p53 and H-ras mutations and microsatellite instability in renal pelvic carcinomas of NON / Shi mice treated with N-butyl-N-(4-hydroxybutyl)-nitrosamine: different genetic alteration from urinary bladder carcinoma.

We previously reported p53 mutations to be frequent (greater than 70%), whereas both H-ras mutations and microsatellite instability (MSI) were infrequent (about 10%), in urinary bladder carcinomas (UBCs) and their metastatic foci in the N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN)-induced mouse urothelial carcinogenesis model. In the present study, an analysis of p53 and H-ras mutations as well as MSI was performed on 12 renal pelvic carcinomas (RPCs) and 8 metastatic or invading foci produced by the same experimental procedure. Histologically, 10 of the RPCs were transitional cell carcinomas and the remaining 2 were squamous cell carcinomas. p53 mutations were infrequent and only found in one primary RPC (8%), its metastatic foci and an invading lesion in another animal (in a total 2 of 12; 17%). H-ras mutations were slightly more frequent (found in 3 of 12 animals; 25%), 4 of 5 involving codon 44, GTG to GCG, not a hot-spot reported for human cancers. In two cases, H-ras mutations were confined to lung metastasis and not detectable in their primary RPCs. MSI analysis was available for 6 pairs of primary RPCs and their metastatic foci, and 4 animals (67%) had MSI at one or more microsatellite loci. Overall, the distribution of genetic alterations differed from that in UBCs produced by the same experimental protocol. The results thus suggest that different genetic pathways may participate in carcinogenesis of the upper and lower urinary tract due to BBN.

Prospectively performed modified D1 lymphadenectomy for clinically diagnosed mucosal, node negative gastric cancer: findings over the past decade.

Based on retrospective analyses demonstrating the low probabilities of both lymph node metastasis and recurrence of curatively resected mucosal gastric cancer, we have established criteria for modified D1 lymphadenectomy (lymphadenectomy in the perigastric region as well as along the left gastric artery) and performed this in a prospective manner. In this study, we evaluate our treatment strategy by reviewing the patients prospectively undergoing modified D1 lymphadenectomy. The clinicopathological characteristics and survival data of 138 patients who underwent modified D1 lymphadenectomy between 1987--when we first introduced endoscopic ultrasonography--and 1996 were analyzed. The criteria for modified D1 lymphadenectomy were mucosal, node negative gastric cancer by pre-operative and intra-operative examinations. Depth of invasion was correctly diagnosed in 80% of the patients. Among the resultant submucosal gastric cancer patients, the incidence of slight submucosal invasion was increased in the second half-period (78%) as compared with that in the first half-period (44%). Nodal involvement was observed in 4 patients (2.9%); all of them exhibited the depressed type with ulceration and a histologically high grade of gastric cancer. Because their metastasized lymph nodes were all confined to the perigastric region, surgical treatment resulted in no residual cancer macroscopically. No patients succumbed to gastric cancer within the median and mean follow-up periods of over 6 years. These results suggest that our modified D1 lymphadenectomy is an effective option for the pre-operatively and intra-operatively diagnosed mucosal, node negative gastric cancer which meets our criteria.

Induction of hepatocellular carcinoma with high metastatic potential in WS/Shi rats: discovery of an inbred strain highly susceptible to the liver carcinogen N-nitrosomorpholine.

We investigated the susceptibility of three inbred strains of rats to the hepatocarcinogen, N-nitrosomorpholine (NNM), to establish a spontaneous metastatic model of hepatocellular carcinoma (HCC). WS/Shi. SD/gShi, and F344/DuCrj rats were given 0.02% NNM in drinking water for 8 weeks and thereafter left without any treatment. The experiment ceased at week 20, because mortality markedly increased after this time point in WS/Shi rats. Liver weight was highest in WS/Shi rats among the three strains examined. The incidence of HCC was 15/15 (100%) in WS/Shi rats, 1/16 (6%) in SD/gShi rats, and 13/16 (81%) in F344/DuCrj rats surviving after NNM treatment. Metastasis to the lung was observed in HCC-bearing rats at an incidence of 13/15 (87%) in WS/Shi, 1/1 in SD/gShi, and 6/13 (46%) in F344/DuCrj. Four-week administration of NNM resulted in a significantly higher BrdU-labeling index of hepatocytes in WS/Shi rats than in the other strains. These findings indicated that WS/Shi is the most sensitive strain to NNM and may be the most suitable strain for use as a spontaneous metastatic model of HCC among the strains of rats examined in the present study.

