I. Dodd Wilson

Irritable colon and depression

Abstract Numerous attempts have been made to relate specific emotional conflicts to colonic symptoms in the irritable colon syndrome. Depression has been described as an accompaniment of the illness. This paper investigates the relationship between irritable colon and depression using self-rating symptom scales and the Zung Self-Rating Depression Scale. Thirty-one subjects were followed for two months in a double-blind study employing a tricyclic antidepressant and an inactive placebo. The study demonstrates the frequency of depression in patients with the syndrome; it shows a clearly positive treatment effect with placebo alone for both depressive symptoms and gastrointestinal complaints, and suggests that tricyclic antidepressant therapy results in moderately greater improvement in symptoms than does treatment with placebo alone.

IMMUNOGLOBULINS WITHIN HUMAN SMALL-INTESTINAL PANETH CELLS

Human duodenal, jejunal, and ileal samples obtained at necropsy and by peroral and surgical biopsy, were studied by light microscopy using the unlabelled antibody enzyme method for imunocytochemical staining of lysozyme and immunoglobulins. Paneth cells contained IgA and IgG, but not IgD IgE, or IgM. Staining intensity indicated that IgA and IgG were present in amounts greater than in other epithelial cells. There was pronounced variation in the immunoglobulin content of Paneth cells. Rat Paneth cell containing IgA and lysozyme and are capable of the phagocytosis and degradation of microorganisms. These observations suggest that human Paneth cells may have similar functional capabilities.

Cholinergic Stimulation of Immunoglobulin A Secretion in Rat Intestine

This study was undertaken to assess a possible role for cholinergic agents in the regulation of intestinal immunoglobulin A secretion. Intestinal loops, constructed in anesthetized rats, were perfused with phosphate buffered normal saline. Immunoglobulin A concentrations were measured by radioimmunoassay. When compared with the effect of normal saline in the same rats, intravenous injection of pilocarpine, 10 mg/kg, increased immunoglobulin A concentrations in perfusates from ileal loops (p less than 0.001). Qualitatively similar results were obtained with muscarine and bethanechol, from jejunal and colonic loops, and from unanesthetized rats. Immunoglobulin A concentrations increased four- to eightfold during maximal cholinergic stimulation. Atropine, 250 micrograms intravenously, completely blocked the effect of pilocarpine on immunoglobulin A secretion (p less than 0.005), and also inhibited basal intestinal immunoglobulin A secretion for 40 min after injection. As determined on 10%-40% sucrose density gradients, much of the immunoglobulin A secreted after cholinergic stimulation sedimented in the 11S range. These data indicate that intestinal secretion of immunoglobulin A is stimulated by the muscarinic effect of cholinergic agonists, and suggest that basal secretion of immunoglobulin A may be influenced by the parasympathetic nervous system.

Occurrence of Specific Secretory immunoglobulin A in Bile After Inoculation of Giardia lamblia Trophozoites Into Rat Duodenum

We studied the appearance of specific secretory immunoglobulin A (IgA) antibody in bile after inoculation of live Giardia lamblia trophozoites into rat intestine. Serial bile specimens collected before and after inoculation of trophozoites were assayed for IgA antibodies by indirect immunofluorescence. Secretory IgA antibodies to Giardia lamblia were first detected in bile at 3 days after inoculation, remained elevated through 12 days, and then returned to control levels. Positive immunofluorescence of trophozoites for IgA was observed at bile titers of 1:80 to 1:160, whereas control biles were usually negative at dilutions of 1:10 or less. Scanning electron microscopic examination of Giardia in conjunction with immunocytochemistry revealed IgA antibodies bound to the flagella and surfaces of the trophozoites including the adhesive disk. These data demonstrate the occurrence of a secretory IgA immune response directed against surface antigens of Giardia lamblia trophozoites in the rat.

A quantitative morphometric analysis of rat ileal Thiry-Vella fistulae.

Controversy exists regarding the mechanism and degree of mucosal alterations occurring in defunctionalized segments of intestine. This study compares the results of a quantitative analysis of mucosal components, including Paneth cells and immunocytes, between in-continuity and defunctionalized (Thiry-Vella) segments of rat ileum. The micrometer component quantitator was used for the light microscopic morphometric analysis. Intracellular lysozyme and IgA were identified employing the unlabeled antibody enzyme immunohistochemical staining technique. The vol% of the ileal mucosal components of animals from the control group and from the in-continuity segments of the experimental group were comparable. Analysis of the Thiry-Vella fistulae, however, revealed a statistically significant decrease in the vol% of columnar epithelial cells and increase in the vol% of lysozyme-containing Paneth cells and interstitium of the lamina propria. Since Thiry-Vella fistulae are neurovascularly intact, mucosal alterations imply a causal relationship to interaction with chyme. The data suggest that chyme has both a stimulatory (on the columnar epithelium) and suppressive (on the the Paneth cell population) effect. The vol% of IgA-containing Paneth cells and the percentage of the lamina propria represented by IgA-containing immunocytes were also substantially decreased. Normally secretory IgA is the immunoglobulin of highest concentration intraluminally and among immunocytes within the lamina propria, presumably in response to local antigenic stimulation. The presence of immunoglobulin within Paneth cells may reflect the phagocytosis of immunoglobulin complexed antigens. The data suggest that the degree of local antigenic stimulation is decreased in Thiry-Vella fistulae.

A Rational Approach to GI Bleeding Emergencies

A plan for treatment of acute gastrointestinal hemorrhage is spelled out in terms of the way the problem presents and evolves for the physician. In this approach, efforts to locate the source and underlying cause of bleeding are undertaken only after shock has been treated and normal blood volume restored. A definitive therapeutic regimen is then developed according to the particular needs of the individual patient.