Serum gastrin response to secretin after vagotomy

It is unknown whether the gastrin response to secretin (secretin test) can distinguish hypergastrinemia due to vagotomy from hypergastrinemia due to Zollinger-Ellison syndrome (ZES). Therefore, we measured serum gastrin concentrations basally and in response to intravenous secretin in 13 vagotomized duodenal ulcer patients without preoperative evidence of ZES and in 5 vagotomized patients with ZES. Following secretin, serum gastrin concentrations increased 40 pg/ml or less [mean (± SE) rise 23±3 pg/ml] in the vagotomized patients without ZES. On the other hand, in the patients with ZES serum gastrin increments after secretin ranged from 105 to 1224 pg/ml. Thus, a large (>100 pg/ml) rise in serum gastrin concentrations following secretin in a vagotomized patient should suggest Zollinger-Ellison syndrome and not be attributed to vagotomyper se.Supported by Research Grants AM16816, AM17328 (to the Center for Ulcer Research & Education), and AM17294 from the National Institutes of Arthritis, Metabolism, and Digestive Diseases and a grant from Southwestern Medical Foundation's Kinsler Williamson Brown Fund, Dallas, Texas.     

Secretin and calcium provocative tests in the Zollinger-Ellison syndrome. A prospective study

STUDY OBJECTIVE: To evaluate criteria of positivity for and usefulness of both the secretin and calcium gastrin-provocative tests in patients with the Zollinger-Ellison syndrome. DESIGN: Prospective trial in consecutive patients. SETTING: Referrals to a clinical research center. PATIENTS: Consecutive sample of 80 patients with the Zollinger-Ellison syndrome. INTERVENTION: Kabi-secretin (2 U/kg body weight) given by intravenous bolus and calcium gluconate (10%) (54 mg/kg.h [5 mg/kg.h of calcium]) given by continuous intravenous infusion for 3 hours. Serum gastrin measured at -15, and -1 minutes before, and 2, 5, 10, 15, 20, and 30 minutes after secretin, or every 30 minutes for 3 hours during the calcium infusion. Serum calcium and serum gastrin were measured simultaneously during the calcium infusion. MEASUREMENTS AND MAIN RESULTS: There was no significant difference in the responses of patients with different extents or locations of the tumor, presence or absence of multiple endocrine neoplasia, type-I, or with fasting gastrin less than or greater than 1000 pg/mL. In patients with fasting gastrin of less than 1000 pg/mL, the sensitivity of the secretin test using the criterion of an increase in gastrin of at least 110 pg/mL was 93% (CI, 76% to 99%) and for an increase of 200 pg/mL it was 85% (CI, 66% to 96%), (P greater than 0.05). With the calcium infusion test, the sensitivity using the criterion of an increase of 395 pg/mL was 43%, (CI, 23% to 66%) and for an increase of 50% was 74% (CI, 52% to 90%), (P less than 0.01). The calcium infusion test was positive in 33% of patients with a negative secretin test. With the secretin test, 75% of patients had a positive response by 5 minutes, 95% by 10 minutes, 100% by 15 minutes, and 6% only at 2 minutes. With calcium infusion, patients had positive responses at 120 to 180 minutes. CONCLUSIONS: The secretin test is preferred over the calcium test because of its greater sensitivity and simplicity. The recommended criteria are a 200 pg/mL increase for the secretin test and a 395 pg/mL increase for the calcium test. The calcium test should be reserved for patients having a negative secretin test, gastric acid hypersecretion, and a strong clinical suspicion of the Zollinger-Ellison syndrome.     

