Smooth muscle inclusion bodies in slow transit constipation

Intestinal Pathology in Patients With Pathogenic ACTG2-Variant Visceral Myopathy: 16 Patients From 12 Families and Review of the Literature

BACKGROUND

Dominant gamma-smooth muscle actin gene (ACTG2) variants cause clinically diverse forms of visceral myopathy. Many patients undergo intestinal resection or biopsy before identification of their genetic defect. The pathology of ACTG2-variant visceral myopathy has not been evaluated systematically.

METHODS

Glass slides, ultrastructural images, molecular genetic reports, and clinical records from 16 patients with pathogenic (15) or likely pathogenic (1) ACTG2 variants were reviewed and compared with surgical specimens from controls (no evidence of a primary myopathy or pseudo-obstruction due to Hirschsprung disease) and published descriptions.

RESULTS

The variable clinical manifestations in our cohort matched those in the literature. Only non-specific light and electron microscopic findings observed in non-myopathic controls were encountered in 13 of 16 patients. The remaining 3 patients harbored hyalinized cytoplasmic inclusions in smooth muscle cells and 1 of them had polyglucosan bodies in the muscularis propria.

CONCLUSIONS

Apart from hyalinized inclusions, which were only observed in 3/16 patients, intestinal pathology in the majority of patients with ACTG2 variants is not indicative of an underlying visceral myopathy. Molecular testing should be considered even when no diagnostic intestinal pathology is identified.

Effects of Xiao Chengqi Formula on Slow Transit Constipation by Assessing Gut Microbiota and Metabolomics Analysis in vitro and in vivo

The Xiao Chengqi (XCQ) formula is a newly constituted traditional Chinese medicine prescription in the treatment of intestinal motility deficiency and is effective in patients with slow transit constipation (STC). XCQ formula was reconstructed based on a "Chengqi" decoction. Astragali Radix, Angelicae Sinensis Radix, and cooked ground Salviae Miltiorrhizae Radix et Rhizoma were added to the prescription to enhance. An STC rat model was constructed and treated with the formula to understand the detailed mechanism by which XCQ promotes intestinal peristalsis. The effects of the XCQ formula on intestinal microflora and metabolic levels and the possible molecular mechanism of its regulation were explored using 16S rDNA sequencing, metabolomics sequencing, and tissue RNA sequencing. The results showed a significant decrease in the abundance of Roseburia spp. in the feces of STC rats, a significant decrease in the content of butyl aminobenzene (BAB) in feces, and an increase in the number of interstitial cells of Cajal (ICC) in the colon of STC rats. Furthermore, in vitro and in vivo experiments revealed that BAB could activate IL-21R on the ICC surface, upregulate the phosphorylation of the downstream molecules STAT3 and ERK, and inhibit loperamide-induced ICC apoptosis. Therefore, the XCQ formula can improve the defecation status of patients with STC by protecting ICC activity, promoting the colonization of Roseburia spp. to promote peristalsis, and increasing the BAB content after metabolism.

Use of high-resolution colonic manometry to establish etiology and direct treatment in patients with constipation: Case series with correlation to histology

BACKGROUND AND AIM

Different clinical treatments are available to treat patients with constipation. We aimed to study the etiology and direct treatment in a case series of patients with constipation by the use of high-resolution colonic manometry (HRCM).

METHODS

High-resolution colonic manometry was used to record the colorectal peristaltic contractions of the entire colon in patients. Based on the results of HRCM, 151 patients with constipation were classified into groups and received different clinical treatment such as a total or subtotal colectomy, local excision, or conservative treatment. Paraffin-embedded samples obtained after resection were studied using hematoxylin and eosin, as well as immunohistochemical staining.

RESULTS

All patients underwent HRCM over 24 h. Based on the amplitude, intensity, and trends in peristaltic contractions recorded by HRCM, we observed 117 patients with slow-transit constipation and 34 with functional outlet obstruction constipation. After an overall evaluation of the results of HRCM and anorectal function, 26, 23, 27, and 75 patients were treated with total colectomy, subtotal colectomy, local excision, and conservative treatment, respectively. Furthermore, histological examination of surgical samples showed vacuolar degeneration of nerve plexuses as well as of the muscularis propria, which also showed fibrosis in its outer layers in patients with constipation.

