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: This study aimed to investigate the consequences ofHelicobacter pylorieradication and acid suppression on rehaemorrhage caused by bleeding peptic ulcers.: A total of 320 patients who had been diagnosed with bleeding peptic ulcers between January 1994 and December 2001 were included in the study. Cases between 1994 and 1997, prior to the introduction of eradication therapy, were assigned to group A, whereas those between 1998 and 2001, after the eradication therapy, were assigned to group B.: Of the 320 cases, 162 were designated as group A (113 gastric ulcers and 49 duodenal ulcers) and 158 as group B (116 and 42, respectively). Rehaemorrhage occurred in 24 cases (15%) and five cases (3%) in groups A and B, respectively, presenting a significantly decreased rate of rehaemorrhage in group B. Among those without eradication, rehaemorrhage was observed in 15 of 128 cases (12%) that received treatment with histamine2-receptor antagonist (famotidine), and 14 of 142 cases (10%) treated with proton-pump inhibitors, with no significant difference between the two.: Helicobacter pylorieradication lowered the rates of rehaemorrhage. Treatment with histamine2-receptor antagonist or proton-pump inhibitors did not produce a difference in the rate of rehaemorrhage. [ABSTRACT FROM AUTHOR]

Dietary factors such as taste and nutrients are known to affect satiety and energy balance. We hypothesized that food texture might contribute to the regulation of energy metabolism through the process of mastication in the oral cavity as well. The effects of long-term feeding of different-textured pellets on body weight gain, adiposity, and thermogenesis were assessed. From weaning at 4 wks, rats were divided into 2 groups fed on either standard (controls) or soft pellets (soft-fed) that required less chewing with the same nutritional composition. At 26 wks, the soft-fed rats showed greater adiposity than did the controls. Daily food intake did not differ between the 2 groups. The increase in body temperature following feeding was significantly lower in the soft-fed rats. These results suggested that food texture affected energy metabolism by changing post-prandial thermogenesis. The long-term deficiency of thermogenesis associated with soft foods resulted in a greater tendency toward obesity. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study is to investigate the characteristics of bleeding peptic ulcer in Japan, including the role of H. pylori infection and NSAIDs use. Patients and Methods: This study was prospectively intended for patients who have a bleeding peptic ulcer at emergent endoscopy in our hospital in 1998 to 2001. We grouped these patients by H. pylori infection and NSAIDs use, and examined backgrounds of patients; i.e., age, sex, underlying disease, location of ulcer. Results: We devided 128 patients with bleeding gastric or duodenal ulcer into 4 groups. Group A (71, 55.5%); H. pylori (+), NSAIDs (-). Group B (10, 7.8%); H. pylori (+), NSAIDs (+). Group C (14, 10.9%); H. pylori (-), NSAIDs (+). Group D (33, 25.8%); H. pylori (-), NSAIDs (-). Age in patients with use of NSAIDs was high (Group B and C). In Group C, females were more than males. Corporeal ulcer of group D was higher than that of group A. Duodenal ulcer of group A was higher than that in other groups. Most of patients with Group B, C, had underlying disease compared to patients with H. pylori related ulcer (Group A). But, the underlying disease of Group D was more severe than that of Group B and C. Contents of underlying diseases were liver cirrhosis, congestive heart failure, and coronary disease. Rebleeding cases were 5 of all, and each case were gastric ulcer. Death cases were 5 of all the patients, and the causes of the death were due to severe underlying diseases. Conclusions: In Japan, The patients who have bleeding peptic ulcer without H. pylori infection and NSAIDs use were relatively high compared to that with H. pylori infection. And one of the characteristics in these patients was to have severe underlying disease. [ABSTRACT FROM AUTHOR]

Elevated lactate levels are associated with a poor prognosis in patients with sepsis and shock. Intravenous glycerol administration is often used in Japan to treat patients with acute stroke or brain trauma, but such treatment can cause elevated lactate levels. We experienced a case of transient hyperlactatemia induced by intravenous glycerol administration in a patient with brain trauma. A 74-year-old woman underwent decompressive craniotomy because of loss of consciousness and brain edema. Glycerol was administered after the operation for management of the brain edema. Although the patient's hemodynamics remained stable, her lactate level decreased and increased repeatedly. We recognized that the elevation in her lactate level was associated with the administration of intravenous glycerol. This case suggests that intravenous glycerol administration can induce transient hyperlactatemia.

Background and study aims  The aim of the present study was to determine whether blue-laser imaging (BLI) reduced the miss rate of colon adenomatous lesions compared with conventional white-light imaging (WLI). Patients and methods  This was a prospective randomized study of patients undergoing screening and/or surveillance colonoscopy at Saga Medical School, Japan. A total of 127 patients were randomized to tandem colonoscopy with BLI followed by WLI (BLI-WLI group) or WLI followed by WLI (WLI-WLI group). The main outcome measure was the adenoma miss rate. Results  The proportion of patients with adenomatous lesions was 62.5 % (40 /64) in the BLI-WLI group and 63.5 % (40 /63) in the WLI-WLI group. The total number of adenomatous lesions detected in the first inspection of the BLI-WLI and WLI-WLI groups was 179 and 108, respectively, compared with 182 and 120 in the second inspection, respectively. The miss rate in the BLI-WLI group was (1.6 %), which was significantly less than that in the WLI-WLI group (10.0 %, P  = 0.001). Conclusions  Colonoscopy using BLI resulted in a lower colon adenoma miss rate than WLI.Trial registration UMIN 000015677., (© Georg Thieme Verlag KG Stuttgart · New York.)

Aim: The aim of this study was to evaluate risk factors for proton pump inhibitor (PPI) resistance in older Japanese female patients with reflux esophagitis evaluated by physicians., Methods: The study included 462 Japanese female patients aged over 60 years with reflux esophagitis who received PPI maintenance therapy for more than 6 months., Results: The characteristics of all 462 patients were: age: 76.4 ± 7.6 years, height: 147.2 ± 6.1 cm, weight: 49.9 ± 8.4 kg and body mass index: 24.0 ± 3.5. The reflux esophagitis grades were A in 69.5%, B in 15.8%, C in 9.1% and D in 5.6%. Helicobacter pylori was positive in 60.6%. Regarding PPI maintenance therapy for clinical symptoms evaluated by the attending physicians, 66.7% were 'good control', 26.8% were 'reasonable control' and 6.5% were 'bad control: resistant'. PPI maintenance therapy was less effective in patients with more severe reflux esophagitis of grades C and D (OR: 0.027; 95% CI: 0.010-0.077) and negative H. pylori infection status (OR: 4.470; 95% CI: 1.631-12.247). Lumbar kyphosis and hiatus hernia were risk factors for severity grading of reflux esophagitis., Conclusions: PPI maintenance therapy evaluated by attending physicians indicated that reflux esophagitis severity and negative H. pylori status were risk factors for treatment resistance., (Copyright © 2012 S. Karger AG, Basel.)