Dual roles of peptic ulcer in the carcinogenesis or extension of early gastric cancer.

BACKGROUND: Early gastric cancer (EGC) often coexists with peptic ulcer. In this study we investigated the roles of peptic ulcer in the carcinogenesis and extension of gastric cancer. METHODS: The clinicopathological characteristics of EGC and peptic ulcer and their relationship, as well as that of the background intestinal metaplasia, were compared among the following three groups: patients with peptic ulcer only inside the EGC (Contained group, 53 patients); patients with peptic ulcer only outside the EGC (Separate group, 26 patients); and patients of EGC with no peptic ulcer (Absent group, 43 patients). RESULTS: In the Separate group, a male preponderance was observed (P = .006), and all EGCs developed in the middle or lower third of the stomach (P = .06). Most of the EGCs were an intestinal type of cancer with severe background intestinal metaplasia. Topographically, 88% of the peptic ulcers in the Separate group developed proximal to the EGC. On the other hand, in the Contained group, most EGCs developed in the middle third of the stomach with an intestinal/diffuse type ratio of 1:1. Peptic ulcers inside the EGC were significantly more shallow than those that developed outside the EGC (P = 0.008). Although the incidences of submucosal cancer were nearly the same among the three groups, the maximum cancer diameter tended to be increased in the Contained group compared to that in the Absent group, and the incidence of lymph node involvement tended to be higher in the Contained group (8%) as compared with the other two groups (4%-5%). CONCLUSIONS: These results suggest that peptic ulcer outside the EGC contributes to the development of the intestinal type of EGC, with the background of more severe intestinal metaplasia during the peptic ulcer healing processes, whereas peptic ulcer inside the EGC develops secondary to EGC and favors cancer extension and metastasis. Peptic ulcer associated with EGC can be considered to exert different biological roles in the carcinogenesis or extension of ECG according to the location of the peptic ulcer.

The FLS mouse: a new inbred strain with spontaneous fatty liver.

BACKGROUND AND PURPOSE: A new strain of mouse, named FLS (fatty liver Shionogi), which develops spontaneous fatty liver without obesity, was established by inbreeding. Morphologic, physiologic, and genetic characterization of the strain was done. METHODS: Characteristics of male FLS mice were compared with those of the sister strain, dd Shionogi (DS), which does not develop spontaneous fatty liver. A genetic cross experiment was performed by mating FLS with C3H/He/Shi mice. RESULTS: The hepatocytes of neonatal FLS mice contained fine lipid droplets throughout the lobules, and large lipid droplets appeared as mice aged. Liver triglyceride concentrations of FLS mice were fivefold higher than those of DS mice, but serum lipid concentrations and the lipoprotein profile did not indicate abnormalities. Higher plasma aspartate transaminase and alanine transaminase activities in FLS, compared with DS mice, suggested hepatocellular lesions. The genetic cross experiment suggested that the fatty liver formation is a complex polygenic trait. CONCLUSION: The FLS mice develop a progressive hepatic steatosis without obesity and diabetes. The FLS mouse might be a good model for investigating hepatic disorders accompanied by fatty liver unrelated to alcoholism or obesity.

Immunohistochemical analysis of PAI-2 (plasminogen activator inhibitor type 2) and p53 protein in early gastric cancer patients with recurrence: a preliminary report.