CONCLUSION

Different types of constipation showed different colonic motility patterns and morphological changes in the colonic wall. HRCM plays an important role in the diagnosis and classification of patients with constipation. Furthermore, HRCM can accurately identify the diseased colonic segments and help to choose the appropriate treatment.

Isobaric tags for relative and absolute quantification-based proteomic analysis that reveals the roles of progesterone receptor, inflammation, and fibrosis for slow-transit constipation

BACKGROUND AND AIM

Progesterone receptor, inflammation, neurotransmitter expression, and fibrosis are involved in slow-transit constipation. The aim of the present study was to examine whether patients with slow-transit constipation have an overexpression of progesterone receptor and serotonin, which may impair the fibrosis of muscularis propria in colorectal wall.

METHODS

High-resolution colon manometry was used to record the colorectal peristaltic contractions of the proximal ascending and sigmoid colon in patients. Protein samples prepared from frozen sigmoid colon tissue and the proximal margin of the ascending colon of four female patients were compared using isobaric tags for relative and absolute quantification labeling technique coupled to 2D liquid chromatography-tandem mass spectrometry analysis. Immunohistochemical staining of progesterone receptor, serotonin, and fibronectin was performed in paraffin-embedded sigmoid colon tissues and the proximal margin of the ascending colon or ileum from 43 patients with slow-transit constipation.

RESULTS

Among these differentially regulated proteins based on isobaric tags for relative and absolute quantification and liquid chromatography-tandem mass spectrometry analysis, 56 proteins involved in the response to progesterone, inflammation, matrix remodeling, fibrosis, and muscle metabolism. Immunohistochemical staining confirmed that there was significantly higher expression of progesterone receptor (t = 19.19, P = 0.000) and serotonin (t = 13.52, P = 0.004) in sigmoid colon than in the proximal margin of the ascending colon and ileum. Progesterone receptor and fibronectin expression in the outer layer of muscularis propria were higher than in the middle layer.

CONCLUSIONS

These results demonstrate that progesterone receptor, along with inflammation and fibrosis, may take part in slow-transit constipation development.

Indian consensus on chronic constipation in adults: A joint position statement of the Indian Motility and Functional Diseases Association and the Indian Society of Gastroenterology

The Indian Motility and Functional Diseases Association and the Indian Society of Gastroenterology developed this evidence-based practice guideline for management of chronic constipation. A modified Delphi process was used to develop this consensus containing 29 statements, which were generated by electronic voting iteration as well as face to face meeting and review of the supporting literature primarily from India. These statements include 9 on epidemiology, clinical presentation, and diagnostic criteria; 8 on pathophysiology; and the remaining 12 on investigations and treatment. When the proportion of those who voted either to accept completely or with minor reservation was 80% or higher, the statement was regarded as accepted. The members of the consensus team believe that this would be useful for teaching, clinical practice, and research on chronic constipation in India and in other countries with similar spectrum of the disorders.

Neuroenteric Staining as a Tool in the Evaluation of Pediatric Motility Disorders

The diagnosis of enteric neuromuscular disorders has come a long way since the first description of an enteric neuropathic disorder by the Danish physician Harald Hirschsprung in 1886. Advances in specialized enteric histopathological staining techniques have made it possible to identify subtle neuropathies and myopathies that cause intestinal motility disorders, from the common and now better understood and relatively easily diagnosed Hirschsprung's disease to the less common and more severe and not well-characterized chronic idiopathic intestinal pseudoobstruction, which continues to present a diagnostic challenge to the gastroenterologist and histopathologist alike. This article will discuss the common gastrointestinal motility disorders and some of the specialized histological stains, such as the relatively common enzyme stain, acetylcholinesterase, used to diagnose Hirschsprung's disease; advanced tinctorial stains, such as Masson trichrome, which may aid in diagnosis of enteric myopathies causing pseudoobstruction; and immunohistochemical stains such as C-Kit or PG 9.5, which may aid in the diagnosis of enteric neuropathies causing pseudoobstruction.