Background: This retrospective study aimed to determine risk factors associated with serious complications of endoscopic submucosal dissection of gastric tumors in multicenters compared between high- and low-volume centers., Methods: Between 2001 and 2010, gastric endoscopic submucosal dissection was performed in 1190 lesions of 1082 patients in five hospitals in Saga, three high-volume and two low-volume centers. Risk factors for serious complications were evaluated. Patients' background characteristics were evaluated, including anticoagulants use and underlying diseases., Results: Postoperative bleeding was detected in 75 patients (6.9%), and perforation was detected in 40 patients (3.7%). Most postoperative bleeding and perforation cases were recovered with endoscopic procedures, although one case of each complication was treated by emergency surgery. Multivariate analysis indicated that risk factors for perforation were tumor location, massive submucusal invasion, endoscopists' experience of 100-149 cases and hypertension, and that risk factors for postoperative bleeding were tumor location, resected tumor size, and scar lesion. The serious complications were not different between high- and low-volume centers., Conclusions: The present study indicated that risk factors for perforation during endoscopic submucosal dissection were tumor, endoscopist and patient related, although risk factors for postoperative bleeding were tumor related. There was no difference in complications between high- and low-volume centers., (Copyright © 2012 S. Karger AG, Basel.)

Background/aims: We have previously shown that long-term consumption of 10% beef tallow diet promotes colon carcinogenesis in both saline- and azoxymethane (AOM)-treated rats. Here, we investigated the effects of mofezolac, a selective COX-1 inhibitor, on beef tallow-fed rats with saline- or AOM treatment., Methodology: Male SD rats were intraperitoneally injected with saline or AOM and fed 10% beef tallow diet with or without 1200 ppm mofezolac. At 12 weeks, aberrant crypt foci (ACF) were examined. At 44 weeks, tumors were counted, the proliferation and expression of COX-1 and 8-catenin on normal-appearing colonic mucosa was evaluated using the BrdU incorporation assay and Western blotting respectively., Results: Mofezolac decreased the number of ACF at 12 weeks (p < 0.05) and reduced tumor multiplicity and incidence at 44 weeks in beef tallow-fed rats with AOM treatment (p < 0.05). At 44 weeks, reduction of the BrdU-positive cells (p < 0.05) and beneficial distribution changes of these cells within the colon crypts in both groups with mofezolac supplementation were observed. The expression of COX-1 and beta-catenin also reduced in mofezolac-added groups simultaneously (p < 0.05)., Conclusions: This study suggested that mofezolac suppressed beef tallow-promoted colon carcinogenesis in rats, which probably was, appropriate for populations with high fat intake.

Background: We have indicated previously that long-term feeding of beef tallow increases colorectal cancer in rats. In this study, we investigated the effects of conjugated linoleic acid (CLA) on colon carcinogenesis in rats under long-term feeding of beef tallow diets, pretreated with azoxymethane (AOM)., Methods: Six-week-old male Sprague-Dawley rats were fed with 10% beef tallow diet only, 10% beef tallow with 1% CLA in triglyceride form (CLA-TG), or 10% beef tallow with 1% CLA in free fatty acid form (CLA-FFA). Colon carcinogenesis was induced by two intraperitoneal injections of AOM. Aberrant crypt foci (ACFs) were examined at 12 weeks. Cancer, cell proliferation, apoptosis, Wnt signaling, and the arachidonic acid cascade were examined at 44 weeks., Results: At 12 weeks, CLA-TG and CLA-FFA attenuated the increase in ACFs induced by 10% beef tallow and AOM pretreatment. At 44 weeks, both forms of CLA attenuated multiple colon cancers, and CLA-FFA reduced the incidence of colon cancer to 50% of that seen with CLA-TG. CLA-TG and CLA-FFA decreased the number of 5-bromo-2'-deoxyuridine-positive cells in AOM-pretreated rats fed with 10% beef tallow. CLA-FFA increased the number of apoptotic cells and the activity of caspase-3 in the colon mucosa, and CLA-TG enhanced the activity of caspase-3. Both forms of CLA suppressed Wnt signaling and the arachidonic acid cascade in rats treated with beef tallow and AOM., Conclusion: These results suggested that CLA-TG and CLA-FFA suppressed colon carcinogenesis in rats with long-term feeding of a 10% beef tallow diet, through several mechanisms. The results of the present study with rats might be applicable to humans.

Purpose: Endoscopic submucosal dissection (ESD) technique has facilitated en bloc removal of widely spread lesions from the stomach. This retrospective study aimed to determine factors associated with serious complications of ESD., Methods: Between December 2001 and March 2007, we have performed ESD for 478 lesions in 436 patients. We experienced 39 patients with post-operative bleeding and 17 patients with perforation. Risk factors of patients who received ESD in gastric mucosal tumors for complications were evaluated, focusing on resected size, location, scar lesions, operation time, and experience of endoscopists. We evaluated the patients' background characteristics including sex, age, body mass index (kg/m(2)), drug history of anticoagulant, and underlying diseases including cerebrovascular disorder, ischemic heart disease, liver dysfunction, renal dysfunction, hyperuricemia, hypertension and diabetes mellitus., Results: Multivariate analysis indicated a risk factor for perforation was long operation time. Multivariate analysis indicated a significant risk factor for post-operative bleeding was size of the resected tumor., Conclusions: This study indicated risk factors for serious complications of ESD. Large resected tumor size was a risk factor for post-operative bleeding, while long operation time was a risk factor for perforation. Information regarding operation risk factors should be useful for planning strategies for ESD.

Purpose: We have shown previously that long-term feeding of beef tallow increases colorectal cancer in rats. This study investigated the effects of enzymic antioxidant, reduced glutathione (GSH), on colon carcinogenesis in rats fed with beef tallow., Methods: Colon carcinogenesis was induced by intraperitoneal injection of azoxymethane (AOM) to rats. Rats were fed with 10% beef tallow supplemented with or without 1% GSH in drinking water. Aberrant crypt foci (ACF) and expression of beta-catenin in colonic mucosa were examined at 12 weeks. Cancers, related substances of oxidative stress and arachidonic acid cascade in plasma and normal colonic mucosa were determined at 44 weeks., Results: GSH attenuated the number of ACF increased by beef tallow, but GSH had no influence on expression of beta-catenin increased by AOM. Incidence of colon cancer was no different with or without GSH, but GSH attenuated the number of colon cancers in each rat. GSH suppressed plasma malondialdehyde concentration. GSH increased GSH concentration and activities of catalase, glutathione peroxidase and superoxide dismutase in colonic mucosa, and decreased cyclooxygenase-2, prostaglandin E2 and thromboxane B2 levels., Conclusions: This study indicated that GSH suppressed the number of ACF, but the attenuation of colon carcinogenesis was limited to the number of colon cancers, although anti-oxidative effects and suppressive effects of arachidonic acid cascade were demonstrated by several indexes. These results suggested that colon carcinogenesis enhanced by beef tallow was partly caused by oxidative stress and arachidonic acid cascade, which were reduced by GSH.