Prospective study of the standard meal provocative test in Zollinger-Ellison syndrome

PURPOSE: The purpose of this work was to evaluate the proposed usefulness of a standard meal-stimulated gastrin provocative test in: (1) distinguishing Zollinger-Ellison syndrome (ZES) from antral syndromes; (2) localizing duodenal gastrinomas; or (3) suggesting that patients with multiple endocrine neoplasia type I (MEN-I) may have an increased incidence of antral syndromes. PATIENTS AND METHODS: Seventy-four consecutive patients with ZES referred to the National Institutes of Health were studied prospectively. The extent and location of gastrinomas, acid secretory studies, and the presence or absence of MEN-I were determined and correlated with the results of the gastrin response to standard meal provocative testing. RESULTS: For patients with fasting serum gastrin levels less than 1,000 pg/mL (n = 43), only 44% had a less than 50% increase over the pre-meal value, which is reported to be the typical response in ZES, and 40% had a 50% to 99% increase. Furthermore 16% had a 100% or greater increase, 9% a 150% or greater increase, and 5% a 200% or greater increase, which overlaps with values reported to be characteristic of 98%, 92%, and 46% of patients with antral syndromes. Results did not differ for patients with or without MEN-I, depend on the extent of the gastrinoma (duodenal versus pancreatic gastrinomas), the presence of previous gastric surgery or type of gastric surgery, or for patients with fasting serum gastrin concentrations greater than or equal to 1,000 pg/mL or less than 1,000 pg/mL. studies of four patients before and after resection of the gastrinoma, who prior to surgery had a greater than 100% increase in gastrin secretion after the meal, demonstrated that all patients had a less than 100% increase postoperatively even though no gastric resection was done. CONCLUSIONS: Approximately half of the patients with ZES have a greater than 50% increase in serum gastrin concentration following a standard test meal and one fifth have a 100% or greater increase. Therefore, they cannot be distinguished on this basis from patients with antral syndromes. The increased serum gastrin level after the meal in these patients with ZES appears to be due to the gastrinoma. Furthermore, the current study provides no evidence for the proposals that antral syndromes are more common in patients with MEN-I, that gastric surgery affects the meal response in patients with gastrinomas, or that the meal test is useful in localizing duodenal gastrinomas.     

Comparative study of the value of the calcium, secretin, and meal stimulated increase in serum gastrin to the diagnosis of the Zollinger-Ellison syndrome.

To evaluate the usefulness of provocation tests in the diagnosis of the Zollinger-Ellison (ZE) syndrome stimulation tests with calcium, 15 mg/kg. 3 h, and secretin GIH, 1 U/kg.30 s, were performed in 15 patients with histologically proven or suspected ZE syndrome. Nine of these 15 patients were without previous gastric surgery and in them meal stimulated serum gastrin levels were measured as well. These tests were also performed in normal subjects and in patients with duodenal ulcer, antrectomy, total gastrectomy, and achlorhydria. All tests were considered to be positive if a more than 50% increase in serum gastrin was found. The results indicate that secretin stimulation is the provocation test of first choice in the diagnosis of this syndrome. This test is most valuable for the following reasons: (1) there were few (two out of 15) false-negative test results in ZE patients; (2) there were no false-positive tests in 69 patients without gastrinoma; (3) it was easy and quick to perform; and (4) there were no adverse reactions. The two ZE patients with negative secretin stimulation tests had negative calcium provocation tests as well, in spite of histologically proven gastrinoma. In 11 patients with suspected or proven ZE syndrome and basal serum gastrin levels of less than 1000 pg/ml a rather good correlation (r = 0-841; P less than 0-01) was found between the percental increase in serum gastrin after stimulation by calcium and secretin. Meal stimulated serum gastrin levels are helpful only in patients without previous gastric surgery.     

Serum gastrin in Zollinger-Ellison syndrome: I. Prospective study of fasting serum gastrin in 309 patients from the National Institutes of Health and comparison with 2229 cases from the literature