Corpora amylacea in gastrointestinal leiomyomas: a clinical, light microscopic, ultrastructural and immunohistochemical study with comparison to hyaline globules

CONTEXT

Corpora amylacea (CA) are inclusions with starch-like composition that occur in various conditions. We have observed CA in gastrointestinal leiomyomas (GILM) and hypothesised that they differ from intracytoplasmic hyaline globules (HG) of GILM. We aimed to investigate the anatomical distribution, prevalence, staining characteristics and ultrastructural features of CA and compare them with HG of GILM.

DESIGN

Slides from a consecutive series of resected GILM and bland spindle cell tumours were examined for CA and HG. Special stains, electron microscopy and elemental analysis were performed on select leiomyomas.

RESULTS

CA occurred in 13/35 GILM (37%) from the following sites: oesophagus (4/8), stomach (5/7) including one frozen section, small intestine (1/2) and large intestine (3/18), but were not identified in 19 gastrointestinal stromal tumours (12 gastric, 7 small intestinal; p=0.0019), five schwannomas (three gastric, two small intestinal; p=0.154) and 35 non-GILM (p=0.0001). The densities of CA ranged from one per 4-200 mm(2). CA stained intensely with periodic acid Schiff after diastase predigestion (PASD), Alcian blue and ubiquitin, and faintly in peripheral zones for desmin and smooth muscle actin. Ultrastructurally, CA consisted of an electron-dense outer layer and a fibrillar core with scattered particle matter. HG were present in all leiomyomas, but showed variable staining for PASD, negative staining for Alcian blue and ubiquitin, and positive staining for smooth muscle markers.

CONCLUSIONS

CA are a distinctive histological feature of approximately one third of GILM with different composition to HG. These differences may represent divergent degenerative processes or different stages of a single degenerative process over time.

New perspectives in the diagnosis and management of enteric neuropathies

Chronic disturbances of gastrointestinal function encompass a wide spectrum of clinical disorders that range from common conditions with mild-to-moderate symptoms to rare diseases characterized by a severe impairment of digestive function, including chronic pain, vomiting, bloating and severe constipation. Patients at the clinically severe end of the spectrum can have profound changes in gut transit and motility. In a subset of these patients, histopathological analyses have revealed abnormalities of the gut innervation, including the enteric nervous system, termed enteric neuropathies. This Review discusses advances in the diagnosis and management of the main clinical entities--achalasia, gastroparesis, intestinal pseudo-obstruction and chronic constipation--that result from enteric neuropathies, including both primary and secondary forms. We focus on the various evident neuropathologies (degenerative and inflammatory) of these disorders and, where possible, present the specific implications of histological diagnosis to contemporary treatment. This knowledge could enable the future development of novel targeted therapeutic approaches.

Histopathology in gastrointestinal neuromuscular diseases: methodological and ontological issues

Gastrointestinal neuromuscular diseases (GINMDs) comprise a heterogenous group of chronic conditions associated with impaired gut motility. These gastrointestinal (GI) disorders, differing for etiopathogenic mechanisms, pathologic lesions, and region of gut involvement, represent a relevant matter for public health, because they are very common, can be disabling, and determine major social and economic burdens. GINMDs are presumed or proven to arise as a result of a dysfunctioning GI neuromuscular apparatus, which includes myenteric ganglia (neurons and glial cells), interstitial cells of Cajal and smooth muscle cells. Despite the presence of symptoms related to gut dysmotility in the clinical phenotype of these patients, in the diagnostic setting scarce attention is usually paid to the morphologic pattern of the GI neuromuscular apparatus. It is also objectively difficult to collect full-thickness gut tissue samples from patients with GINMDs, because their disease, which can be only functional in nature, may not justify invasive diagnostic procedures as a first-line approach. As a consequence, whenever available, bioptic gut specimens, retrieved from these patients, must be regarded as a unique chance for obtaining relevant diagnostic information. On the basis of these arguments, there is an urgent need of standardized and validated histopathologic methods, aiming at overcoming the discrepancies affecting current approaches, which usually lead to conflicting definitions of normality and hamper the identification of disease-specific pathologic patterns. This review article intends to address current methodological and ontological issues in the histopathologic diagnosis of GINMDs, to foster the debate on how to discriminate normal morphology from abnormalities.