Aim: Applied endoscopic techniques including mucosal resection, sclerotherapy and endoscopic retrograde cholangiopancreatography (ERCP) have been advanced and iatrogenic complications including Mallory-Weiss tear (MWT) occasionally occur in daily endoscopic procedures. The present study aimed to examine the advantages of clipping for MWT complications that occur during endoscopic examination., Methods: Over 10 years, we experienced 47 patients with bleeding caused by MWT. Metallic hemoclips were applied for 38 patients for hemostasis. These patients were categorized into two groups: 18 patients in group A whose bleeding tear occurred during endoscopic examination in an iatrogenic condition, and 20 patients in group B visited the emergency unit due to other etiology of MWT., Results: The background characteristics, including length of tears, were not different between the two groups. Initial hemostasis was 100% in groups A and B. Rebleeding was 0/18 (0%) in group A and 1/20 (5 %) in group B. Number of patients who received blood transfusion was significantly higher in group B (group A: 0/18, group B: 4/20). Hemoglobin level before hemostasis was 12.5 g/dL in group A which was not different to that in group B, 10.9 g/dL., Conclusion: Application of hemoclips was effective for bleeding MWT during endoscopic procedures, which warranted prophylactic application of hemoclips on MWT during endoscopic examination.

Background: Endoscopic submucosal dissection (ESD) plays an important role in the management of gastric neoplasms. There are few reports regarding stricture development caused by ESD of gastric neoplasms., Objective: The present study aimed to determine the incidence of gastric stricture formation after ESD of gastric neoplasms and to report on the outcome and management of this complication: endoscopic intervention (ie, balloon dilation) versus surgery; the outcome of balloon dilation (success or failure/perforation)., Design: A case series from a retrospective review of gastric ESDs performed at Saga Medical School over a defined period of time., Setting: Double-center territory, referral hospital., Patients: An evaluation was performed in 532 patients with gastric mucosal tumors treated by ESD. A stricture was reported in 5 patients. All the 5 cases were located in the antrum. ESD that was performed in the cardia or the proximal stomach did not induce a stricture., Results: Of the 5 cases of symptomatic gastric outlet obstruction, 1 patient required surgical intervention because of a near total gastric outlet obstruction not amenable to endoscopic intervention. The 4 patients underwent step-serial through-the-scope balloon dilations; in 2 patients, the procedure was successful, but in the other 2 patients, the procedure was complicated by a gastric perforation (50% incidence of perforation)., Limitation: A retrospective study., Conclusions: Circumferential or subcircumferential resection by ESD in the antrum caused a stricture. Balloon dilation of the ESD gastric outlet obstruction might be a choice, but it is a risky treatment.

This case report showed a laterally spreading tumor treated by endoscopic mucosal resection that developed as an advanced colon cancer. A 74-year-old female was visited to treat a colon tumor that was pointed out at another hospital. Total colonoscopy revealed a laterally spreading tumor (LST) 25 mm in diameter in the cecum. The lesion was diagnosed as homogenous granular type LST (G-type LST) and treated by endoscopic piecemeal mucosal resection in January 2004. A tumor was recognized by follow-up endoscopic examination in April 2006. The scar of endoscopic piecemeal mucosal resection had developed to advanced colon cancer and was treated by laparoscopy-associated ileocecal resection with D3 lymph node resection. Previous reports indicated that G-type LST in the colon could be treated by piecemeal resection, but this report suggests that G-type LST resected by piecemeal endoscopic mucosal resection might develop to advanced colon cancer.

We have previously demonstrated that fasting induced apoptosis and decreased cell proliferation in the rat intestinal mucosa. The aim was to investigate the effect of expanded polystyrene as indigestible material on apoptosis and cell proliferation in rat small intestinal mucosa during fasting. Male SD rats were divided into 3 groups. The first group was fed with chow and water ad libitum. The second group fasted for 72 hrs. The third group was fasted for 24 hrs and was fed expanded polystyrene. Intestinal apoptosis was evaluated by percent fragmented DNA assay, terminal deoxynucleotidyl transferase-mediated dUDP-biotin nick end-labeling (TUNEL) staining, and caspase-3 assay. Cell proliferation was analyzed by 5-bromo-2'-deoxyuridine (5-BrdU) uptake. Truncal vagotomy was performed to evaluate a role of the central nervous system. In the 72-hr fasted rat, mucosal height of the rat jejunum was decreased to 73% of that in rats fed ad libitum, and this decrease was partly restored to 90% in rats fed expanded polystyrene. The fragmented DNA was increased in fasted rats (28.0%) when compared with that in rats fed ad libitum (2.6%). The increase in fragmented DNA in fasted rats was recovered by feeding them expanded polystyrene (8.3%). TUNEL staining confirmed this result. The effect of polystyrene on apoptosis was decreased by truncal vagotomy. Expression of cleaved caspase-3 was increased in fasted rats, which was then decreased by feeding of expanded polystyrene. In contrast to apoptosis, feeding of expanded polystyrene had no reconstructive effect on 5-BrdU uptake in the intestinal epithelium, which was decreased by fasting to 60% of that in rats fed ad libitum. In conclusion, feeding of indigestible material partly restored the decrease in intestinal mucosal length in the fasted rats through the apoptotic pathway without any influence on BrdU uptake. Further exploration focused on the mechanism of this effect of indigestible material is required.

Objective: This study aimed to evaluate the possible effects of Helicobacter pylori (H. pylori) infection in reflux esophagitis with scleroderma., Patients and Methods: There were a total of 138 patients with scleroderma in our hospital between October 1998 and June 2005. Among these patients, 64 consecutive patients of scleroderma, who did not receive medication for gastrointestinal diseases, underwent endoscopy after informed consent. H. pylori was examined using an H. pylori IgG ELISA. The endoscopists graded esophageal mucosal breaks according to the Los Angeles Classification of Esophagitis., Results: Among the 64 patients, 37 patients (57.8%) were positive for H. pylori infection. Reflux esophagitis was observed in 10 of 37 H. pylori-positive patients and in 19 of 27 H. pylori-negative patients. Significantly fewer H. pylori-infected patients had reflux esophagitis than H. pylori-negative patients (p<0.01). The odds ratio for H. pylori infection and reflux esophagitis was 0.16 (95%CI; 0.052-0.47)., Conclusion: These findings suggest an important role for H. pylori infection in reflux esophagitis with scleroderma.

