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At least 757 records · Page 42Linked to original sources
PubMed1998

Regional quantitation of preprodynorphin mRNA in guinea pig gastrointestinal tract.

The endogenous opioid peptide dynorphin has been shown by immunochemical studies to be widely distributed in the gastrointestinal tract. The aim of this study was to determine basal levels of preprodynorphin (ppDyn) mRNA in different regions of the gastrointestinal tract of the guinea pig. A modified sensitive and specific solution hybridization RNase protection assay was used to quantitate ppDyn mRNA, with confirmation by gel analysis of the RNase protected hybrids and PCR amplified cDNA. This method combines high sensitivity and sufficient throughput to analyze large number of samples in a single assay. Low but measurable amounts of ppDyn mRNA were detected in fundus, duodenum, jejunum, ileum, cecum, and rectum. The rectum contained significantly more ppDyn mRNA than the stomach, small bowel, and cecum. The muscularis/myenteric plexus layer of both ileum and rectum contained a higher concentration of ppDyn mRNA per microg total RNA compared to the mucosa/submucosa/submucosal plexus. However, a greater absolute amount of ppDyn mRNA (80-85%) localized to the mucosal layer. The greater absolute amount of ppDyn mRNA in the mucosal layer may indicate the presence of dynorphin in the endocrine cells of the mucosa.

Animals↗
PubMed1994

Frequency of stress lesions of the upper gastrointestinal tract in paediatric patients after cardiac surgery: effects of prophylaxis.

BACKGROUND: Stress lesions of the upper gastrointestinal tract are well recognised in adult patients in intensive care. There are no controlled studies of the incidence of these lesions and the effects or side effects of prophylactic treatment in high risk paediatric patients. METHODS: 79 paediatric patients in intensive care were studied prospectively after operation for congenital heart disease. All patients had at least one endoscopic examination. The first 36 patients were not given prophylactic medication: later 43 children were treated randomly either with pirenzepine (n = 21) or with famotidine (n = 22). Gastric and tracheal secretions were taken daily for culture in those patients given prophylactic medication. RESULTS: Severe inflammation or ulceration of the upper gastrointestinal tract was less common in those patients who were given prophylactic medication (18% v 44%). Prophylactic treatment did not, however, reduce the total incidence of postoperative stress lesions: it shifted the severity of these changes towards mild lesions and reduced the incidence of ulcerations from 25% to 2%. None of the patients developed a pneumonia caused by an organism previously isolated from the stomach. CONCLUSIONS: The incidence of stress lesions in children after cardiac surgery resembles that in high risk adult patients. Children in intensive care after cardiac surgery should be treated prophylactically with famotidine or pirenzepine until they can be fed by mouth.

Adolescent↗
PubMedDate not supplied

Mucosal production of complement C3 and serum amyloid A is differentially regulated in different parts of the gastrointestinal tract during endotoxemia in mice.

The effect of endotoxemia and sepsis on mucosal production of the acute-phase proteins complement component C3 and serum amyloid A (SAA) was studied in mice. In addition, the role of the proinflammatory cytokines tumor necrosis factor-alpha, interleukin (IL)(-1)beta, and IL-6 on mucosal C3 and SAA production was examined. Endotoxemia was induced by the subcutaneous injection of 250 microg/mouse of lipopolysaccharide. Control mice were injected with corresponding volumes of sterile saline solution. Sepsis was induced by cecal ligation and puncture, and sham-operated mice served as controls. Endotoxemia resulted in increased mucosal C3 levels in all parts of the gastrointestinal tract examined, from the stomach to the colon, with the most pronounced effects noticed in the proximal gastrointestinal tract. The influence of endotoxemia on mucosal SAA production was more differentiated with increased levels noted in the jejunum and ileum, and no changes seen in gastric and colonic mucosa. Sepsis resulted in similar changes in mucosal C3 and SAA levels as seen in endotoxemic mice, except that SAA levels were increased in colonic mucosa of septic mice. Among the cytokines, IL(-1)beta resulted in the most pronounced changes in mucosal acute-phase proteins. The increase in C3 and SAA levels in the mucosa of the small intestine during endotoxemia was partially blocked by IL(-1) receptor antagonist. The results suggest that endotoxemia is associated with increased mucosal C3 production in different parts of the gastrointestinal tract and increased SAA production in the mucosa of the small intestine. Mucosal acute-phase protein synthesis may, at least in part, be regulated by IL(-1)beta.

