R.F. Harvey

WHEAT FIBRE AND IRRITABLE BOWEL SYNDROME: A Controlled Trial

Twenty-six patients with irritable bowel syndrome entered a controlled trial of diets with a high or low wheat-fibre content. After 6 weeks on the high-wheat fibre regimen there was significant improvement in symptoms and an objective change in colonic motor activity. No such improvement occurred on the low-fibre regimen. Patients with irritable bowel syndrome should be encouraged to increase their daily intake of wheat fibre.

INHIBITION OF CHOLECYSTOKININ-PANCREOZYMIN RELEASE BY SOMATOSTATIN

To determine the effect of somatostatin on cholecystokinin-pancreozymin (C.C.K.) release, serum-C.C.K. concentrations were measured in normal volunteers after intraduodenal olive oil, with and without a simultaneous intravenous infusion of somatostatin. After instillation of the olive oil there was a rapid rise in serum-C.C.K. (integrated response 19 682+/-5632 pg min ml-1). This rise was completely abolished by somatostatin (integrated response -373+/-330 pg min ml-1, P less than 0-005) and rebound hyper-secretion was seen after the infusion had been stopped. These findings indicate that somatostatin may be involved in regulating C.C.K. release after meals, and suggest a possible explanation for the profound steatorrhoea seen in a patient with a somatostatin-producing tumour.

A RADIOIMMUNOASSAY FOR CHOLECYSTOKININ-PANCREOZYMIN

A sensitive and specific radioimmunoassay for cholecystokinin-pancreozymin (CCK-PZ) has been developed, using rabbit antisera to crude porcine hormone. Highly purified porcine CCK-PZ, labelled with (131)I, and repurified by column chromatography on Sephadex G15, was used as tracer. Separation of free from antibody-bound labelled CCK-PZ was carried out using charcoal, ion-exchange resin, or a double antibody procedure. Non-specific interference with the assay system by serum factors was abolished (as judged by in-vitro and in-vivo recovery studies) by boiling and diluting the serum samples before assay. Ninety-nine per cent pure porcine CCK-PZ (standard), commercial CCK-PZ preparations, caerulein, the C-terminal 8- and 12-amino acid fragments of the CCK-PZ molecule, and endogenous human CCK-PZ all cross reacted in the assay system and showed parallel inhibition curves. No significant cross reaction was found with gastrin, secretin, glucagon, or insulin. The sensitivity of the assay is approximately 5 pg per ml of test solution, which proved adequate for measuring physiological levels of CCK-PZ in peripheral blood in man.The mean immunoreactive CCK-PZ concentration in 50 fasting normal subjects was 60.4 pg per ml. The distribution of individual values was skewed, however, so that the median was much lower (30 pg per ml). Older subjects had higher fasting levels of CCK-PZ than were found in young adults.

Radioimmunoassay of cholecystokinin-pancreozymin.

A sensitive and specific radioimmunoassay for cholecystokinin-pancreozymin (CCK-PZ) has been developed, using rabbit antisera to crude porcine hormone. Highly purified porcine CCK-PZ, labelled with 131I, and repurified by column chromatography on Sephadex G15, was used as tracer. Separation of free from antibody-bound labelled CCK-PZ was carried out using charcoal, ion-exchange resin, or a double antibody procedure. Non-specific interference with the assay system by serum factors was abolished (as judged by in-vitro and in-vivo recovery studies) by boiling and diluting the serum samples before assay. Ninety-nine per cent pure porcine CCK-PZ (standard), commercial CCK-PZ preparations, caerulein, the C-terminal 8- and 12-amino acid fragments of the CCK-PZ molecule, and endogenous human CCK-PZ all cross reacted in the assay system and showed parallel inhibition curves. No significant cross reaction was found with gastrin, secretin, glucagon, or insulin. The sensitivity of the assay is approximately 5 pg per ml of test solution, which proved adequate for measuring physiological levels of CCK-PZ in peripheral blood in man. The mean immunoreactive CCK-PZ concentration in 50 fasting normal subjects was 60·4 pg per ml. The distribution of individual values was skewed, however, so that the median was much lower (30 pg per ml). Older subjects had higher fasting levels of CCK-PZ than were found in young adults.