Ghrelin is mainly produced in the stomach and has several physiologic functions. The aim of this study was to investigate whether ghrelin regulates apoptosis in the small intestinal mucosa of fasting rats. Intestinal mucosal apoptosis was evaluated as the percentage of fragmented DNA, villus height, and terminal deoxynucleotidyl transferase-mediated dUDP-biotin nick end-labeling (TUNEL) staining and by Western blot analysis of caspase-3 in 48-hr fasting rats. Crypt cell proliferation was evaluated by counting the number of 5-bromo-2-deoxyuridine (BrdU) positive cells. Ghrelin was administered intraperitoneally at dosages of 2.5, 25, and 250 microg/kg per 48 hrs by continuous infusion via an Alzet micro-osmotic pump or injections at 12-hr intervals. Ghrelin was also infused in rats that underwent truncal vagotomy. The lowest dosage of ghrelin (2.5 microg/kg per 48 hrs) was administered into the third cerebroventricle. Ghrelin treatment attenuated the percentage of fragmented DNA in the small intestinal mucosa in 48-hr fasting rats in a dose-dependent manner. Continuous infusion of ghrelin and injections of ghrelin at 12-hr intervals suppressed intestinal apoptosis almost equally. This effect on apoptosis was not attenuated by truncal vagotomy. Cerebroventricular infusion of ghrelin also attenuated intestinal apoptosis. The antiapoptotic effect of ghrelin was confirmed by decreased TUNEL staining, recovery of the villus height, and decreased expression of caspase-3. BrdU uptake indicated that ghrelin enhanced cell proliferation in the intestinal crypt. Taken together, these data indicate that ghrelin enhanced intestinal growth with the suppression of small intestinal mucosal apoptosis in 48-hr fasting rats, suggesting that ghrelin controls intestinal function through the regulation of intestinal apoptosis.

Background and Aim: The aim of the present study was to examine the role of mitogen-activated protein (MAP) kinase pathway on gastric surface epithelium using an established cell culture model in which differentiation is promoted in GSM06 cells by air-liquid interface., Methods: A double-dish culture system of mouse gastric surface mucous cell line GSM06 in Ham's F12 medium supplemented with 10% fetal calf serum and 50 microg/mL gentamicin at 37 degrees C in a humidified atmosphere of 5% CO(2) in air was used for an air-liquid interface. Culture cells were examined on histology, cell proliferation was evaluated by bromodeoxy-uridine (BrdU) uptake, and western blot analysis of extracellular signal-regulated kinase (ERK)1/2 and phosphate ERK1/2. On day 3, U0126, an inhibitor of MAP kinase kinase (MEK), was added to medium of incubated cells., Results: GSM06 cells were differentiated with an air-liquid interface for 3 weeks. Compared to immersion control culture, phosphorylated ERK 1/2 expression increased significantly. This increase was completely suppressed with U0126, and tall columnar cells developed by air-liquid interface in GSM06 were not observed in U0126-treated cells. Increase in BrdU uptake with air-liquid interface was suppressed by U0126., Conclusion: These results suggested that MAP kinase signaling, activated by air-liquid interface, was, at least in part, related to cell differentiation in GSM06 cells induced by air-liquid interface.

The Wnt signaling pathway plays an essential role in carcinogenesis, and the amount of fat intake and composition of dietary fatty acids are crucial factors for colon carcinogenesis. We investigated whether various dietary fats affected the Wnt signaling pathway of colon tumorigenesis in azoxymethane (AOM)-treated rats. Male Sprague-Dawley rats were given intraperitoneal injections of AOM and supplemented with 10% corn, olive, beef, and fish oil for 44 wk. Aberrant crypt foci (ACF) and tumors were examined at 12 and 44 wk. Normal appearing colon mucosal proliferation and apoptosis were evaluated by 5-bromo-2'-deoxyuridine (BrdU) incorporation and percentages of fragmented DNA, respectively. Expressions of beta-catenin, cyclin D(1), Wnt2, Wnt3, and Wnt5a of normal appearing colon mucosa were analyzed by Western blot analysis. Long-term dietary corn oil and beef tallow increased ACF, tumor incidence, and tumor numbers in AOM-treated rats. In contrast, both olive and fish oil inhibited them. Dietary corn oil and beef tallow increased BrdU incorporation and the expression of cytosolic beta-catenin and cyclin D(1) and decreased apoptosis in the colon mucosa. Expressions of Wnt2 and Wnt3 in rats fed with beef tallow and Wnt5a in rats fed with corn oil increased with or without AOM-treatment. BrdU-incorporated cells were often observed at the tops of crypts in rats fed with beef tallow, whereas this was not observed in rats fed with the other diet. Long-term high intake of corn oil and beef tallow enhanced cell proliferation through Wnt signaling and modulated the distribution of proliferating cells, which might contribute to promoting effects in colon tumorigenesis.

Obesity, a risk factor for colon cancer, is associated with elevated serum levels of leptin, a protein produced by adipocytes. The aim of the present study was to clarify the effects of adipose tissue on colon cancer proliferation by using cultured cell lines. To achieve this, colon cancer cells (CACO-2, T84, and HT29) were cocultured with adipose tissue, isolated mature adipocytes, and isolated preadipocytes in a three-dimensional collagen gel culture system. The adipocytes and preadipocytes used were isolated from C57BL/6J and leptin-deficient ob/ob mice. Proliferation of the cancer cells was evaluated by nuclear bromodeoxyuridine uptake. The adipose tissue, mature adipocytes, and preadipocytes isolated from C57BL/6J mice significantly increased the proliferation of the colon cancer cells. This trophic effect of mature adipocytes on the cancer cell lines was observed only for cells from lean littermates and not for those from ob/ob mice. In contrast, the trophic effect of preadipocytes was not abolished in ob/ob mice, and this finding was supported by the result that leptin had a trophic effect on cancer cells. In conclusion, adipocytes were able to enhance the proliferation of colon cancer cells in vitro, partly via leptin, suggesting that adipose tissues, including mature adipocytes and preadipocytes, may promote the growth of colorectal cancer.