BACKGROUND: High levels of urokinase-type plasminogen activator (u-PA) were demonstrated in gastric carcinomas along with inhibitors of plasminogen activators (PAI-1 and PAI-2). They may influence the ability to invade and metastasize and therefore be of importance to the risk of recurrence of stomach neoplasms after curative operation. This also appears to be the case for p53 mutations and p53 protein overexpression. METHODS: Six patients, all differentiated cancer cases who developed recurrent disease 5-10 years after curative operations for early gastric cancers (recurrence group), were studied in comparison with 49 patients who had no recurrence more than 10 years after similar surgery (control group). The expression of u-PA, PAI-1, PAI-2 and p53 was compared immunohistochemically in the recurrence and control groups. RESULTS: The expression of PAI-2 was significantly more frequent in the recurrence group, being found in five (83.3%) patients vs eight (16.3%) in the control group. p53 was expressed in five (83.3%) patients in the recurrence group and in 15 (30.6%) in the control group; the rate was again significantly higher in the former. CONCLUSION: The results suggest that PAI-2 and p53 expressed in differentiated early gastric cancers are possible indices of the risk of recurrence.

Increased angiogenin expression in obstructive chronic pancreatitis surrounding pancreatic cancer but not in pure chronic pancreatitis.

We previously demonstrated the increased expression of angiogenin (ANG) in pancreatic cancer and its relation to cancer aggressiveness; however, the expression patterns and the roles of angiogenin in chronic pancreatitis are still unknown. We investigated the expression of ANG both in the tissues and in the sera of chronic pancreatitis patients (pure chronic pancreatitis) by using in situ hybridization, Western blot analysis, and enzyme-linked immunosorbent assay. In situ hybridization revealed no detectable ANG messenger RNA (mRNA) signals in all tissues of pure chronic pancreatitis and normal pancreas. Only a small amount of protein band expression was obtained in all of the protein lysates of pure chronic pancreatitis and normal pancreas. Accordingly, there was no significant difference between the mean serum ANG concentration of chronic pancreatitis patients (352.1+/-72.5 ng/ml) and that of healthy volunteers (357.6+/-45.2 ng/ml). By contrast, acinar cells and interstitial fibroblasts in the tissues surrounding pancreatic cancer showed increased ANG mRNA expression. Strong protein band expression was obtained in the protein lysates of pancreatic cancer surrounding tissue, and mean serum ANG concentration was increased in pancreatic cancer patients. These findings suggest that ANG expression is increased in pancreatic cancer surrounding tissue but is not increased in pure chronic pancreatitis, and that ANG is potentially involved in the pancreatic cancer microenvironment rather than the establishment of pure chronic pancreatitis.

Clonal analysis of isolated intestinal metaplastic glands of stomach using X linked polymorphism.

BACKGROUND: Monoclonal precancerous cells undergo successive biochemical and genetic changes during the multistep process of carcinogenesis in the gastrointestinal tract. Despite a high association with intestinal-type stomach cancer (differentiated adenocarcinoma of the stomach), the role of intestinal metaplasia is unclear in stomach carcinogenesis. AIMS: To study the clonality of intestinal metaplasia. METHODS: The clonality of 86 single intestinal metaplastic glands isolated by EDTA treatment from gastrectomy specimens from patients with cancer were investigated. The methylation sensitive restriction enzyme HpaII and polymerase chain reaction (PCR) were used to detect a polymorphic human androgen receptor gene locus linked to an inactive X chromosome. RESULTS: Forty one (48%) intestinal metaplastic glands were heterotypic (mixed cells of different allelic methylation) and 45 (52%) were homotypic (cell population of the same allelic methylation), while almost all the single pyloric glands were homotypic. Eleven of 13 intestinal metaplastic mucosae that were 6 mm in diameter contained glands that had originated from different cells. There were no strong relationships between clonal type and location or histological type of intestinal metaplasia. CONCLUSION: Intestinal metaplasia in general is not a lesion that arises or proceeds monoclonally.

F344/Shi rats bearing type b catalase-1 locus are sensitive to sodium L-ascorbate promotion of two-stage urinary bladder carcinogenesis.

