Effect of hypocalcaemia and lipid peroxidation on experimental acute pancreatitis.

It has been studied whether hypocalcaemia increased the mortality rate of experimental acute pancreatitis in the rat, and whether lipids injected into the pancreas underwent peroxidation, damaging thereby the gland. Prolonged hypocalcaemia was induced by bilateral parathyrodectomy and intensified by a calcium-deficient diet. Parathyroidectomy significantly decreased also arterial blood pressure. Three hours after their intraductal injection, both 0.2 ml sunflower oil and 5 mg trypsin significantly decreased arterial blood pressure in the non-parathyroidectomized animals and so did 5 mg trypsin in the parathyroidectomized ones; sunflower oil decreased the blood calcium level below 5 mg/100 ml in parathyroidectomized rats fed a calcium-deficient diet. No differences were found in the mortality rates of nonparathyroidectomized normocalcaemic rats and parathyroidectomized hypocalcaemic ones, or in the extent and gravity of pancreatic injury and in the extent of fat tissue necrosis at 3 and 24 hours after the intraductal injection of 0.2 ml sunflower oil or 5 mg trypsin. Sunflower oil, oleic acid and linoleic acid injected by retrograde way into the pancreas in 0.2 ml volume each induced extensive danage to the acinar parenchyma, while liquid paraffin failed to do so. Among these agents, only linoleic acid increased, as a sign of lipid peroxidation, malonaldehyde concentration in the pancreatic tissue. Linoleic acid injected into the submaxillary salivary gland in 0.1 ml volume induced extensive tissue damage, while sunflower oil, oleic acid failed to do so.