Gastrointestinal neuromuscular pathology in chronic constipation

Some patients with chronic constipation may undergo colectomy yielding tissue appropriate to diagnosis of underlying neuromuscular pathology. The analysis of such tissue has, over the past 40 years, fueled research that has explored the presence of neuropathy, myopathy and more recently changes in interstitial cells of Cajal (ICC). In this chapter, the data from these studies have been critically reviewed in the context of the significant methodological and interpretative issues that beset the field of gastrointestinal neuromuscular pathology. On this basis, reductions in ICC appear to a consistent finding but one whose role as a primary cause of slow-transit constipation requires further evaluation. Findings indicative of significant neuropathy or myopathy are variable and in many studies subject to considerable methodological bias. Methods with practical diagnostic utility in the individual patient have rarely been employed and require further validation in respect of normative data.

Gastrointestinal neuromuscular pathology: guidelines for histological techniques and reporting on behalf of the Gastro 2009 International Working Group

The term gastrointestinal neuromuscular disease describes a clinically heterogeneous group of disorders of children and adults in which symptoms are presumed or proven to arise as a result of neuromuscular, including interstitial cell of Cajal, dysfunction. Such disorders commonly have impaired motor activity, i.e. slowed or obstructed transit with radiological evidence of transient or persistent visceral dilatation. Whilst sensorimotor abnormalities have been demonstrated by a variety of methods in these conditions, standards for histopathological reporting remain relatively neglected. Significant differences in methodologies and expertise continue to confound the reliable delineation of normality and specificity of particular pathological changes for disease. Such issues require urgent clarification to standardize acquisition and handling of tissue specimens, interpretation of findings and make informed decisions on risk-benefit of full-thickness tissue biopsy of bowel or other diagnostic procedures. Such information will also allow increased certainty of diagnosis, facilitating factual discussion between patients and caregivers, as well as giving prognostic and therapeutic information. The following report, produced by an international working group, using established consensus methodology, presents proposed guidelines on histological techniques and reporting for adult and paediatric gastrointestinal neuromuscular pathology. The report addresses the main areas of histopathological practice as confronted by the pathologist, including suction rectal biopsy and full-thickness tissue obtained with diagnostic or therapeutic intent. For each, indications, safe acquisition of tissue, histological techniques, reporting and referral recommendations are presented.

Colonic transit studies: normal values for adults and children with comparison of radiological and scintigraphic methods

The sitz or plastic marker study for colonic transit has been around for many years. It is applicable where an X-ray machine exists, is widely used and is accepted as the gold standard for diagnosing constipation. Recently, radiopharmaceutical methods have been developed. The theme of this review is their possible roles in the assessment of paediatric bowel motility disorders in patients presenting to paediatric surgeons. This review presents data on total and segmental transit in normal adults and children and comparing the two techniques in adults. Reliability and reproducibility are presented. Normative data for colonic transit in adults and children are discussed and parameters for assessing abnormal transit are reviewed. Normal colonic transit takes 20-56 h. Plastic marker studies are more readily accessible, but the assessment may be misleading with current methods. Plastic markers show faster transit than scintigraphy. It is difficult to compare the two techniques because methods of reporting are different. Using scintigraphy, repeatability is good. Separation of normal from slow transit in the ascending colon is apparent at 24 and 48 h, but the determination of transit through the distal colon/rectum in adults may require studies of more than 7 days. In conclusion, plastic marker studies and scintigraphy show similar transit rates in young adults and children. However, scintigraphy has advantages of allowing transit through the stomach and small intestine to be measured and has proved useful in the diagnostic workup of children with intractable constipation.