Objective: This study was aimed to evaluate the correlation between dysphagia, detected by nursing staff in a brief interview and endoscopic findings in reflux esophagitis., Patients and Methods: A total of 8,031 Japanese subjects without medication for gastrointestinal disease were briefly asked about the presence of heartburn, dysphagia, odynophagia, and acid regurgitation by nursing staff before endoscopy for assessment of esophagitis utilizing the Los Angeles Classification., Results: The grade of endoscopic esophagitis was not equivalent to symptoms of dysphagia in 8,031 subjects. We evaluated the characteristics of subjects who complained of only dysphagia. Univariate analysis indicated that non-smoking, and non-drinking females were associated with a higher risk for dysphagia, and multivariate analysis indicated the gender was associated with dysphagia. There was no association of dysphagia with herniation and distribution of age., Conclusion: This study indicated that dysphagia was not equivalent to the endoscopic findings according to a brief interview by nursing staff and that dysphagia might be more common in females and those who do not smoke or drink.

We have previously demonstrated that fasting and ischemia-reperfusion (I/R) induced apoptosis in rat intestinal mucosa. It is widely accepted that apoptosis is induced through two main pathways. This study aimed to compare apoptotic pathways following fasting and I/R. Rats were divided into two groups: the I/R group involved occlusion of the superior mesenteric artery for 60 min, followed by 60-min reperfusion, whereas the fasting group involved fasting for 24 or 48 h. Intestinal apoptosis was assessed as percentage of fragmented DNA, by electrophoresis and by a terminal deoxynucleotidyl transferase mediated dUDP-biotin nick- end labeling (TUNEL) assay. Apoptotic proteins including death ligands/receptors and caspases were evaluated by Western blot analysis. Small intestinal mucosal height and mitochondrial dehydrogenase function were assessed. Fasting and I/R significantly induced intestinal apoptosis. Mucosal height was significantly decreased in fasting rats, and mitochondrial dysfunction was induced only by I/R. Expressions of Fas, Fas ligand, and TNF-alpha type 1 receptor were enhanced in fasting and I/R rats. After I/R, expressions of cytochrome c and cleaved caspase-9 were significantly increased. In contrast, expressions of cleaved caspase-8 and cleaved caspase-3 increased in fasting rats. Fasting promoted mucosal apoptosis via a receptor-mediated type I apoptotic pathway in the rat small intestine, and I/R induced apoptosis via a mitochondria-mediated type II pathway.

Background: Helicobacter pylori infection and nonsteroidal anti-inflammatory drugs (NSAIDs) are well-known major causes of peptic ulcers. This study aimed to characterize the features of bleeding peptic ulcers in Japan., Methods: This prospective study evaluated 116 patients revealed to have bleeding peptic ulcers from January 2000 to December 2002., Results: Eighty-eight of the 116 patients (75.9%) had H. pylori infection. Seventy (60.3%) patients were positive for H. pylori with no history of NSAID use (group A), and 18 (15.5%) were positive for H. pylori with a history of NSAID use (group B). Among the H. pylori-negative patients, 15 (12.9%) were associated with NSAID use (group C). Thirteen (11.2%) patients had no H. pylori infection or history of NSAID use (group D). Among the 33 patients with a history of NSAID use, 11 were on-demand NSAID users and 14 took daily low-dose aspirin. The patients in groups B and C were significantly older that those in groups A and D, and they more frequently had coexisting diseases compared with group A. In group D, 11 patients had atrophic changes revealed by endoscopic examination, suggesting a past H. pylori infection, and these atrophic changes remained at the time of bleeding. Many of the patients in group D had serious comorbidity. Compared with healthy control subjects, the concentrations of both phosphatidylcholine and phosphatidylethanolamine were significantly decreased in the antral gastric mucosa in all patient groups., Conclusions: NSAID use contributed to bleeding ulcers in 28.4% of patients; thus, low-dose aspirin or on-demand NSAID use may cause bleeding ulcers. There were only two (1.7%) confirmed cases of H. pylori-negative, non-NSAID ulcers.

There is an increasing amount of evidence suggesting that T cell deficiency contributes to tumor development. However, it is unclear whether T cell deficiency leads to liver and colon carcinogenesis. The aim of this study was to investigate the role of T cells on liver and colon carcinogenesis. Athymic F344/N Jcl-rnu/- (nu/nu) rats and euthymic F344/N Jcl-rnu/+(nu/+) rats were administered the carcinogen azoxymethane (AOM) at a dose of 15 mg/kg body wt once a week for 2 weeks. At 48 weeks after the second carcinogen treatment, the rats were sacrificed, and livers and colons were examined. Apoptosis and cell proliferation were evaluated by DNA fragmentation and proliferating cell nuclear antigen assays, respectively. Wild-type p53 and members of the Jun and Fos oncogene families were detected by Western blotting. AOM treatment induced 100% liver tumor and 63.6% colon tumor incidence in T cell-deficient nu/nu rats, compared with 0% and 38.5% incidence in nu/+ rats. T cell deficiency promoted the inhibitory action of AOM on apoptosis in both liver and colon at 48 weeks. In contrast, T cell deficiency increased cell proliferation after AOM treatment in both tissues. Wild-type p53 was reduced in both tissues of T cell-deficient rats. AOM treatment induced c-Jun and c-Fos expressions in the liver but increased only Fos B in the colon, whereas T cell deficiency enhanced c-Jun overexpression in the liver. These results suggest that T cell deficiency leads to liver carcinogenesis partly by a reduction in wild-type p53 and increasing c-Jun expression in AOM-treated rats.

Aim: The aim of this study was to investigate whether central nervous system-related feeding behavior regulates mucosal apoptosis in rat small intestines., Methods: The test solutions used in this study were an H(1) receptor antagonist (chlorpheniramine maleate), 2-deoxy-D-glucose, leptin, and 1-deoxy-D-glucosamine (2-amino-1,5-anhydro-2-deoxy-D-glucitol). Test solutions were injected into the third cerebroventricles of rats. Feeding behavior and jejunal apoptosis were evaluated both with and without truncal vagotomy. Intestinal apoptosis was evaluated by percentage fragmented DNA, electrophoresis, and TUNEL staining., Results: Chlorpheniramine and 2-deoxy-D-glucose elicited feeding, whereas leptin and 1-deoxy-D-glucosamine suppressed feeding. The test solutions, which elicited feeding (0.24 and 24 micromol/rat of chlorpheniramine and 2-deoxy-D-glucose, respectively), suppressed mucosal apoptosis in the rat jejunum 1 h after cerebroventricular infusion. In contrast, the test solutions, which suppressed feeding (8 and 24 micromol/rat of leptin and 1-deoxy-D-glucosamine, respectively), induced jejunal mucosal apoptosis 3 h after infusion. The effects of the test solutions on feeding behavior and changes in apoptosis were not affected by truncal vagotomy., Conclusion: The central nervous system, which regulates feeding behavior, might control intestinal function through the regulation of intestinal apoptosis.

