Defective release of eosinophil chemotactic factor from peripheral leukocytes in patients with chronic urticaria

Release of eosinophil chemotactic factor (ECF) and histamine was studied peripheral leukocytes of 16 normal and 12 ragweed allergic volunteers and compared to 15 patients with chronic urticaria. Cells were exposed to varying concentrations of anti-IgE or to ragweed antigen E in the case of allergic donors. Twelve of 15 patients with chronic urticaria showed defective release of ECF as well as histamine, while almost all normal and all allergic donors were able to release larger quantities of both mediators. Since the eosinophil is thought to have a modulating effect at sites of inflammation induced by anaphylactic mechanisms, the defective release of a factor attracting these cells may explain the persistence of symptoms in chronic urticaria.

Effects of ethinyl estradiol and phenobarbital on bile acid synthesis and biliary bile acid and cholesterol excretion

Bile acid synthesis calculated from respiratory (14)CO2 derived from the catabolism of [26 or 27-(14)C]cholesterol to bile acids in rats with intact enterohepatic circulations decreased 50% after 5 days of ethinyl estradiol treatment (5 mg per kg per day). Maximal derepressed bile acid synthesis, measured as biliary bile acid excretion after bile acid pool depletion, was also reduced 50% by ethinyl estradiol treatment. Because ethinyl estradiol did not alter biliary cholesterol excretion, bile contained less bile acid relative to cholesterol. Hepatic bile acid concentration was not increased by ethinyl estradiol treatment. Because the inhibitory effect of ethinyl estradiol on bile acid synthesis required 5 days of treatment it is concluded that bile acid synthesis probably was not reduced by negative feedback repression of 7alpha-hydroxylase, the rate-limiting enzyme in bile acid synthesis, which has a half-life of 2 to 3 hr. During the first 14 hr after bile duct cannulation, before bile acid pool depletion, ethinyl estradiol-treated rats excreted less than one-half as much bile acid and the same amount of cholesterol as controls. The bile acid to cholesterol ratio was therefore decreased. Rats treated simultaneously with phenobarbital and ethinyl estradiol excreted significantly more bile acid than rats treated with ethinyl estradiol alone, but biliary cholesterol excretion was not increased. The proportion of biliary bile acid relative to cholesterol was thereby restored to the control value. In contrast, after 14 hr of bile drainage and depletion of the bile acid pool, rats treated with ethinyl estradiol and those treated with phenobarbital-ethinyl estradiol excreted the same amount of bile acid. Thus, when phenobarbital is administered with ethinyl estradiol, it increases the bile acid pool size and biliary bile acid excretion, but it does not increase bile acid synthesis. The increase in pool size and biliary bile acid excretion might be due to the phenobarbital-induced increase in ileal absorption of bile acids.

Allergy to insect sting. III. Allergenic cross-reactivity among the vespid venoms

Recent reports have indicated that venoms may be more beneficial than whole body extracts for the diagnosis and treatment of Hymenoptera sensitive patients. These studies were undertaken to determine the cross-reactivity among the vespid venoms. Eighteen patients who were anaphylactically sensitive to vespid venoms were studied using in vitro leukocyte histamine release. The results (venom concentration for 50% histamine release) were analyzed by linear regression analysis; there was no allergenic cross-reactivity between any of the venoms, except for a modest association between yellow hornet and white hornet venom. In spite of this result 13 of the 18 patients studied were sensitive to three or four of the venoms tested. There is no clear explanation for this observation, but it suggests the existence of multiple major allergens in the vespid venoms, some of which are cross-reactive. Since immunotherapy with inappropriate proteins may lead to the development of IgE and the possibility of clinical sensitivity and since the majority of patients were not sensitive to all venom preparations, we suggest that appropriate diagnostic studies be carried out before the institution of therapy.