Analysis of Variance↗
PubMed2004

[Complication of NSAIDs treatment in gastrointestinal tract].

Nonsteroidal anti-inflammatory drugs (NSAIDs) are the common medicaments administered to relieve pain and other inflammation symptoms. Apart from indisputable advantages, the use of these can cause the undesired complications especially concerning gastrointestinal tract. Some of them could be serious. The most disturbing is that some of the gastrointestinal tract damage done by NSAIDs is asymptomatic. It is imperative to identify risk factors in patients who use NASIDs and to undertake the appropriate preventive measures. Nowadays it is possible to implement prophylaxis and to avoid complications and to improve the safety profile. In this paper authors presented conditions under which the complications of use of NSAIDs could appear and the possible prophylactic measures that could be undertaken. The most common is the use of proton pump inhibitor.

Anti-Inflammatory Agents, Non-Steroidal↗
PubMedDate not supplied

Autoradiographic localization of octylonium bromide binding sites in the rat gastrointestinal tract.

The anatomical localization of the binding sites of the spasmolytic drug octylonium bromide (OB) in the rat gastrointestinal tract was analyzed by use of light microscope autoradiography. The drug was visualized after in vitro incubation of frozen sections of the gastrointestinal tract with a 10 nM concentration of 14C-OB and after in vivo injection into the ascending, transverse, descending and sigmoidal portions of the colon. In vitro experiments demonstrated the specific accumulation of 14C-OB within the colonic and rectal smooth muscle. In contrast, no specific binding of the radiolabeled drug was noticeable in the stomach or in the small intestine. In vivo intracolonic injection of 14C-OB showed a significant accumulation of the drug in the colonic musculature 2 min after administration. The predominant localization of 14C-OB in the colonic and rectal musculature could explain its effectiveness in suppressing the amplitude and frequency of colonic contractions and in controlling the irritable bowel syndrome.

Animals↗
PubMed1992

New concepts in imaging of the gastrointestinal tract in children.

This article highlights some of the significant recent advances in imaging of the pediatric gastrointestinal tract that have occurred over the last decade. The current roles of the newer imaging modalities, including ultrasound, computed tomography, and magnetic resonance imaging, are discussed and illustrated. Particular emphasis is given to antenatal evaluation, suspected gastric outlet obstruction, inflammation, and other causes of the acute abdomen. Enhancements in fluoroscopic techniques are outlined, including the use of the newer contrast agents as well as air reduction of intussusception. Continued good communication between the pediatric radiologist and pediatric surgeon is vital to improve the care to children with disorders of the gastrointestinal tract.

Abdomen, Acute↗
PubMed2006

Novel KIND1 gene mutation in Kindler syndrome with severe gastrointestinal tract involvement.

BACKGROUND: Kindler syndrome (online Mendelian Inheritance in Man No. 173650) is an autosomal recessive genodermatosis characterized by acral trauma-induced blistering that improves with age and by progressive poikiloderma in later life. Other clinical features include photosensitivity, webbing of the fingers and toes, nail dystrophy, periodontal disease, and mucosal alterations. Aside from esophageal or anal stenosis, gastrointestinal tract involvement seems to be rare in Kindler syndrome. Recently, mutations in the KIND1 gene that encodes for the membrane-associated protein kindlin-1 have been identified. Kindlin-1 links the actin cytoskeleton to the extracellular matrix and is supposed to have cell-signaling functions owing to different functional domains. In particular, a domain with high homology to 4.1/ezrin/radixin/moesin (FERM) proteins is closely related to the sequences of talin that mediate integrin binding and therefore may play a role in integrin-dependent processes such as cell growth, differentiation, and apoptosis. OBSERVATION: Complete loss of this multifunctional protein in our patient with Kindler syndrome resulted in severe gastrointestinal tract involvement with hemorrhagic colitis. Mucosa of the descending and sigmoid colon and the rectum showed erosions and ulcers with pseudomembranous alterations of an overall highly vulnerable mucosa. Mutation analysis revealed a homozygous status for the novel mutation 20/21delTT in exon 2 of the KIND1 gene resulting in a preterminal stop codon creating a nonfunctional peptide 17 amino acids in length. CONCLUSION: Because of our experience with this and another patient, we propose that gastrointestinal tract involvement should be looked at more frequently in Kindler syndrome.