RADIOIMMUNOASSAY OF LACTOFERRIN IN PANCREATIC JUICE AS A TEST FOR PANCREATIC DISEASES

Lactoferrin, a protein present in pancreatic juice and other exocrine secretions, was measured by radioimmunoassay in pure pancreatic juice obtained by endoscopic cannulation of the pancreatic duct. Lactoferrin concentrations were high in pancreatic juice from patients with chronic pancreatitis, but they were considerably lower in juice from control subjects and patients with carcinoma of the pancreas. The measurement of lactoferrin concentrations in pure pancreatic juice may be useful in the diagnosis of pancreatic diseases.

Effect of Coffee on Human Lower Oesophageal Function

The effect of coffee on lower oesophageal sphincter pressure (LOSP) and intraoesophageal pH was assessed in 10 healthy volunteers, in the fasting state and after a standard Lundh test meal. LOSP was measured by the rapid pull-through technique. Coffee with or without milk has no significant effect on LOSP in the fasting subject. The Lundh meal alone (mean drop = 2.01 cm H2O), or when coffee with (mean drop = 1.80 cm H2O) or without milk (mean drop = 3.47 cm H2O) was taken after it, produced a significant drop in LOSP. Heartburn following coffee does not appear to be due to an effect of coffee on the lower oesophageal sphincter but is more likely due to the effect of a previous meal on sphincter pressure with associated acid reflux.

Trypsin and lactoferrin levels in pure pancreatic juice in patients with pancreatic disease.

Levels of immunoreactive trypsin were measured in pure pancreatic juice obtained endoscopically from 44 patients with suspected pancreatic disease. Patients with pancreatic cancer all had low trypsin concentrations (median 3.6 micrograms/ml, range 0.6--12.0), but those with chronic pancreatitis had very variable levels (median 14.2 micrograms/ml, range 3.2--76.8), showing a considerable overlap with patients without pancreatic disease (median 37.1 micrograms/ml, range 10.4--66.0). When levels of lactoferrin in pancreatic juice were measured, all patients with chronic pancreatitis were found to have much higher levels (all greater than 900 ng/ml) than control subjects or patients with pancreatic cancer (all less than 400 ng/ml). The combined measurement of trypsin and lactoferrin in pure pancreatic juice appeared to be more promising than any other currently available test for the separation of patients with pancreatic cancer from those with chronic pancreatitis.

COLONIC MOTILITY IN PROCTALGIA FUGAX

Intraluminal pressure recordings were obtained from the rectum and sigmoid colon in two patients experiencing attacks of proctalgia fugax. In each patient the pain appeared to result from contractions of the sigmoid colon, and not from spasm of the levator ani, rectal wall muscle, or anal sphincters, all of which have previously been suggested as the source of such pain. Proctalgia fugax therefore appears, at least in some patients, to be an unusual variant of the irritable bowel syndrome, in which pain is referred from the sigmoid colon to the rectum.

Lactoferrin concentration in the parotid saliva of patients with chronic pancreatitis.

Lactoferrin is present in pancreatic juice, and greatly increased concentrations are found in the pancreatic juice of patients with chronic pancreatitis. It is not known whether these high levels of lactoferrin represent a genetically determined defect predisposing to the later development of chronic pancreatitis or are simply a consequence of the disease. In view of the morphological and functional similarities between the pancreatic and parotid glands, we have measured the immunoreactive lactoferrin concentration in pure parotid saliva of 30 patients with chronic calcific pancreatitis, 26 controls, 5 patients with proven pancreatic cancer, 2 patients with Sjögrens disease and 2 patients with chronic recurrent parotitis. No difference in the lactoferrin concentration was detected between control subjects and patients with chronic pancreatitis or pancreatic cancer. Raised levels were found in the 4 patients with parotid gland disease. These findings suggest that increased lactoferrin secretion is confined to the exocrine pancreas in patients with chronic pancreatitis and is thus probably a phenomenon secondary to the disease.

Relationship between changes of serum cholecystokinin-pancreozymin and serum insulin after different stimuli

SummaryThe relationship between changes of serum immuno-reactive cholecystokinin-pancreozymin (CCK-PZ) and serum immuno-reactive insulin has been studied after various stimuli. The oral administration of 5% glucose or magnesium sulphate and the intra-duodenal administration of olive oil were all followed by a rise of serum CCK-PZ. The serum insulin rose after 5% glucose and also showed a small but insignificant rise with olive oil. There was, however, no change of serum insulin after the ingestion of magnesium sulphate suggesting that CCK-PZ in isolation does not stimulate insulin release.