Our previous data showed that F344/DuCrj and LEW/Crj rat strains bearing the type a catalase-1 locus (CS1a) are sensitive to the promoting activity of sodium L-ascorbate (Na-AsA) in 2-stage urinary bladder carcinogenesis, whereas ODS/Shi and WS/ Shi rat strains bearing the type b catalase-1 locus (CS1b) are resistant. In present study, we investigated the susceptibility of F344/Shi rats also bearing the CS1 to the Na-AsA-promoting effects on bladder tumor development. Male rats, 6 weeks old, were given 0.05% N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) in their drinking water for 4 weeks, then fed either basal diet supplemented with 5% Na-AsA or no chemicals for 32 weeks. The rats given BBN alone had a few small carcinomas in the urinary bladder. In contrast, animals administered BBN-Na-AsA had many large carcinomas. Administration of Na-AsA was associated with significant elevation of urinary pH and L-ascorbic acid. The results indicate that F344/Shi rats are sensitive to the promoting effects of Na-AsA on 2-stage urinary bladder carcinogenesis, and thus that the CS1 locus may not influence susceptibility to promotion.

Induction of glandular stomach cancers in Helicobacter pylori-sensitive Mongolian gerbils treated with N-methyl-N-nitrosourea and N-methyl-N'-nitro-N-nitrosoguanidine in drinking water.

An animal model of stomach carcinogenesis was established using Mongolian gerbils with N-methyl-N-nitrosourea (MNU) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) as the carcinogens. In addition, the sensitivity of these gerbils to Helicobacter pylori (H. pylori) was confirmed. One hundred and sixty specific pathogen-free male MGS/Sea animals, 7 weeks old, were treated with MNU in the drinking water (30 ppm for alternate weeks to give 10 weeks exposure, or 10 ppm or 3 ppm for 20 weeks continuous exposure), or given MNNG in the drinking water at 400 ppm or 200 ppm for 20 weeks, or orally inoculated with ATCC43504 H. pylori (1.7 x 10(8) CFUs/animal). Adenocarcinomas in the glandular stomach were found in 2 out of 12 effective animals (2/ 12) treated with 30 ppm MNU at week 20, although all were dead or moribund by week 30 due to MNU toxicity. At week 50, the incidences of gastric adenocarcinomas in groups treated with 10 ppm MNU, 3 ppm MNU, 400 ppm MNNG, and 200 ppm MNNG were 2/21 (9.5%), 1/23 (4.3%), 7/ 11 (63.6%), and 1/10 (10.0%). The lesions were generally well differentiated, although poorly differentiated adenocarcinoma was also found in a single gerbil in each of the 10 ppm MNU and 400 ppm MNNG groups. In control animals no tumors were found. In the infection study, the animals were killed at week 20, and H. pylori was detected in all cases, causing multiple erosions with marked inflammatory cell infiltration in the lamina propria and submucosa, and frequent formation of lymphoid follicles. Thus, MNU and MNNG in the drinking water induced neoplastic lesions in the glandular stomach epithelium of H. pylori-sensitive gerbils.

Peutz-Jeghers syndrome manifesting complete intussusception of the appendix and associated with a focal cancer of the duodenum and a cystadenocarcinoma of the pancreas: report of a case.

The unusual occurrence of an "inside-out" appendix reported here is a case of complete intussusception of the appendix of a 45-year-old woman with Peutz-Jeghers syndrome in whom the diagnosis of intussusception was made preoperatively. At laparotomy, the lead point of intussusceptum was revealed to be a Peutz-Jeghers syndrome polyp of the appendix. There was also a cystic lesion in the pancreas, and subsequent distal pancreatectomy revealed a cystadenocarcinoma of the pancreas. Two jejunal Peutz-Jeghers syndrome polyps and two duodenal Peutz-Jeghers syndrome polyps were found via intraoperative endoscopies. The duodenal polyps were endoscopically removed, whereas a jejunal wedge resection was performed for the adjoining jejunal polyps. One of the two duodenal polyps possessed an adenocarcinoma focus. To our knowledge, this is the first report of complete intussusception of the appendix caused by a Peutz-Jeghers syndrome polyp.