Adult↗
PubMed1998

Localization of the beta(beta)3-adrenoceptor in the human gastrointestinal tract: an immunohistochemical study.

BACKGROUND: Activation of human and non-human colonic beta(beta)3-adrenoceptors causes smooth muscle relaxation. beta3-Adrenoceptor agonists protect against experimental indomethacin-induced jejunal ulceration. The mechanism of protection may involve spasmolytic/vasodilatory agonist activity. The precise localization of beta3-adrenoceptors in the human gut is not known. AIM: To localize the beta3-adrenoceptor within the human gastrointestinal tract using the immunohistochemical technique. METHODS: Human beta3-adrenoceptors were immuno-localized in paraffin sections of human oesophagus (OS), stomach (ST), duodenum (DU), ileum (IL), sigmoid colon (SC), rectum (R) and gall-bladder (GB) using the rabbit polyclonal antibody anti-P12. Staining was graded , ++, + and 0. Immunostaining of SC was also done with pre-incubation of anti-P12 with P12 peptide. Western blotting of anti-P12 on human and murine IL and SC isolated membrane proteins was performed. RESULTS: All epithelia, vascular endothelial cells and ganglia scored 0. Smooth muscle of the vasculature, muscularis propria, muscularis mucosae and mucosa was graded, respectively, as follows; OS ( , , ,-), ST (++, , ++, ++), DU (++, , , +), IL (++, ++, ++, +), SC ( , ++, ++, ++), R (++, ++, +, +), GB ( , , -, 0). Pre-incubation of anti-P12 with P12 peptide almost abolished SC smooth muscle positivity. Western blot analysis using anti-P12 on human, but not murine, IL and SC membrane proteins revealed a single 5 5 kDa band, a size consistent with the predicted size of a partially glycosylated form of the human beta3-adrenoceptor. CONCLUSIONS: This immunohistochemical study has localized the beta3-adrenoceptor to vascular and nonvascular smooth muscle in the human gastrointestinal tract. These findings support a role for the beta3-adrenoceptor in the control of blood flow and motility in the human gastrointestinal tract.

Amino Acid Sequence↗
PubMed2006

Phase III study of pentosanpolysulfate (PPS) in treatment of gastrointestinal tract sequelae of radiotherapy.

OBJECTIVES: To evaluate the effectiveness of pentosanpolysulfate (PPS) in the treatment of gastrointestinal tract sequelae of radiotherapy. METHODS: Eligible patients were those with grade 1 to 3 radiation related proctitis, diarrhea and/or melena. At least 4 weeks had to elapse since the completion of the radiotherapy course. Patients with bleeding diathesis or ulcers, and patients receiving anticoagulants or chemotherapy were excluded. Stratification criteria included the type of sequelae (proctitis, diarrhea, melena), the severity grade and the onset (<3 months post-RT, >3 months post-RT). Patients were randomized to one of the following arms: 100 mg PPS 3 times per day (300 mg/day), 200 mg PPS 3 times per day (600 mg/day), or placebo 3 times per day. If there was no improvement in symptoms after 2 months, the protocol treatment was discontinued. If the symptoms improved or resolved, the protocol treatment was continued for additional 4 months. Patients under treatment were evaluated monthly, than every 2 to 3 months for the next 18 months. A symptom assessment questionnaire was used to measure quality of life endpoints. RESULTS: From June 1999 to March 2001 180 patients were accessioned from 34 institutions. A total of 168 were analyzable. Neither the best observed response within 3 months for the entire population, nor the response rate within sequelae category or the quality of life measures differed significantly between the 3 arms of the study. CONCLUSION: Administration of PPS has not been associated with an improvement in the clinical course of radiation related morbidity of the gastrointestinal tract.

Administration, Oral↗
PubMed1999

Pharmacological effects of epidermal growth factor (EGF) with focus on the urinary and gastrointestinal tracts.