Background: It has not been clearly demonstrated whether the ventromedial hypothalamus regulates intestinal cell growth. Ornithine decarboxylase is a key enzyme in polyamine synthesis, which plays an important role in intestinal mucosal growth. The aim of this study was to investigate whether bilateral ventromedial hypothalamus lesions affect mucosal cell growth. This was done by evaluating ornithine decarboxylase activity and apoptosis in rat small intestines., Methods: Bilateral ventromedial hypothalamus lesions were produced by thermocoagulation, done with rats under halothane anesthesia 7 days before the experiments. Rats with lesions were pair-fed with sham-operated rats. Total (truncal) vagotomy was performed before the development of ventromedial hypothalamus lesions. Ornithine decarboxylase activity and apoptosis were evaluated in the jejunal mucosa., Results: Ornithine decarboxylase activity in the jejunal mucosa increased significantly 1 week after the development of the bilateral ventromedial lesions, and was attenuated by truncal vagotomy. Apoptosis in the jejunal mucosa was suppressed in rats with ventromedial hypothalamus lesions. In contrast to the effect on ornithine decarboxylase activity, the truncal vagotomies had no effect on apoptosis in rats with lesions. Apoptosis increased in the sham-operated rats after 24-h and 48-h fasting. Apoptosis in the jejunal mucosa of rats with ventromedial hypothalamus lesions did not increase after 24-h fasting. After 48-h fasting, jejunal apoptosis increased in rats with lesions, but not markedly., Conclusions: The ventromedial hypothalamus may regulate cell growth in the intestinal mucosa partly through the vagal nerve; however, the vagal nerve was not related to intestinal apoptosis controlled by the ventromedial hypothalamus.

To clarify the suppression of postprandial blood glucose rise via alpha-glucosidase (AGH) inhibitory action by natural compounds, propolis was examined in this study. A single oral administration of propolis extract (50% methanol fraction on XAD-2 column chromatography) in Sprague-Dawley rats demonstrated a potent antihyperglycemic effect with the significant AUC(0-120 min) reduction of 38% at a dose of 20 mg/kg compared to that of controls. Among the active compounds isolated from the fraction, 3,4,5-tri-caffeoylquinic acid was found to be a prominent candidate that exerts the effect and shows a strong maltase-specific inhibition with an IC(50) value of 24 microM. In addition, the noncompetitive inhibition power apparently increased with the number of caffeoyl groups bound to quinic acid.

How dietary corn oil is involved in colon carcinogenesis and cancer development is poorly understood. The aim of this study was to investigate whether long-term dietary corn oil promotes colon cancer by inhibiting the tumor suppressor gene p53-mediated mitochondria-dependent apoptosis in azoxymethane (AOM)-treated rats. Male Sprague-Dawley rats were injected with AOM or with saline and fed on a basal diet or basal diet supplemented with 10% corn oil for 48 weeks. Colonic aberrant crypt foci (ACF) and tumors, including adenomas and carcinomas, were examined. Colonic apoptosis and cell proliferation were evaluated. Wild type (wt) p53 was analyzed using reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. In addition, Bcl-2, Bcl-xL, Bax, and Bak localized in the mitochondria were detected. Long-term dietary corn oil increased ACF in AOM-treated rats at 12 weeks and promoted colon cancer invasion at 48 weeks. Cancer invasion was not observed in the AOM-treated rats without dietary corn oil, although colon adenomas and cancers were detected. Apoptosis was decreased and cell proliferation was increased in the AOM-treated rats with dietary corn oil, compared with the AOM-treated rats with dietary basal diet. In these rats, mitochondrial wt p53 was significantly inhibited through decreased mitochondrial localization of wt p53 and increased cytosolic p53, resulting in the upregulation of Bcl-2 and Bcl-xL and the downregulation of Bak in the mitochondria. Results suggest that long-term dietary corn oil promotes AOM-induced colon cancer development partly by inhibiting the tumor suppressor gene p53-mediated mitochondria-dependent apoptosis.

Background: Tissue and organic venous congestion is a common pathophysiologic phenomenon. However, it is unclear whether venous congestion induces small-intestinal mucosal apoptosis. The aim of this study was to investigate whether venous congestion, or congestion followed by re-outflow, induced small-intestinal mucosal apoptosis, and whether tumor necrosis factor-alpha is involved in this apoptosis., Methods: Small-intestinal venous congestion was induced in rats by occlusion of the superior mesenteric vein with a micro-bulldog clamp. At the end of the congestive period, the clamp was released to facilitate congestion followed by re-outflow. The rats were injected with a neutral anti-tumor necrosis factor-alpha antibody (0.15 mg/kg) via the jugular vein for 30 min before venous congestion or congestion followed by re-outflow. Intestinal mucosal apoptosis was evaluated and tumor necrosis factor-alpha was assayed. The amounts of caspase-8, caspase-3, and cytochrome c were determined by Western blot analysis., Results: Our results showed that venous congestion and congestion followed by re-outflow significantly increased mucosal apoptosis, the amount of mucosal tumor necrosis factor-alpha, and the levels of caspase-8 cleavage and caspase-3 activation, but did not induce cytochrome c release from mitochondria to the cytosol. Pretreatment with an anti-tumor necrosis factor-alpha antibody significantly reduced mucosal apoptosis after intestinal congestion or congestion followed by re-outflow., Conclusions: The present results support the view that venous congestion and congestion followed by re-outflow induce mucosal apoptosis in the rat small intestine, and show that the apoptosis occurs partly via tumor necrosis factor-alpha-mediated cell death.

Ischemic preconditioning provides a way of protecting organs from damage inflicted with prolonged ischemia-reperfusion. In this study, we investigated the mechanism of ischemic preconditioning involved in inhibition of prolonged ischemia-reperfusion-induced mucosal apoptosis in rat small intestine. Ischemic preconditioning was triggered by a transient occlusion of the superior mesenteric artery followed by reperfusion. Ischemia-reperfusion was induced by 60-min occlusion of the superior mesenteric artery followed by 60-min reperfusion in the small intestine. Ischemia-reperfusion alone induced mucosal apoptosis and mitochondrial respiratory dysfunction via promoted reactive oxygen species generation, reduced mitochondrial glutathione oxidation, increased mitochondrial lipid peroxidation, reduced mitochondrial membrane potential, and enhanced release of cytochrome c from mitochondria to activate caspase-9 and caspase-6 in the small intestine. Pretreatment with 20-min ischemia followed by 5-min reperfusion significantly inhibited the prolonged ischemia-reperfusion-induced mucosal apoptosis by 30%. Ischemic preconditioning ameliorated mitochondrial respiratory dysfunction by 50%, reduced reactive oxygen species generation by 38%, and suppressed mitochondrial lipid peroxidation by 36%, resulting in improvement of the mitochondrial membrane potential and prevention of cytochrome c release as well as caspase-6 activation. Results suggest that ischemic preconditioning attenuated ischemia-reperfusion-induced mucosal apoptosis partly by inhibiting the reactive oxygen species-mediated mitochondria-dependent pathway in the rat small intestine.