Defective histamine release in chronic urticaria

Histamine release from peripheral blood leukocytes challenged with anti-human IgE was studied in patients with chronic urticaria and nonatopic controls. 19 of 23 controls, but only 6 of 20 patients, released over 20% of the total available leukocyte histamine. The response to anti-IgE concentrations of 1.66, 0.33, 0.066, and 0.013 mug antibody N/ml was significantly lower in patients than in controls. Serum IgE levels were significantly higher in the patients but total histamine content of about 10(7) leukocytes was not. Deuterium oxide (D2O) greatly increased histamine release (in both groups), indicating that the anti-IgE interacted with the basophils of urticaria patients. Passive sensitization of leukocytes with biologically active IgE was achieved in both patients and control subjects whose cells responded to anti-IgE, but was not achieved in either patients or control subjects whose cells were nonresponsive to anti-IgE challenge. 125I-anti-IgE autoradiographic studies revealed no obvious quantitative abnormality in the amount of basophil-bound IgE in chronic urticaria patients. Ionophore stimulation of aliquots of the same leukocytes used for anti-IgE challenge demonstrated that the urticaria patients' basophils were capable of releasing normal amounts of histamine. Leukocyte cyclic AMP levels in the two groups were not significantly different either in base-line levels or in responsiveness to stimulation with isoproterenol. These data indicate that chronic urticaria patients have a (acquired?) defect in leukocyte histamine release that occurs after the anti-IgE-IgE interaction, but before the actual (second-stage) release process, and that is comparable to the phenomenon of desensitization.

Measurement of bile acid synthesis by 14CO2: the metabolism of propionyl CoA

The relationship between 14CO2 evolution from the catabolism of [26 or 2714C] cholesterol to bile acids was studied in rats with biliary fistulae. When equal quantities of [26 or 2714C] cholesterol and [414C] cholesterol were administered, there was a significant linear relationship between 14CO2 expiration in the breath and [414C] bile acid excreted in the bile. Bile acid synthesis calculated as the ratio of 14CO2: molar specific activity of biliary cholesterol correlated highly with biliary bile acid excretion in the bile acid depleted rat. Phenobarbital, a known inducer of gamma-amino levulenic acid formation from succinyl CoA did not alter the relationship between the 14CO2 estimation of bile acid synthesis and biliary bile acid excretion, indicating that the relationship between [26 or 2714C] cholesterol side chain cleavage and 14CO2 formation was not altered. Phenobarbital, however, did cause a reduction in bile acid synthesis measured by 14CO2 evolution and by biliary bile acid excretion. The 14CO2 method underestimated bile acid excretion. 8.7% in untreated and phenobarbital treated rats respectively. Since 11% of the radioactivity which was expired as 14CO2 was isolated as bile acids, radioactivity cleaved as [1 or 314C] propionyl CoA may enter cholesterol-bile acid biosynthesis resulting in the underestimation of bile acid synthesis. To test whether radioactivity from propionyl CoA enters steroid biosynthesis [114C] propionate and [214C] propionate were given to untreated biliary fistula rats and the biliary lipids excreted in 60 hours were analyzed. Incorporation of radioactivity into cholesterol and bile acids was greater after the administration of [214C] propionate than after [114C] propionate than after [114C] propionate, suggesting that radioactivity from propionyl CoA may enter steroid biosynthesis by metabolic events in which the methylene and carboxyl carbon atoms are differentiated. Although the use of 14CO2 expiration from [26 or 2714C] cholesterol catabolism underestimates the rate of bile acid synthesis, it should have many applications because of the constant relationship between 14CO2 formation and cholesterol side chain cleavage.

In vivo effect of bile salts and cholestyramine on intestinal anaerobic bacteria

In vitro studies have shown that some bile salts inhibit the growth of intestinal bacteria. We investigated the possibility that bile salts might have a similar action in vivo in the ileum by performing serial anaerobic cultures and bile salt analyses on postprandial ileal fluid obtained anaerobically via intestinal tube. Five subjects were studied under control conditions, and after a 1-week course of orally administered cojugated bile salts in a dose shown to increase the bile salt pool. Three of the subjects were also studied after a 1-week course of cholestyramine. The numebr of ileal anaerobic microorganisms decreased significantly after both bile salt and cholestyramine treatment. Ileal bile salt concentrations were generally high (mean 9.2 mM) and did not change significantly after either bile salt or cholestyramine treatment. The results of this study are unexplained. Although it is possible that bile salts play a role in the regulation of small intestinal anaerobic flora, the lack of a relationship between ileal bile salt concentration and population levels of anaerobic organisms is puzzling and raises further questions about such a role for bile salts.