Epidermal growth factor (EGF) belongs to a family of growth factor ligands and receptors. At present, five ligands have been recognized which as EGF exert their effects via binding to the same EGF receptor. The family has three other receptors erbB2, erbB3, and erbB4, which have their own ligands (the heregulins). The system is ubiquitously distributed in mammals, and has important roles in normal development, and in regenerative and neoplastic growth. Mouse and human EGF were discovered in 1962 and 1975 by Stanley Cohen and Harry Gregory, respectively, due to EGFs potent systemic effects. EGF accelerated eyelid opening in newborn mice and inhibited gastric acid secretion in humans. Already in the late thirties, a factor in human urine was recognized which prevented or accelerated healing of experimental damage in the gastrointestinal tract. This factor appeared to be EGF. Around 1980, an effect of commercial interest was described-EGF caused shedding of the fleece in sheep. In line with the original observations, several studies have examined effects of EGF on developmental processes. Amongst other effects, EGF accelerates lung and intestinal maturation before birth and in newborn mammals. Due to the possible use of EGF in the wool industry, it was mandatory to know more about EGF. Amongst other effects in mature sheep and other animals are haemodynamic changes, changes in electrolyte homeostasis, and endocrinological changes. In relation to experimental damage, the therapeutic potential of systemic EGF has been demonstrated in all parts of the gastrointestinal tract, in the kidneys, in the liver and in the trachea. EGF has even been tried in humans in gastric ulcer healing and in necrotising enterocolitis. Studies on prolonged treatment with EGF have first recently appeared. We described effects of 4-5 weeks of treatment in Goettingen minipigs and in rats, and two other groups described effects in monkeys and in rats. In summary, species differences were observed. The species of higher order were most sensitive to treatment with EGF. EGF did not consistently change the total body weight despite EGF consistently reduced circulating levels of insulin-like growth factor I (IGF-I) in Goettingen minipigs as well as in rats. Low circulating levels of IGF-I are usually associated with retarded growth. This review mostly focuses on the organs which appeared to be most sensitive to EGF, the urinary and gastrointestinal tracts including the liver and the pancreas. The histopathological changes consisted mainly of epithelial proliferations in the gastrointestinal, urinary and respiratory tracts. These findings match the knowledge obtained from animals overexpressing the EGF agonist, transforming growth factor alpha (TGF alpha), and the mice with a knock out of the gene encoding for the EGF receptor. EGF receptor hyperstimulation (TGF alpha overexpression) in the context of the whole animal leads to epithelial proliferations whereas hypostimulation (EGF receptor knock out) leads to epithelial immaturities. In the minipigs, the epithelia of the oesophagus, ducts of the pancreas, and the urothelium were hyperplastic, the latter two epithelia with accumulation of glycoconjugates. In the rats, the epithelial hyperplasias in these tissues and in the small and large intestines were without glycoconjugate accumulations. In rats, the mucosal proliferations in the intestines resulted in increased mucosal surface area. Mesenchymal growth effects were also noted. In the ureters of the minipigs, smooth muscle cell hyperplasia and hypertrophia were found. The heart of the minipigs was also enlarged, an interesting finding regarding interactions between the different parts of the EGF system, as knock out mice of the receptors erbB2 and erbB4 die due to maldevelopments in the heart. Measurements in blood and serum also revealed consistent changes. (ABSTRACT TRUNCATED)

Animals↗
PubMed1987

Distribution of peptide-containing neurons and endocrine cells in the rabbit gastrointestinal tract, with particular reference to the mucosa.

The distribution patterns of peptide-containing neurons and endocrine cells were mapped in sections of oesophagus, stomach, small intestine and large intestine of the rabbit, by use of standard immunohistochemical techniques. Whole mounts of separated layers of ileum were similarly examined. Antibodies raised against vasoactive intestinal peptide (VIP), substance P (SP), somatostatin (SOM), neuropeptide Y (NPY), enkephalins (ENK) and gastrin-releasing peptide (GRP) were used, and for each of these antisera distinct populations of immunoreactive (IR) nerve fibres were observed. Endocrine cells were labelled by the SP, SOM or NPY antisera in some regions. VIP-IR nerve fibres were common in each layer throughout the gastrointestinal tract. With the exception of the oesophagus, GRP-IR nerve fibres also occurred in each layer of the gastrointestinal tract; they formed a particularly rich network in the mucosa of the stomach and small intestine. Fewer nerve fibres containing NPY-IR or SOM-IR were seen in all areas. SOM-IR nerve fibres were very scarce in the circular and longitudinal muscle layers of each area and were absent from the gastric mucosa. The SP-IR innervation of the external musculature and ganglionated plexuses in most regions was rather extensive, whereas the mucosa was only very sparsely innervated. ENK-IR nerve fibres were extremely rare or absent from the mucosa of all areas, although immunoreactive nerve fibres were found in other layers. These studies illustrate the differences in distribution patterns of peptide-containing nerve fibres and endocrine cells along the gastrointestinal tract of the rabbit and also show that there are some marked differences in these patterns, in comparison with other mammalian species.