Clinical presentation and patterns of slow transit constipation do not predict coexistent upper gut dysmotility

BACKGROUND

Slow transit constipation (STC) is associated with upper gastrointestinal tract motor abnormalities in a subset of patients. This could influence the clinical approach, particularly in those rare cases where surgical management is considered.

AIMS

To identify factors that predict proximal gut dysmotility in patients with STC.

METHODS

Esophageal and small bowel motor function were evaluated in 77 patients with STC. Severity and pattern of colonic transit delay, prevalence of a co-existent rectal evacuatory disorder, and type (if present), and duration, and onset of constipation symptoms were compared.

RESULTS

Of the 77 patients studied, 43% exhibited altered motor function in the esophagus and/or small bowel. Frequency of defecation was lower in these patients than in those without upper gastrointestinal dysmotility (0.5 +/- 0.1 vs. 1.3 +/- 0.3 bowel movements/per week, respectively; P = 0.04). Severity and patterns of colonic transit delay and the mechanism associated with the onset of constipation symptoms or with their duration were similar in subjects with or without upper gastrointestinal tract dysmotility. Small bowel but not esophageal motor dysfunction was more frequently associated with a co-existent rectal evacuatory disorder (P = 0.01).

CONCLUSION

Upper gastrointestinal tract dysmotility in patients with STC is frequent, but prediction on the basis of clinical history and characteristics of colonic transit is problematic.

Morphological changes of the enteric nervous system, interstitial cells of cajal, and smooth muscle in children with colonic motility disorders

OBJECTIVES

To evaluate the relation between colonic manometry findings and the colonic enteric nervous system, interstitial cells of Cajal, and smooth muscle morphology.

PATIENTS AND METHODS

Colonic specimens from surgical resections or full-thickness biopsy specimens were assessed from a cohort of children who underwent colonic manometry before surgery. Colonic manometric patterns were subdivided into high-amplitude propagating contractions, low-amplitude propagating contractions, absence of contractions, and low-amplitude simultaneous contractions. Immunohistochemistry was performed to identify abnormalities in the enteric nervous system, interstitial cells of Cajal, and smooth muscle layers.

RESULTS

Study participants included patients with Hirschsprung disease (n = 4), chronic intestinal pseudo-obstruction (n = 1), and idiopathic intractable constipation (n = 8). Thirty-seven ganglionic segments were studied. Abnormalities in myenteric plexus were recognized in segments of all manometry groups, and no differences could be identified when they were compared with segments with high-amplitude propagating contractions. All of the segments showed an abnormal interstitial cells of Cajal plexus, and no statistical difference could be identified between the 4 groups (n = 0.08). Homogeneous expression of smooth muscle actin was observed in all of the segments.

CONCLUSIONS

In this cohort we were unable to classify specific manometric findings as reflective of myopathic or neuropathic abnormalities in patients with motility disorders. Caution should be used when predicting the type of neuromuscular disorder based on colonic manometry.

Pathophysiology of constipation in the older adult

This review provides information on the definition of constipation, normal continence and defecation and a description of the pathophysiologic mechanisms of constipation. In addition, changes in the anatomy and physiology of the lower gastrointestinal tract associated with aging that may contribute to constipation are described. MEDLINE (1966-2007) and CINAHL (1980-2007) were searched. The following MeSH terms were used: constipation/etiology OR constipation/physiology OR constipation/physiopathology) AND (age factors OR aged OR older OR 80 and over OR middle age). Constipation is not well defined in the literature. While self-reported constipation increases with age, findings from a limited number of clinical studies that utilized objective measures do not support this association. Dysmotility and pelvic floor dysfunction are important mechanisms associated with constipation. Changes in GI function associated with aging appear to be relatively subtle based on a limited amount of conflicting data. Additional research is warranted on the effects of aging on GI function, as well as on the timing of these changes.

Comparison of three methods to assess enteric neuronal apoptosis in patients with slow transit constipation

BACKGROUND

The pathophysiological basis of slow transit constipation are scarcely understood. Some recent evidence suggests that increased apoptotic phenomena in the colonic enteric neurons may play a role. However, the best method to assess these phenomena has not been evaluated.