Persistent hypotension and intestinal infarction in a patient with primary amyloidosis

A patient with primary amyloidosis and the nephrotic syndrome had diarrhea and gastrointestinal bleeding probably due to intestinal ischemia. He died with extensive intestinal infarction. The infarction was most likely caused by decreased splanchnic perfusion secondary to the chronic hypotension of the nephrotic syndrome and to amyloid deposition within the walls of the small blood vessels supplying the gut. Although amyloidosis was suspected prior to death, a fixation artifact probably prevented the correct antemortem biopsy diagnosis.

The treatment of retained stones in the common bile duct with sodium cholate infusion

Six patients with stones retained in the common bile duct after cholecystectomy and common duct exploration were treated by intraductal infusion of a sodium cholate solution. In the five patients whose stones were between the T-tube and the duodenum the treatment was successful within a few days. A stone became transiently impacted in the ampullary region soon after beginning therapy in three patients and produced mild pancreatitis in two. The only failure was in a patient whose stone was between the T-tube and the liver.

Factors affecting plasma clearance of (14C) cholic acid in patients with cirrhosis

1. Clearance of [14C]cholic acid from the systemic circulation was studied in six normal subjects and eight patients with biopsy-proven hepatic cirrhosis. In both groups, during fasting, the curve for disappearance of radioactivity from the serum during the first 100 min after [14C]cholic acid injection was double-exponential in form. During the early phase, clearance was significantly more rapid, and concentrations of conjugated and free bile acid were significantly lower, in normals than in cirrhotics.

2. Radioactivity disappeared from the systemic circulation of normals within 3 h, and neither intravenous cholecystokinin nor the ingestion of food influenced serum radioactivity. Almost all cirrhotic patients had ‘spontaneous’ rises in serum radioactivity, which began approximately 2 h after [14C]cholic acid injection. Cholecystokinin or food given 4–8 h after [14C]cholic acid administration, produced rises. Continuous aspiration of duodenal juice markedly reduced these rises. Reinfusion of duodenal juice into the upper intestine was followed by a rise in serum radioactivity.

3. All rises were due, almost exclusively, to conjugated bile acids.

4. Impaired bile acid clearance in cirrhotics may result from inefficient hepatic extraction of bile acids, increased leakage of conjugated bile acids from hepatic cells and shunting from portal to systemic circulations. The latter factor is probably responsible for elevated, fluctuating, plasma bile acid concentrations in cirrhotic patients.

Fecal excretion of bile acids: a new technique for studying bile acid kinetics in patients with ileal resection

The fecal elimination and enterohepatic circulation of bile acid was studied in 11 patients. 10 patients with varying degrees of ileal disease or resection and 1 patient with pancreatic insufficiency and no ileal disease. A new technique was employed which involved the nearly simultaneous administration of cholic acid-(14)C and a nonabsorbable marker. (51)CrCl(3). Each individual stool specimen was collected for 36-96 hr and analyzed separately. Assay of the radioactivity of each isotope allowed the accurate determination of an excretion rate for both cholic acid and (51)Cr. The difference between these rates was used to calculate an absorption coefficient for cholic acid. In addition, bile acid concentration measured by the steroid dehydrogenase technique, and the water content of each stool was determined. THE PATIENTS WERE DIVIDED INTO GROUPS DEPENDING UPON HOW MUCH SMALL INTESTINE WAS RESECTED OR DISEASED: six patients with less than 100 cm of ileal resection or disease (group A), and five patients with more than 100 cm of ileal disease or resection (group B). The (51)Cr excretion rate was similar in the two groups, but cholic acid-(24)C excretion rates were significantly more rapid in group B than in group A. The cholic acid absorption coefficient was essentially normal in the patient with pancreatic insufficiency, moderately decreased in group A patients, and extremely low or zero in group B patients. It was inversely related to the length of intestine diseased or resected. Daily fecal bile acid excretion was normal to twice normal in group A patients and 2-8 times normal in group B patients. In all patients with ileal disease or resection, there was a direct correlation between fecal bile acid, fecal mass, and fecal water. Each millimole of additional bile acid in the stool was associated with an increase in stool water of 11 moles (P < 0.01). These studies show that the kinetics of bile acids in the enterohepatic circulation can be accurately studied in patients with extensive ileal resection. The regular relationship between fecal bile acid and fecal mass and water suggests, but does not prove, a critical role of bile acid in determining stool water.