Animals↗
PubMed2006

Progastrin-releasing peptide and gastrin-releasing peptide receptor mRNA expression in non-tumor tissues of the human gastrointestinal tract.

AIM: To investigate the expression of gastrin-releasing peptide (GRP) and GRP-receptor mRNA in non-tumor tissues of the human esophagus, gastrointestinal tract, pancreas and gallbladder using molecular biology techniques. METHODS: Poly A(+) mRNA was isolated from total RNA extracts using an automated nucleic acid extractor and, subsequently, converted into single-stranded cDNA (ss-cDNA). PCR amplifications were carried out using gene-specific GRP and GRP-receptor primers. The specificity of the PCR amplicons was further confirmed by Southern blot analyses using gene-specific GRP and GRP-receptor hybridization probes. RESULTS: Expression of GRP and GRP-receptor mRNA was detected at various levels in nearly all segments of the non-tumor specimens analysed, except the gallbladder. In most of the biopsy specimens, co-expression of both GRP and GRP-receptor mRNA appeared to take place. However, expression of GRP mRNA was more prominent than was GRP-receptor mRNA. CONCLUSION: GRP and GRP-receptor mRNAs are expressed throughout the gastrointestinal tract and provides information for the future mapping and determination of its physiological importance in normal and tumor cells.

Adult↗
PubMed1986

One hundred and fourteen fistulas of the gastrointestinal tract treated with total parenteral nutrition.

During a period of five years, all patients with fistulas of the gastrointestinal tract who received total parenteral nutrition as a part of the therapy were evaluated retrospectively. One hundred and eight patients with 114 fistulas of the gastrointestinal tract were studied. There were 58 male and 50 female patients. The mean age of the patients was 58 years old. Fifty-one per cent (58) of all fistulas resulted from surgical complications and 30 per cent from inflammatory disease. The most common origin of the fistula was the small intestine (48 per cent), with the large intestine being the next most common origin (26 per cent). Ninety-eight of the fistulas were treated successfully. The mean time for closure from the time of diagnosis was 30.9 days. Sixty-one per cent (69) of all fistulas closed spontaneously, the use of parenteral nutrition resolved 37 per cent (42) and 24 per cent (27) resolved after surgical control of sepsis. Twenty-five per cent (29) of the fistulas required definitive surgical closure. Sixteen patients died prior to resolution of the fistula, 11 deaths were directly related to septic complications of the fistula and one died as a result of hemorrhage of the fistula tract. The direct fistula-related mortality rate was 10.5 per cent. Whereas the mortality rate for fistulas remained stable, spontaneous closure rates continue to improve. This is attributed to improved "para-surgical" care, appropriate nutritional support and early and aggressive control of sepsis. Ninety to 95 per cent of fistulas that spontaneously resolve will do so within four to five weeks. Inflammatory disease of the intestine and radiation induced fistulas continue to respond poorly to medical management.

Adult↗
PubMed1994

Distribution and developmental pattern of neuromedin U expression in the rat gastrointestinal tract.

This study has quantified, for the first time, the relative levels of neuromedin U (NmU) mRNA in the rat gastrointestinal tract using Northern blot analysis. NmU message was detected in all regions of the gastrointestinal tract from the oesophagus to the rectum. The greatest levels were found in the duodenum and jejunum, the principal sites for absorption, which were 2.5- and 3-fold respectively above ileal levels. Quantification of NmU mRNA and peptide contents in the duodenum, jejunum and ileum during postnatal development of the rat showed message and peptide levels to be greater in the maturing rat than in neonates. Message levels in the duodenum, jejunum and ileum showed 14-, 7- and 4-fold increases respectively between 1 and 56 days after birth, whilst the corresponding peptide levels in the duodenum, jejunum and ileum showed 33-, 14- and 25-fold increases respectively. Food deprivation caused a small, but significant, decrease in message levels in the jejunum and colon, but there was no change in the duodenum or ileum. This shows that the presence of food has little effect on NmU mRNA levels in the gut.

