The influences of acute hyper- and hypocalcemia and of calcitonin on exocrine pancreatic function in man

Abstract

The influences of acute changes of the serum calcium and of ealeitouin (CT) on the exoerine pancreatic function have been studied in man. During stimu. lation with secretin and choleeystokinin-panereozymin (CCK-PZ) Ca++-glucolactobionate, Na,-EDTA, porcine and human synthetic CT were infused i.v. Hypercalcemia provoked an increase of enzyme secretion under unstimulated and secretin stimulated conditions; however, in the case of CCK-PZ administration enzyme output was not altered. EDTA-hypocalcemia inhibited pancreatic secretion during secretin as well as during CCK-PZ infusions. CT doses above 2 MRCU caused a decrease of enzyme secretion during simultanous secretin/CCK-PZ administration by about 70---80% of the initial value without decreasing serum Ca++; doses of 0.5 MRCU and less were without effect. In none of the experiments bicarbonate secretion was affected. The results show important changes of the pancreatic enzyme secretion during acute hyper-and hypocalcemia, while calcitonin exerts an inhibitory effect daring normocalcemia.

Duodenal Calcium in Chronic Pancreatitis: Is It of Diagnostic Value?

“…We found that acute hypercalcemia in creased pancreatic enzyme secretion and thus confirmed earlier observations [5,7,8]. Sim ilar to the response to CCK-PZ, calciuminduced chymotrypsin secretion was mark edly reduced in chronic pancreatitis due to impaired secretory capacity.…”

Calcitonin and exocrine pancreatic secretion in man: inhibition of enzymes stimulated by CCK-pancreozymin, caerulein, or calcium no response to vagal stimulation

“…enzyme secretion stimulated by CCK-PZ, while acutely induced hypercalcaemia increased enzyme secretion during continuous infusion of secretin (Hotz et al, 1973;Goebell et al, 1973b).…”

Human calcitonin stimulates salivary amylase output in man.

“…The stimulatory effect of hCT on salivary amylase (Schmidt et al, 1971;Hotz et al, 1973). This observation, therefore, is an example of the fundamental functional difference between pancreas and salivary glands despite their close histological resemblance.…”

“…For example, CT inhibits pentagastrin stimulated lower oesophageal sphincter pressure (Waldeck et al, 1973); oral and parenteral CT inhibit gastric secretion Hesch et al, 1972;Becker etal., 1974;Ziegler etal., 1974); hCT depresses fasting serum gastrin in patients with medullary carcinoma of the thyroid and those with peptic ulcer (Go et al, 1972;Becker et al, 1974); it inhibits contraction of the gallbladder (Winckler et al, 1973); it stimulates small bowel motility (Gray et al, 1973); and it inhibits glucose stimulated release ofinsuline from the endocrine pancreas (Ziegler et al, 1972). All these effects including those on the exocrine pancreas (Schmidt et al, 1971;Hotz et al, 1973) and our own observations on salivary glands have been achleved with doses of hCT which produce serum concentrations about 100 times higher than those measured in normal man. Therefore, it is unlikely that the gastrointestinal effects of hCT are of major physiological importance.…”