AIMS

To compare three different methods to detect enteric neuronal apoptosis in these patients.

METHODS

Serial colonic tissue sections obtained in 10 patients with intractable slow transit constipation were evaluated with immunohistochemical methods aimed at evaluating apoptotic phenomena: the formamide-MAb method, the TUNEL, and the caspase-3.

RESULTS

The highest yield of apoptotic neurons was obtained by means of the formamide-MAb method, compared to the other two, whereas the lowest yield was observed with the caspase-3.

CONCLUSIONS

The formamide-MAb method, which is able to distinguish apoptosis from necrosis and is not influenced by DNA breaks, may prove useful to assess neuronal apoptotic phenomena in the human enteric nervous system. This represents a relevant method to detect enteric neuronal apoptosis.

Enteric neuropathology of the terminal ileum in patients with intractable slow-transit constipation

Slow-transit constipation is usually considered a colonic motor disorder. However, there is some evidence that abnormalities may be present in locations other than the colon. In particular, several studies have reported abnormal motor activity of the small bowel in these patients. We evaluated the neuropathological aspects of the terminal ileum in patients with slow-transit constipation to see whether abnormalities are present that may explain an abnormal motility of the small intestine. Specimens of the terminal ileum were obtained from 16 female patients (age range, 42-76 years) with slow-transit constipation undergoing surgery for intractable symptoms. Fifteen age- and sex-matched controls were used for comparison. Histologic and immunohistochemical evaluation of the myenteric plexus and the smooth muscle of the proximal ileal resection margin was carried out by means of hematoxylin and eosin, trichrome and periodic acid-Schiff stain, neuron-specific enolase, S-100, CD117, CD34, anti-alpha-actin, desmin, and vimentin antibodies. The patient group displayed a significantly reduced number of glial cells, compared with controls, in both the submucosal and the myenteric plexus. Only 1 of the 3 populations of interstitial cells of Cajal (that associated with the deep muscular plexus) was decreased in patients. No differences were found between patients and controls concerning ganglia neurons, fibroblast-like cells, enteric neurons, apoptotic phenomena, and smooth muscle. Patients with slow-transit constipation display neuropathological abnormalities of the terminal ileum to a lesser extent than those we previously found in the colon, which might explain the abnormal motor aspects sometimes found in these patients.

The role of glial cells and apoptosis of enteric neurones in the neuropathology of intractable slow transit constipation

BACKGROUND

Idiopathic slow transit constipation is one of the most severe and often intractable forms of constipation. As motor abnormalities are thought to play an important pathogenetic role, studies have been performed on the colonic neuroenteric system, which rules the motor aspects of the viscus.

AIMS

We hypothesised that important neuropathological abnormalities of the large bowel are present, that these are not confined to the interstitial cells of Cajal and ganglion cells, and that the previously described reduction of enteric neurones, if confirmed, might be related to an increase in programmed cell death (apoptosis).

PATIENTS AND METHODS

Surgical specimens from 26 severely constipated patients were assessed by conventional and immunohistochemical methods. Specific staining for enteric neurones, glial cells, interstitial cells of Cajal, and fibroblast-like cells associated with the latter were used. In addition, gangliar cell apoptosis was evaluated by means of indirect and direct techniques. Data from patients were compared with those obtained in 10 controls.

RESULTS

Severely constipated patients displayed a significant decrease in enteric gangliar cells, glial cells, and interstitial cells of Cajal. Fibroblast-like cells associated with the latter did not differ significantly between patients and controls. Patients had significantly more apoptotic enteric neurones than controls.

CONCLUSION

Severely constipated patients have important neuroenteric abnormalities, not confined to gangliar cells and interstitial cells of Cajal. The reduction of enteric neurones may in part be due to increased apoptotic phenomena.

