of the ER and loss of membrane-bound ribosomes (1,17,25,27). ER changes seem a common reaction of acini to the induction of ER stress (18,23).…”

Effects of probiotics on the severity of experimental acute pancreatitis

“…L-arginine-induced pancreatitis model in rats was firstly described by Mizunuma et al (1984). Tani et al (1990) demonstrated a model of acute necrotizing pancreatitis induced by L-arginine in rats This experimental model has been widely used so far.…”

Therapeutic effects of ellagic acid on L-arginin ınduced acute pancreatitis

“…The increase in these cytokines was hypothesized to occur due to the stimulation of peritoneal macrophages following an intraperitoneal injection of L-arginine or the activation of monocytes/macrophages in severe pancreatic damage 10 . Mizunuma et al 11 have used this property of L-arginine and administered high dose L-arginine intraperitoneally to develop an experimental model for acute pancreatitis. This model is ideal due to its non-invasive and non-invasive nature and the fact that it causes dose-dependent acinar cell necrosis, allowing studies on the pathogenesis of acute pancreatitis.…”