Endotoxin binding and elimination by monocytes: secretion of soluble CD14 represents an inducible mechanism counteracting reduced expression of membrane CD14 in patients with sepsis and in a patient with paroxysmal nocturnal hemoglobinuria.

Little is known about the role of peripheral blood mononuclear cells (PBMCs) in lipopolysaccharide (LPS) elimination. We studied the endotoxin elimination capacities (EEC) of PBMCs of 15 healthy volunteers, 13 patients with sepsis, and 1 patient suffering from paroxysmal nocturnal hemoglobinuria (PNH). Although expression of CD14, the best-characterized receptor for LPS to date, was reduced from 93.6% +/- 0.8% in healthy subjects to 50.5% +/- 6.5% in patients with sepsis and was 0.3% in a patient with septic PNH, EEC were found to be unchanged. There was no difference in the amount of tumor necrosis factor alpha (TNF-alpha) released by PBMCs of healthy donors and patients with sepsis. Anti-CD14 antibodies (MEM-18) completely suppressed EEC, binding of fluorescein isothiocyanate-labeled LPS to monocytes as determined by FACScan analysis, and TNF-alpha release in all three groups studied. The concentrations of soluble CD14 (sCD14) secreted by endotoxin-stimulated PBMCs from healthy donors and patients with sepsis amounted to 4.5 +/- 0.4 and 20.1 +/- 1.8 ng/ml, respectively. Based on our results, we suggest that PBMCs eliminate LPS by at least two different mechanisms; in healthy subjects, the membrane CD14 (mCD14) receptor is the most important factor for LPS elimination, while in patients with sepsis (including the septic state of PNH), increased sCD14 participates in LPS elimination. Secretion of sCD14 is strongly enhanced under conditions of low expression of mCD14 in order to counteract the reduction of mCD14 and maintain the function of monocytes. This sCD14 may substitute the role of mCD14 in LPS elimination during sepsis. The elimination of LPS by PBMCs correlates with the binding reaction and the secretion of TNF-alpha.

Infrequent involvement of microsatellite instability in urinary bladder carcinomas of the NON/Shi mouse treated with N-butyl-N-(4-hydroxybutyl)nitrosamine.

Variation in the frequency of microsatellite instability (MSI) has been reported in different kinds of human malignant tumors, with less than one-third of invasive urinary bladder carcinoma cases estimated to be affected. Here we investigated the MSI for 27 microsatellite sequences in invasive urinary bladder carcinomas of the NON/Shi mouse induced by N-butyl-N-(4-hydroxybutyl)nitrosamine. A total of 28 urinary bladder carcinomas of both transitional cell and squamous cell types were studied. All were invasive (greater than pT3) and high-grade and 10 of them had metastasis. Only two (11%) of 18 primary bladder carcinomas without metastasis foci showed alterations in one or two loci. None of 10 pairs of urinary bladder carcinomas and metastasis foci demonstrated any alterations. In conclusion, MSI which represents a defect in the DNA mismatch repair system is infrequent and therefore unlikely to be a critical step in genesis of invasive mouse urinary bladder carcinomas.

Helicobacter pylori promotes development of pepsinogen-altered pyloric glands, a preneoplastic lesion of glandular stomach of BALB/c mice pretreated with N-methyl-N-nitrosourea.

H. pylori is thought to be a stomach carcinogen. Since no experimental model has hitherto been established to clarify the relationship between H. pylori and stomach carcinogenesis, the effects of infection with the bacteria on experimental carcinogenesis in the glandular stomach of mice were investigated. BALB/c mice were given salty diet or N-methyl-N-nitrosourea (MNU) and administered broth culture of H. pylori. The incidence of pepsinogen-altered pyloric glands, considered as precancerous lesions, was increased in the H. pylori inoculated group pre-treated with MNU. The findings provide the new experimental model demonstrating the relationship between stomach cancer and H. pylori.

Genetic instability and p53 mutations in metastatic foci of mouse urinary bladder carcinomas induced by N-butyl-N-(4-hydroxybutyl)nitrosamine.