The assessment of fasting serum gastrin (FSG) is essential for the diagnosis and management of patients with the Zollinger-Ellison syndrome (ZES). Although many studies have analyzed FSG levels in patients with gastrinoma, limited information has resulted from these studies because of their small size, different methodologies, and lack of correlations of FSG levels with clinical, laboratory, or tumor features in ZES patients. To address this issue, we report the results of a prospective National Institutes of Health (NIH) study of 309 patients with ZES and compare our results with those of 2229 ZES patients in 513 small series and case reports in the literature. In the NIH and literature ZES patients, normal FSG values were uncommon (0.3%-3%), as were very high FSG levels >100-fold normal (4.9%-9%). Two-thirds of gastrinoma patients had FSG values <10-fold normal that overlap with gastrin levels seen in more common conditions, like Helicobacter pylori infection or antral G-cell hyperplasia/hyperfunction. In these patients, FSG levels are not diagnostic of ZES, and gastrin provocative tests are needed to establish the diagnosis. Most clinical variables (multiple endocrine neoplasia type 1 status, presence or absence of the most common symptoms, prior medical treatment) are not correlated with FSG levels, while a good correlation of FSG values was found with other clinical features (prior gastric surgery, diarrhea, duration from onset to diagnosis). Increasing basal acid output, but not maximal acid output correlated closely with increasing FSG. Numerous tumoral features correlated with the magnitude of FSG in our study, including tumor location (pancreatic > duodenal), primary size (larger > smaller) and extent (liver metastases > local disease). In conclusion, this detailed analysis of FSG in a large number of patients with ZES allowed us to identify important clinical guidelines that should contribute to improved diagnosis and management of patients with ZES.     

Diagnostic Efficacy of the Secretin Stimulation Test for the Zollinger-Ellison Syndrome: An Intra-Individual Comparison Using Different Dosages in Patients and Controls

Background/Aims: The secretin stimulation test is the principal diagnostic tool to identify Zollinger-Ellison syndrome (ZES). We investigated, by intra-individual comparison, which dose of secretin results in the highest diagnostic efficacy to identify the ZES. Methods: Fifty-seven paired secretin stimulation tests, using both 0.26 μg/kg and 0.78 μg/kg secretin, performed in 13 ZES patients and 12 controls, were analyzed and the findings confirmed in a validation cohort. Results: A gastrin increase of >100 ng/l was found to be the most sensitive and specific criterion for a positive test. Higher gastrin increases after 0.78 μg/kg compared to 0.26 μg/kg secretin contributed to a slightly more sensitive (82.9 vs. 80.5%) but less specific (68.8 vs. 81.3%) test. A validation cohort, with 98 tests using 0.26 μg/kg secretin in 21 ZES patients and 39 controls, provided similar results. In ZES patients with normal fasting serum gastrin levels (<100 ng/l), there was no diagnostic benefit from the use of a higher secretin dose. Conclusions: The 0.26 μg/kg secretin stimulation test has the best diagnostic efficacy for the ZES.     

Secretin-stimulated serum gastrin levels in hyperparathyroid patients from families with multiple endocrine adenomatosis type I.

Twenty-three patients with hyperparathyroidism from six families with the multiple endocrine adenomatosis (MEA) I-syndrome were tested by secretin provocation. In nine cases this led to increases in serum gastrin ranging from 298 to 13 300 pg/ml, whereas the maximum rise in gastrin in the other 14 patients was 32 pg/ml. In all nine patients with marked gastrin responses to secretin, the Zollinger-Ellison syndrome was diagnosed by gastric acid hypersecretion and large increases in gastrin after calcium administration. Six of these nine patients had, at most, minor postprandial rises in gastin and two had demonstrable tumors. In 34 normal subjects, 23 nonaffected members of families with MEA I-syndrome, and 42 patients with various diseases the maximum gastrin response to secretin was 21 pg/ml. We conclude that secretin provocation is helpful in the diagnosis of the Zollinger-Ellison syndrome, especially when basal serum gastrin levels are only slightly elevated.     

Case report: gastrocolic fistula mimicking Zollinger-Ellison syndrome.

Fasting serum gastrin levels greater than 1000 pg/ml are said to establish the diagnosis of gastrinoma in a patient with peptic ulcer disease. The authors observed a patient with recurrent peptic ulcer disease, diarrhea, and a fasting serum gastrin of 1044 pg/ml who had a gastrocolic fistula, not the Zollinger-Ellison syndrome. The provocative tests of gastrin secretion, including secretin infusion and standard meal test, were helpful in ruling out a gastrinoma. This is the first reported association of gastrocolic fistula and hypergastrinemia. The patient demonstrates that the differential diagnosis of markedly elevated serum gastrin should be expanded to include gastrocolic fistula.     