Protein starvation and the small intestine. 3. Incorporation of orally and intraperitoneally administered 1-leucine 4,5-3H into intestinal mucosal protein of protein-deprived rats

Weanling rats were fed diets which contained either no protein or 27% protein. In one experiment after 23-35 days both groups were given l-leucine-4,5-(3)H either intragastrically or intraperitoneally and then sacrificed 24 hr later. In a second experiment animals were given these diets for 21 days and sacrificed 3, 6, or 12 hr after either intragastric or intraperitoneal administration of the labeled leucine. In both experiments the intestinal mucosa of proximal and distal segments of the small intestine was scraped, weighed, the protein concentration measured, and the specific activty of the mucosal protein was determined. The wet weight of the mucosa and the protein concentration of the mucosa were significantly greater in the control animals than in the protein-depleted animals. The mucosal protein per 100 g of body weight was the same in the protein-deprived and the control groups. The specific activity of the intestinal mucosal protein was higer in the protein-deprived animals than in the control animals. In the protein-deprived animals the proximal segment incorporated more radioactive amino acid into mucosal protein than did the distal segment at 3, 6, 12, and 24 hr after the amino acid was given by mouth. A similar difference was found between the proximal and distal segments of the control animals 6 hr after oral adminisstration of l-leucine-(3)H. On the other hand, when the l-leucine-(3)H was given intraperitoneally to both groups of animals there was no difference between proximal and distal small intestine. These findings suggest that intestinal mucosal protein can be synthesized directly from intraluminal amino acids, especially during protein deprivation, and that endogenous intraluminal protein might be important in the nutrition of the small intestinal mucosa.

Bile salt malabsorption in regional ileitis, ileal resection and mannitol-induced diarrhea

Fecal bile salt excretion was studied in healthy volunteers, patients with regional ileitis, and patients with ileal resection. 10 muc of carboxyl-(14)C-cholic acid was given orally. Stools and urine were collected daily for 5-10 days, the bile salts extracted, and the radioactivity assayed. Urinary excretion was negligible. All patients with ileal resection excreted bile salts in the feces significantly faster than controls, and five of the six excreted 50% of the radioactivity within 24 hr. Their mean intestinal transit time was 5.6 hr compared to 26 hr for the controls. Two of the three patients with regional ileitis excreted bile salts almost as rapidly as patients with ileal resection. Vitamin B(12) absorption was also defective in those patients, but the intestinal transit time was not decreased. To study the effect of rapid intestinal transit on bile salt excretion, four of the control subjects were given orally 1200 ml of 10% mannitol for 7 days, and the labeled cholic acid excretion rate was again studied. The mean intestinal transit time was markedly shortened, mild steatorrhea developed, and the fecal bile salt excretion rate increased slightly. It is concluded that ileal resection and ileal disease are major factors and rapid intestinal transit is a minor factor in causing excessive fecal bile salt loss. The relevance of bile salt wastage to lipid malabsorption is unknown because of insufficient information about compensatory jejunal absorption, maximum rate of hepatic bile salt synthesis, and the minimum necessary intraluminal concentration of conjugated bile salt.