Age Factors↗
PubMed1993

Escherichia coli K12 does not colonize the gastrointestinal tract of Fischer-344 rats.

The colonizing potential of Escherichia coli K12 containing a vector coding for somidobove (bovine somatotropin) was determined. Treated male and female Fischer-344 rats were given a single oral gavage inoculum of sucrose with/without tetracycline (15 micrograms/ml). Untreated control animals received similar drinking water regimes. All animals survived until termination. There were no clinical signs of toxicity observed and no treatment-related effect upon body weight, food consumption, or efficiency of food utilization. Fresh fecal samples were collected from each rat every 24 h following inoculation and the population of the marked strain was quantitated until no bacterial colonies were observed for two consecutive days. While all inoculated rats were positive at 24 h, by 72 and 96 h all had become negative for the test (marked) strain, as were the corresponding control group throughout the test. The frozen stock of the marked strain used as the positive control demonstrated that the agar plates were selective for the test strain. Fourteen days following inoculation, all groups of rats were killed and the gastrointestinal tracts removed and treated to recover the marked strain. There was no evidence of the marked strain in the gastrointestinal tract of any from any group. Thus, the E. coli K12 host/vector system used in this experiment does not colonize the gastrointestinal tract of Fischer-344 rats.

Animals↗
PubMed1997

[Functional properties of dietary fiber. Mechanisms of action in the gastrointestinal tract].

Physiological effects of dietary fiber (DF) are the result of complex interacting mechanisms between the components of food which is not digested by the endogenous enzymes of the digestive tract and the conditions of gastrointestinal environment, such as pH, ionic strength and other food components. Chemical nature and structure of each component of DF are two factor that determine their behaviour in lumen intestinal. This article report the main functional properties of DF and explain how these are responsible of physiological effects developed by DF in gastrointestinal tract.

Dietary Fiber↗
PubMed2000

Pharmacokinetics and penetration of danofloxacin into the gastrointestinal tract in healthy and in Salmonella typhimurium infected pigs.

The pharmacokinetics and penetration of danofloxacin into the gastrointestinal tract in healthy pigs and in pigs experimentally infected with Salmonella typhimurium were studied. In the infected pigs, a decrease in body clearance and an increase in mean elimination half-life was observed (P < 0.01). Moreover a significant reduction in the volume of the peripheral compartment was found. Danofloxacin distributed well to the gastrointestinal tract achieving high AUC / AUC(plasma)ratios in both groups of pigs. However, compared to the healthy pigs AUC / AUC(plasma)ratios decreased in the infected pigs. Salmonella infection led to an increase in mean residence time (MRT) in the small intestines and lymph nodes and a decrease in MRT in caecum and colon.

Animals↗
PubMed2001

Presence of melatonin in the human hepatobiliary-gastrointestinal tract.

A variety of speculations about the possible origin and physiological role of the neurohormone melatonin in the gastrointestinal tract exist. However, the experimental evidence supporting any of these theories is not substantial and are missing for humans. We studied the distribution of melatonin which was measured with radioimmunoassay in the following compartments and organs of the human hepatobiliary-gastrointestinal tract: bile (obtained by endoscopic retrograde cholangiopancreaticography), peripheral venous and portal venous blood (obtained from patients undergoing liver transplantation), endoscopically derived biopsies (mainly consisting of mucosa and submucosa) of stomach, duodenum, large intestine as well as in resected liver tissue. Melatonin concentrations in gastrointestinal mucosa were between 136 +/- 27 pg/100 mg (stomach) and 243 +/- 37 pg/100 mg (descending colon, each n = 5). Biliary melatonin concentrations (85 +/- 45 pg/ml) correlated well with plasma concentrations (55 +/- 38 pg/ml, each n = 14) and a considerable amount of melatonin (about 51 ng/24 hours) appears to be excreted into the gut via the bile duct. Melatonin concentrations were slightly higher in portal than in peripheral venous blood and also the liver contained higher concentrations of melatonin than the blood. In conclusion the presence and distribution of melatonin in human gut, bile, liver and portal blood and the various reports on modulatory actions of melatonin on gut and liver functions suggest that melatonin may act as a mediator of inter-organ communication between gut and liver.

Adolescent↗