The localization of leptin and leptin receptors in the stomach and small intestine has been reported. Their function is still unknown, although leptin is a hormone that regulates appetite and fat-related metabolism. The small intestine is one of the important organs for regulating metabolism. The purpose of the present study was to investigate whether leptin regulates apoptosis in the small intestinal mucosa. Intestinal apoptosis was evaluated by percent fragmented DNA, electrophoresis, TUNEL staining, and western blotting analysis of caspase-3. Mucosal apoptosis in the rat jejunum and ileum was evaluated at 0, 3, 6, 12, and 24 hrs after injection. Rats were tested after ad libitum feeding and 24-hr fasting to exclude the anorectic effect of leptin. Leptin was injected intraperitoneally (ip) at a dose of 200 microg/rat and infused into the rat third cerebroventricle (icv) at a dose of 8 microg/rat. Leptin at a dose of 8 microg/rat significantly induced intestinal apoptosis in the small intestine at 3 and 6 hrs after icv administration in both ad libitum feeding and 24-hr fasted rats. This increase in apoptosis was not attenuated by vagotomy. Intestinal apoptosis increased 12 and 24 hrs after ip injection of leptin at a dose of 200 microg/rat. The peak of the increase in apoptosis in icv rats appeared earlier than that in ip rats. Leptin induced jejunal and ileal mucosal apoptosis in the rat, indicating that leptin might control intestinal function through the regulation of intestinal apoptosis.

Platelet activating factor (PAF) is a proinflammatory lipid mediator for inflammatory response. It is unclear whether PAF is involved in the very complex process of ischemia-reperfusion (I/R) induced mucosal apoptosis in small intestine. Intestinal I/R was induced in rats intestine by 60 min occlusion of the superior mesenteric artery, followed by a 60 min reperfusion. I/R induced mucosal apoptosis and PAF activity but inhibited PAF-acetylhydrolase activity. Increases in interleukin-6 (IL-6) and decreases in IL-10 were observed. Western blot analysis showed that I/R induced expressions of platelet endothelial cell adhesion molecule-1 (PECAM-1) and Fas and Fas ligand (FasL) proteins, cleaved Bid, and enhanced the release of cytochrome c from mitochondria to activate caspase-9. Pretreatment of PAF antagonist BN-52021 attenuated these changes, except the increase in Fas. The results showed that I/R-inhibited mucosal PAF-acetylhydrolase activity resulted in an increase of activated PAF. The activated PAF increased the mucosal IL-6 and PECAM-1, enhanced the expression of FasL but not Fas, and led to the cleavage of Bid and the release of cytochrome c from mitochondria to activate caspase-9. This finding suggests that PAF promotes mucosal apoptosis after I/R in the rat small intestine partly through FasL mediating caspase-9 active pathway.

The aim of this study was to investigate whether the central nervous system regulates mucosal cell growth and apoptosis in the rat small intestine. Ornithine decarboxylase is a key enzyme for polyamine synthesis, which plays an important role in intestinal mucosal growth. The increase in ornithine decarboxylase activity in the duodenum just before a dark period was abolished by truncal vagotomy. An infusion of 2-deoxy-D-glucose into the third cerebroventricle activated the enzyme activity in the small intestine. Epithelial homeostasis is balanced by the regulation of cell proliferation and cell death. Intestinal mucosal apoptosis decreased in rats with ventromedial hypothalamus lesions, which induced hyperphagia and obesity. In contrast, sustained anorexia induced by 1-deoxy-D-glucosamine increased intestinal apoptosis. These results indicate that the central nervous system, in addition to local factors, is related to the regulation of mucosal homeostasis in the intestinal mucosa.

The aim of this study was to demonstrate (i) the role of iNOS (inducible nitric oxide synthase) on apoptosis in the rat intestinal mucosa after ischemia-reperfusion, and (ii) the effect of iNOS on the release of cytochrome c from mitochondria. The superior mesenteric artery was occluded for 60 min and was followed by a 60 min reperfusion. Rats were pretreated with an intraperitoneal injection of the following iNOS inhibitors: N-nitro-L-arginine methyl ester, aminoguanidine, and (1S,5S,6R,7R)-7- chloro-3-imino-5-methyl-2-azabicyclo [4. 1. 0] heptane hydrochloride (ONO-1714). Apoptosis was evaluated and NO(X) in the portal vein was assayed. The amount of iNOS, caspase-3, and cytochrome c were determined by a Western blot analysis. Intestinal mucosal epithelial mitochondrial dehydrogenase activity was assessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoilium bromide. Ischemia-reperfusion increased intestinal mucosal apoptosis, NO(X) production in the portal vein, the amount of iNOS protein, and the release of cytochrome c, but not caspase-3. Inhibitors of iNOS significantly attenuated the induction of apoptosis, increased NO(X) production, and release of cytochrome c. Mitochondrial dysfunction was induced by ischemia-reperfusion, which was ameliorated by iNOS inhibitors. Our results indicate that iNOS is related to increased mucosal apoptosis in the rat small intestine after ischemia-reperfusion, which is partly explained by the release of cytochrome c from mitochondria to cytosols following mitochondrial dysfunction.

Background: Phospholipids concentration in the gastric mucosa decreased in patients with Helicobacter pylori infection. The aim of this study is to examine the effects of eradication of H. pylori on decreasing the phospholipids concentration in the gastric mucosa in patients with gastric or duodenal ulcer., Materials and Methods: Phospholipids (phosphatidylcholine, phosphatidylethanolamine, and sphingonomyeline) were measured in biopsy specimens from the antrum and corpus using thin-layer chromatography. In H. pylori positive patients with gastric ulcer (n = 26) and duodenal ulcer (n = 13), and H. pylori negative controls (n = 20), the biopsy specimens were obtained before and 3 months after eradication. Eradication was performed using lansoprazole, amoxycillin, and clarithromycin., Results: Compared with the H. pylori negative control group, the concentrations of phosphatidylcholine and phosphatidylethanolamine decreased significantly in the gastric ulcer group in both antrum and corpus mucosa, and in the duodenal ulcer group in antrum mucosa. This decrease returned to the control level after eradication., Conclusions: This study demonstrates that the eradication of H. pylori in patients with peptic ulcer normalized the decrease of phosphatidylcholine and phosphatidylethanolamine in the gastric mucosa.