Normal aspects of colorectal motility and abnormalities in slow transit constipation

Human colonic motility is a relatively difficult topic to investigate. However, the refinement of manometric techniques in recent years enabled us to study both the proximal and distal segments of the viscus. The present paper reviews our knowledge about normal aspects of colorectal motility in man and the abnormalities found in slow transit constipation (STC), one of the most frequent and difficult to treat subtypes of constipation. An internet-based search strategy of the Medline and Science Citation Index was performed using the keywords colon, colonic, colorectal, constipation, slow transit, motility, rectal, rectum in various combinations with the Boolean operators AND, OR and NOT. Only articles related to human studies were used, and manual cross-referencing was also performed. Most of colonic motor activity is represented by single nonpropagated contractions, rarely organized in bursts; this activity is maximal during the day, especially after waking and following meals. In addition, a specialized propagated activity with propulsive features is detectable, represented by high- and low-amplitude propagated contractions. In the severe form of constipation represented by the slow transit type, the above motor activity is completely deranged. In fact, both basal segmental activity (especially in response to meals) and propagated activity (especially that of high amplitude) are usually decreased, and this may represent a physiologic marker of this disorder. Human colonic motor activity is quite a complex issue, still only partly understood and investigated, due to anatomic and physiological difficulties. In recent years, however, some more data have been obtained, even in proximal segments. These data have helped in elucidating, although only in part, some pathophysiological mechanisms of chronic constipation, and especially of the STC subtype.

A systematic analysis of polyglucosan bodies in the human gastrointestinal tract in health and disease

Polyglucosan inclusion bodies have been described in smooth muscle of the gastrointestinal tract of aged dogs, and rarely in association with enteric dysmotility in humans. We have systematically examined the human small and large bowel for the presence of such inclusions in health and motility disorders. Systematic, blinded, dual observer analysis of colonic and ileal tissue from patients (n=80, age 20-92 years) undergoing large bowel resections for non-dysmotile conditions, principally neoplasia was performed, as well as retrospective review of all intestinal tissues referred for specialist histochemistry from patients undergoing surgery for motility disorders. All sections were stained with haematoxylin and eosin and periodic acid-Schiff stains. No polyglucosan bodies were identified in any specimen without dysmotility, regardless of age, but were a feature of 4/104 patients with diverse severe gastrointestinal motility disorders. In contrast to dogs, polyglucosan bodies are not a feature of normal ageing in human gastrointestinal smooth muscle but, in accord with previous suggestions, are seen in rare cases of human gut dysmotility. The significance of this difference is unclear.

Effect of areca on contraction of colonic muscle strips in rats

AIM: To investigate the effects of areca on the contractile activity of isolated colonic muscle strips in rats and mechanism involved.

METHODS: Each strip (LMPC, longitudinal muscle of proximal colon; CMPC, circular muscle of proximal colon; LMDC, longitudinal muscle of distal colon; CMDC, circular muscle of distal colon.) was suspended in a tissue chamber containing 5 mL Krebs solution (37 °C), bubbled continuously with 950 mL•L⁻¹ O₂ and 50 mL•L⁻¹ CO₂. The mean contractile amplitude (A), the resting tension (T), and the contractile frequency (F) were simultaneously recorded on recorders.

RESULTS: Areca dose dependently increased the mean contractile amplitude, the resting tension of proximal and distal colonic smooth muscle strips in rats (P < 0.05). It also partly increased the contractile frequency of colonic smooth muscle strips in rats (P < 0.05). The effects were partly inhibited by atropine (the resting tension of LMPC decreased from 0.44 ± 0.12 to 0.17 ± 0.03; the resting tension of LMDC decreased from 0.71 ± 0.14 to 0.03 ± 0.01; the mean contractile amplitude of LMPC increased from -45.8 ± 7.2 to -30.5 ± 2.9; the motility index of CMDC decreased from 86.6 ± 17.3 to 32.8 ± 9.3; P < 0.05 vs areca), but the effects were not inhibited by hexamethonium (P > 0.05).

CONCLUSION: Areca stimulated the motility of isolated colonic smooth muscle strips in rats. The stimulation of areca might be relevant with M receptor partly.