Ovarian carcinoma as a cause of Zollinger-Ellison syndrome. Natural history, secretory products, and response to provocative tests

Zollinger-Ellison syndrome is usually caused by a gastrin-secreting tumor in or near the pancreas. We describe a patient in whom an ovarian cystadenocarcinoma was the cause of the syndrome. The patient presented with a short history of peptic ulceration and development of a large pelvic mass. Investigations demonstrated a basal acid output of 37.8 mEq/h and a maximal acid output of 36.0 mEq/h, and the plasma concentration of gastrin was 830 pg/ml (normal less than 100). Secretin and calcium infusion tests were positive, and a meal test was compatible with Zollinger-Ellison syndrome. Imaging studies demonstrated a normal liver and pancreas but a large cystic right ovarian mass. Resection of the mass resulted in a marked reduction in gastric acid output, a fall in plasma gastrin concentration to normal, negative calcium and secretin tests, and a normal (positive) meal test. Histology of the mass showed it to be a mucinous cystadenocarcinoma. The tumor stained with immunoperoxidase technique was positive for gastrin, and the cyst fluid contained high concentrations of gastrin and calcitonin. One year later, the patient has no biochemical or imaging evidence of tumor. Ovarian, gastrin-producing tumors and pancreatic gastrinomas cannot be distinguished by provocative tests, and negative imaging studies do not exclude a pancreatic tumor. Patients with an ovarian mass and Zollinger-Ellison syndrome should have a bilateral oophorectomy and a careful exploration of the pancreatic area.     

Is the gastrin response to secretin provocation a function of antral G-cell mass? Results in the hypergastrinemia of acid hyposecretion

Some patients with hypergastrinemic achlorhydria may have false-positive secretin provocation as an exaggeration of the normal gastrin response to secretin, presumably related to an increased, or more responsive, antral G-cell mass. To test this hypothesis, we reviewed our experience with secretin provocation in normogastrinemic subjects with presumed normal antral G-cell mass (normal--17, duodenal ulcer--13) and in patients with hypergastrinemia related to changes in antral G-cells (vagotomy--5, hypochlorhydria--7, achlorhydria--10). Basal serum gastrin (mean +/- SEM) was progressively higher for each group; normal (42 +/- 3 pg/ml), duodenal ulcer (53 +/- 4 pg/ml), vagotomy (226 +/- 54 pg/ml), hypochlorhydria (346 +/- 92 pg/ml), achlorhydria (844 +/- 100 pg/ml). On selective analysis of only those with gastrin rises, significant differences (p less than 0.05) in peak gastrin change were found between achlorhydria (93 +/- 21 pg/ml) compared with all other groups and between hypochlorhydria (40 +/- 12 pg/ml) versus normal (6 +/- 1 pg/ml). Linear regression in these responders showed a significant correlation (p less than 0.001) between basal gastrin and peak gastrin change after secretin. There were no false-positive secretin provocation tests, but four achlorhydric patients had gastrin rises greater than 100 pg/ml, whereas no patient in the other categories had rises above 90 pg/ml. Our results support the concept that patients with hypergastrinemic achlorhydria tend to have greater G-cell responsiveness to secretin provocation, which may account for the false-positive results in some such patients.     

Sensitivity, specificity and predictive values of the secretin infusion test in the diagnosis of gastrinoma