Both the ventromedial hypothalamus (VMH) and the mesencephalic trigeminal sensory nucleus (Me5) are densely innervated by histaminergic neurons. The depletion of neuronal histamine (HA) from the Me5 by the bilateral microinfusion of 448 nmol/rat alpha-fluoromethylhistidine (FMH), a specific suicide inhibitor of histidine decarboxylase, reduced the eating speed and prolonged meal duration, while leaving the meal size unaffected. HA depletion from the VMH increased the size of the meal and prolonged its duration, but not the eating speed. When the HA turnover rate was measured at 15 min after the scheduled feeding following fasting for less than 24 hr, the rate increased in the region including the Me5, but not in the hypothalamus. The turnover rate reached higher levels at 60 min in both regions. Gastric intubation of an isocaloric liquid diet or an equivolume of water with the liquid diet abolished the increase in HA turnover both in the Me5 region and the hypothalamus. The present findings indicate that brain HA thus modulates satiation through both the VMH and masticatory function as well as due to the action of the Me5. The HA function activated by mastication began earlier in the Me5 and later in the hypothalamus due to a signal originating from the oral proprioceptors and initiated by chewing.

Thirty-five monoclonal antibodies (MAbs) against glycoprotein (G protein) of the RC-HL strain of the rabies virus have been established. Using these MAbs, two antigenic sites (I and II) were delineated on the G protein of the RC-HL strain in a competitive binding assay. Of these, 34 MAbs recognized the epitopes on site II. Site II was further categorized into 10 subsites according to their patterns in a competitive binding assay. Each site II-specific MAb showed 5 to 23 nonreciprocal competitions. The reactivities of 35 MAbs to rabies and rabies-related viruses in an indirect immunofluorescent antibody test showed that six MAbs in group A binded to rabies and rabies-related viruses and eight MAbs in group E reacted only with rabies viruses, considering that the former represent the genus-specific of Lyssavirus and the latter are rabies virus-specific. From biological assays, 28 of the 35 MAbs showed neutralization activity, 31 showed hemagglutination inhibition (HI) activity, and 18 showed immunolysis (IL) activity. The MAbs recognizing neutralization epitopes fell into at least three groups: those exhibiting both HI and IL activity, those showing only HI activity, and those showing neither HI nor IL activity. All IL epitopes overlap with HA epitopes. Five of the nine MAbs which reacted with the antigen treated by sodium dodecyl sulfate in ELISA were not reduced, or reduced only slightly, in the titer. None of the MAbs reacted with 2-mercaptoethanol-treated antigen. Only one MAb that recognized site I reacted with the denatured G protein in a Western blotting assay, indicating that its epitope is linear. These results suggest that almost all of the epitopes on the G protein of the rabies virus are conformation-dependent and the G protein forms a complicated antigenic structure.

Changes in meal parameters of rats fed with different consistency of food were examined using hard and soft pellets. Meal size and eating speed of the first meal after 1800 h increased significantly in rats fed with soft pellets compared to those fed with hard pellets. Effects of histamine depletion on meals treated with hard or soft pellets were investigated after an intraperitoneal injection of 0.11 mmol/kg alpha-fluoromethylhistidine (FMH), a specific suicide inhibitor of the histamine synthesizing decarboxylase enzyme. When rats were fed with hard pellets, FMH significantly decreased eating speed and prolonged meal duration without affecting meal size. When rats were fed with soft pellets, FMH increased meal size and duration, but not eating speed. The meal parameter of eating speed was significantly decreased and meal size and duration were increased in obese Zuckers, a hereditary histamine-depleted animal model, when compared to their lean littermates. These results indicate that proprioceptive sensation from the oral cavity may regulate meal parameters through histaminergic neurons in the brain.

Effects of 6 weeks endurance training (5 days per week) under hyperoxia (60% O2 plus 40% N2) on serum and tissue lipid levels were investigated in male rats. Rats were divided into 4 groups: normoxia-control (NC), hyperoxia-control (HC), normoxia-training (NT), and hyperoxia-training (HT). NT and HT groups were run on a treadmill in a chamber at 20 m per min with a 6 degree gradient for 30 min. The chamber was perfused with hyperoxic gas. After training under hyperoxia, high density lipoprotein cholesterol (HDL-C) was higher (p less than 0.01) than in the normoxic condition, but there were no changes in serum lipids and glucose, or liver and aorta cholesterol. Skeletal muscle TG and liver glycogen in hyperoxic condition tended to show the higher values. Basal lipolysis of adipose tissue was increased (p less than 0.05) by hyperoxia, and decreased (p less than 0.01) by training, but there was no change of norepinephrine induced lipolysis in any group. The results suggest that endurance training or resting under hyperoxia induces increased HDL-C or lipolytic activity of adipose tissue. These effects might be caused by greater fat oxidation during exercising or resting under hyperoxia.

Activity of human triceps surae muscle (TS) during locomotion was investigated in relation to the muscle shortening and lengthening contractions. Length changes in the TS were presumed from its girth recorded using a mercury-in-silastic gauge wrapped around the muscle belly. The muscle girth during the stance phase resulted in three peaks corresponding to the actions of heel contact, weight support and toe kick. These peak heights were apparently larger than the girth level in the perpendicular standing posture. Three girth increases in running appeared in the process of ankle dorsiflexion. During walking, girth increases on weight support and toe kick were seen in the same phase. The TS through the stance phase is considered to always contract into a shortening state less than the muscle length in the perpendicular standing posture. These muscle activities are probably imposed to resist the muscle stretching. Therefore, it was suggested that the TS contracts eccentrically, with no lengthening contraction.

Heat production, oxygen consumption, and lipolysis in isolated interscapular brown adipocytes from the rat were investigated. Epinephrine, norepinephrine, and isoproterenol increased heat production in a concentration-dependent manner, showing, about 6-, 4-, and 5-fold higher effects than controls, respectively. The concentration of isoproterenol for threshold heat production and glycerol release were 10(-10) M and 10(-9) M, respectively. The fact that 10(-9) M isoproterenol increased heat production by about 3-fold while glycerol release had no effect at all indicates that calorimetry is more appropriate for investigation of brown adipocytes. At least the method is more sensitive than that of measuring glycerol release.