From 1974 to 1981, 55 patients, 18 with Zollinger-Ellison syndrome (ZES) histologically confirmed and 37 patients with duodenal ulcer (DU) without pylorostenosis were followed for a minimal period of 5 years. The diagnostic values of a) basal acid output (BAO mEq/h); b) 60 min acid output after secretin infusion, 3 CU-GIH/kg, (MAO-SE mEq/h); c) basal serum gastrin (BSG pg/ml: mean of 4 gastrin determinations) and d) serum gastrin after secretin (SG-SE pg/ml: mean of 4 gastrin determinations during secretin infusion) were calculated. Cut off point values of 100 p. 100 specificity (i. e. no DU patient reached these values) with a positive predictive value of 100 p. 100 (i. e. probability for gastrinoma when this cut off point was attained) were BAO greater than 26 mEq/h, MAO-SE greater than 18 mEq/h, BSG greater than 221 pg/ml, SG-SE greater than 186 pg/ml. The sensitivities of these parameters (i. e. percent of ZES which reached the given cut off point) were respectively (p. 100): 39, 78, 72 and 94. Ranking these parameters according to their own discriminative value expressed by R2 (square correlation coefficient) gave SG-SE, R2 = 0.559; BSG, R2 = 0.508; MAO-SE, R2 = 0.456; BAO, R2 = 0.414. The most discriminative association of 2 variables was SG-SE and MAO-SE (R2 = 0.650). Association of SG-SE, MAO-SE and BAO or BSG (or BAO and BSG) did not increase significantly the discrimination between ZES and DU (R2 = 0.672).     

Secretin-Induced Gastrin Response in the Zollinger-Ellison Syndrome and Chronic Duodenal Ulcer Patients before and after Cimetidine Treatment

A secretin provocative test was performed in 16 patients with chronic duodenal ulcer and in five patients with the Zollinger-Ellison syndrome. In four chronic duodenal ulcer patients a second secretin test was done during acute iv cimetidine administration. There were only slight variations of gastrin compared with the first test. A third test was done on the same four chronic duodenal ulcer patients after 1 month's po cimetidine treatment (1 g/day); gastrin at 0 time was significantly higher than in the previous two tests (p < 0.01). Integrated gastrin response after secretin was significantly lower in the third test than in the first (p < 0.05). In two Zollinger-Ellison syndrome patients treated with 1.0 and 1.4 g/day cimetidine for 3 months, gastrin at 0 time was not markedly increased, whereas compared with the first test gastrin levels were higher at each time after secretin. These data suggest that previous cimetidine treatment does not alter, and may even increase, the diagnostic sensitivity of the secretin test.     

Serum calcitonin levels with calcium loading tests before and after total thyroidectomy in patients with thyroid diseases other than medullary thyroid carcinoma

Calcitonin is a very sensitive tumor marker of medullary thyroid carcinoma (MTC). Patients with MTC have usually very high levels of serum calcitonin that can be used to diagnose the disease. In order to improve diagnostic sensitivity in family members with small MTCs or to evaluate postoperative biochemical cure status, measurement of calcitonin stimulated with combined intravenous calcium gluconate and pentagastrin has been widely adopted; however, gastrin has become unavailable. Currently, a provocative test using only calcium gluconate is performed; however, the standard values for this test have not been reported. We therefore conducted calcium gluconate stimulation tests in 20 patients before and after total thyroidectomy for thyroid diseases other than MTC. Preoperatively, the mean basal calcitonin level was 24.1 pg/mL and increased to 46.9pg/mL after calcium infusion. The ratio of the peak calcitonin level to the basal value ranged from 1- to 5.23-fold, with a mean of 1.94. The ratio was higher than 3-fold in 3 patients. In 2 patients, peak calcitonin levels exceeded 100 pg/mL. Postoperatively, the mean basal level slightly decreased to 21.15pg/mL and the response to calcium stimulation markedly decreased, with the mean ratio decreasing to 1.1-fold (range, 0.86- to 1.73-fold, maximum peak level, 33 pg/mL). Thus, some subjects without MTC show response to the calcium stimulation test up to 5.24 times the ratio and a peak value of 160 pg/mL, suggesting the requirement for judicious judgment for the early diagnosis of MTC in family members; however, after total thyroidectomy, none of the subjects showed an increase of more than 2-fold or a peak value of 33pg/mL, suggesting that responses greater than 2-fold after MTC surgery might be abnormal, indicating the presence of residual tumor.     

Diagnosis of the Zollinger-Ellison syndrome. I: Significance of anamnestic,clinical and laboratory examinations

The authors describe the diagnostic algorithm of Zollinger-Ellison's syndrome which proved useful in the diagnosis of 73 patients with a confirmed diagnosis. They evaluate the diagnostic validity of anamnestic and clinical data, of different examination methods and compare them with experience assembled abroad. For the diagnosis of sporadic gastrinomas the onset of the disease after the age of 40 years is important, the development of serious peptic complications (haemorrhage F-70%, M-59%, perforation M-54%, F-47%) and the presence of watery diarrhoea (41%). As to laboratory parameters they rely on high BAO values (96% > 15 mmol H+/hour and 100% > 5 mmol H+ after gastric resection. Less important is the examination of basal serum gastrin (almost 30% patients have normal or liminal values of BSG--empirically set at 100-150 pg. ml-1). The authors draw attention to the fact that patients with ZES after gastric resections may have BSG values lower than 100 pg/ml (12%). A positive secretin test has a higher validity (rise of SG by 150-200 pg. ml-1 above basal values) positive in 82.2% patients, liminally positive in 11% and negative in 6.3% patients. An even higher diagnostic value was possessed by a BAO/MAO index higher than 0.6 which was positive in 93.4% patients. At present it is not used as pentagastrin is not available. Every year they diagnose 4-6 new cases of ZES which with regard to the number of inhabitants (5 million) places Slovakia along with Denmark and Sweden among the countries with the highest detection rate (0.8-1.2 ZES cases/1 million per year).     

A comparative evaluation of secretin bolus and secretin infusion as secretin provocation tests in the Zollinger-Ellison syndrome

GIH secretin bolus (2 CU/kg) and infusion (3 CU/kg/h) have been randomly compared in 9 ZES patients and 10 age-matched DU patients. Serum gastrin and gastric acid variations were studied before and after either mode of secretin administration in the same individuals. Plasma secretin modifications were monitored in parallel. In both ZES and DU, secretin bolus and infusion induced similar gastrin responses (maximal changes and integrated responses). However, secretin infusion had a greater effect on acid output than bolus: larger inhibition in DU and larger increase in ZES. The additive diagnostic value of gastric acid secretion study during a secretin provocation test, as already reported, favors the use of 3 CU/kg/h secretin infusion over that of 2 CU/kg secretin bolus.     

Calcium and secretin as provocative stimuli in the Zollinger-Ellison syndrome

The effects of calcium and secretin were studied in 8 patients with the Zollinger-Ellison syndrome and 18 patients with duodenal ulcer disease. Intravenous infusion of calcium gluconate produced marked increases in serum gastrin levels in the patients with Zollinger-Ellison syndrome (4,350 +/- 1,625 pg/mg) and very slight increases in the patients with duodenal ulcer disease (140 +/- 49 pg/ml). Secretin given as a single intravenous injection also induced marked elevations in serum gastrin in the group with the Zollinger-Ellison syndrome (4,063 +/- 1,990 pg/ml). By contrast, intravenous secretin resulted in a progressive fall in serum gastrin levels in the duodenal ulcer group (from 119 to 97 pg/mg). These results suggest that both stimuli are very useful dagnostic tools in discriminating between Zollinger-Ellison and non-Zollinger-Ellison patients. The secretin challenge test is felt to be superior to the calcium infusions because it is simpler, safer and very rarely produces false-negative or-positive results.     

Abnormal pancreatic polypeptide release by secretin infusion in Zollinger-Ellison syndrome

In 28 patients with the Zollinger-Ellison syndrome (ZES), 26 studied before and two after tumor excision, and in 26 age-matched control patients with duodenal ulcer (DU), plasma pancreatic polypeptide and serum gastrin concentrations were studied before, during, and after infusion of pure secretin (3 CU/kg/hr). In 21 ZES patients, gastric acid output was simultaneously studied. Fasting pancreatic polypeptide concentrations were over 300 pmol/liter in five of 26 gastrinomas. In DU, secretin caused a nonsignificant increase in plasma pancreatic polypeptide concentration and markedly decreased gastric acid output. In ZES, however, it resulted in a marked increase of both plasma pancreatic polypeptide concentration and gastric acid output. Basal and post secretin pancreatic polypeptide concentrations showed no correlation with gastric acid output, serum gastrin levels, or the age of the subjects, in DU patients as well as in ZES. These concentrations were not different in ZES patients who had a vagotomy compared to nonvagotomized ZES patients. Furthermore, the pancreatic polypeptide response to intravenous secretin was abolished by gastrinoma excision.A portion of this work has appeared in abstract form (Gastroenterology 82:1161, 1982) and was presented at the Annual Meeting of the American Gastroenterological Association, Chicago (Illinois), on May 18, 1982.     

Effect of exogenous gastrointestinal peptides containing the C-terminal tetrapeptide of gastrin on calcium, calcitonin and parathormone serum levels in man

Gastrointestinal hormones containing the C-terminal tetrapeptide of gastrin are involved in calcium homeostasis. The aim of this study was to investigate: 1) the effect of a standard meal (schedule a) and of a duodenal infusion of 5% aminoacid solution (schedule b) on calcium, CT and PTH serum levels in man; 2) the behaviour of these parameters during I.V. infusions of pentagastrin (mcg 1.5/Kg-hour), sincalide (mcg 0.04/Kg-hour) and caerulein (ng 75/Kg-hour) (schedule c). In order to avoid any possible interference by endogenous secretin release, schedule c was performed in 5 patients previously submitted to total gastrectomy. Schedule a and b were studied in 5 healthy volunteers. After a standard meal a slight increase of CT and PTH was measured. Duodenal infusion of aminoacid was followed by hypocalcaemia and slight but constant rise of CT levels, without significant variations of circulating PTH. Pentagastrin, sincalide and caerulein induced a slight but significant hypocalcaemia and a rise of serum CT levels, together with a significant increase of serum PTH. These findings suggest that peptides containing the C-terminal tetrapeptide of gastrin directly affect calcium homeostasis in the absence of secretin release.     

Plaunotol inhibits postprandial gastrin release by its unique secretin-releasing action in humans

Plaunotol, an acyclic diterpene alcohol, is a new antiulcer agent derived from the plau-noi plant and has been reported to stimulate the release of endogenous secretin in humans. We investigated the effect of plaunotol on postprandial gastrin release, comparing it to the effect of exogenous secretin in a physiological dose in eight healthy volunteers. Four sets of experiments were performed in each volunteer: (1) meal alone, (2) meal after intravenous ranitidine (50 mg), (3) meal after oral administration of plaunotol (320 mg) in addition to ranitidine, and (4) meal after ranitidine with simultaneous intravenous infusion of secretin (0.03 CU/kg/hr). The postprandial increase in plasma secretin concentration was significantly reduced by ranitidine, while postprandial gastrin release was markedly exaggerated. Plaunotol in combination with ranitidine significantly increased secretin release and inhibited gastrin release after a meal. Intravenous infusion of secretin resulted in significant suppression of postprandial gastrin release exaggerated by ranitidine. The present study indicates that plaunotol inhibits postprandial gastrin release by its unique secretin-releasing action.This work was supported in part by a grant from the Japanese Ministry of Education.Part of this work was presented at the Annual Meeting of the American Gastroenterological Association, May 13–19, 1989, Washington, D.C., and appeared in abstract form inGastroenterology 96:A469, 1989.     

Intra-operative secretin test for the rapid evaluation of curative operation in a case of Zollinger-Ellison syndrome

The intra-operative measurements of serum gastrin levels and an intra-operative secretin test were carried out as the rapid evaluation of curative operation in a case of Zollinger-Ellison syndrome (ZES). In this case, pre-operative investigations suggested that the tumours were located in the head of the pancreas and the duodenal wall. The surgeon planned a pan-creato-duodenectomy. Serum gastrin levels were reduced after the resection of the head of the pancreas and duodenum, and the secretin test after resection was negative. The surgeon ensured that gastrinomas were resected completely during the operation. The secretin test carried out 1 month post operatively was also negative. The patient has experienced no further complications, to date. This case suggests that intra-operative secretin test is useful for the rapid evaluation of curative operation in case of ZES.