In a variety of human malignancies, alteration of the p53 tumour suppressor gene is known as a significant indicator of late progression events including invasion and metastasis, with a possible close relationship to genetic instability. Mutational analysis of the p53 and H-ras genes was performed for 10 pairs of N-butyl-N-(4-hydroxybutyl)nitrosamine-induced invasive mouse urinary bladder carcinomas and metastatic foci. p53 Mutations were found in nine of 10 (90%) primary carcinomas and seven of 10 (70%) metastatic foci. A total of eight p53 mutations in primary carcinomas were common in metastatic foci in six pairs. Additional p53 or H-ras mutations which were not identified in the primary carcinomas were found in three metastatic foci. Evaluation of the allelic distribution of the p53 mutations using RT-PCR, PCR and subcloning, further indicated possible intra-tumour genomic heterogeneity or excess copy numbers of the p53 gene due to genetic instability. Overall, p53 alterations were frequent in mouse urinary bladder carcinomas demonstrating progression. The results suggest that genetic instability might underlie generation of additional genetic alterations in this animal model.

A rare case of gastric cancer in an acromegalic patient.

Although it has been demonstrated that acromegalic patients have an increased risk of neoplasms, especially colon neoplasms, gastric cancer with acromegaly is very rare--only five cases have been reported to date in Japan. We report here a rare case of gastric cancer with acromegaly in a 58-year-old woman, whose acromegalic change began at age 44. This patient showed typical clinical features of acromegaly, with increased concentrations of blood growth hormone (GH) and insulin-like growth factor I (IGF-I); she had four types of neoplasms; gastric cancer, colon tubular adenoma with moderate atypia, pancreatic mucinous cystadenoma, and subcutaneous lipoma. The gastric cancer was macroscopically 0-IIc type, 3.0 x 2.5 cm in size, and histologically diagnosed as a poorly differentiated adenocarcinoma with limited invasion of the mucosal layer. The previously documented stimulatory effects of GH and/or IGF-I on tumorigenesis and cell proliferation may have been responsible for the development of the multiple neoplasms in our patient.

Efficacy of amino acid infusion for improving protein metabolism after surgery: a prospective randomized study in patients undergoing subtotal gastrectomy.

BACKGROUND: Appropriate regimens of peripheral parenteral nutrition (PPN) have been proposed for the improvement of protein metabolism after surgery. When evaluating the efficacy of administered nutrients, it is vital to consider the severity of surgical stresses to avoid confounding effects of the trauma on the postoperative metabolism. This study was designed to evaluate protein-sparing regimens through PPN in patients who had undergone subtotal gastrectomy. STUDY DESIGN: Patients hospitalized at our institutes for gastric cancer were randomly divided into the following five groups and received PPN for 7 days after surgery: 1. G group (n = 9), 200 g glucose (per day); 2. AG group (n = 10), 54 g amino acids + 150 g glucose; 3. AGG group (n = 9), AG + 110 g glucose; 4. AGF group (n = 10), AG + 40 g fat; and 5. AGL group (n = 7), 58 g amino acids + 60 g glycerol. Biochemical studies were done before and after surgery. RESULTS: In comparison to G group patients, AG group patients showed less negative cumulative nitrogen balances. No significant differences in cumulative nitrogen balances were observed between AGG, AGF, and AGL groups. Restoration of the reduced serum rapid turnover protein occurred earlier in the AGL group than in either the AGG or the AGF groups. Hyperglycemia, glucosuria, and hyperinsulinemia were prominent in the AGG group, and less prominent in the AGL group. Marked ketosis together with an increase in serum-free fatty acid levels was found in the AGL group. CONCLUSIONS: These results suggest that in patients who have undergone major elective surgery, infusion of amino acid solutions is advantageous for improving protein metabolism after surgery, and nonprotein energy source and intake are not essential when combined with amino acid solutions for improving nitrogen balance after surgery.

Flat cancers do develop in the polyp-free large intestine.

PURPOSE AND BACKGROUND: Qualitative and quantitative analysis of many flat early cancers that have been discovered during the last decade led us to recognize that a flat route of cancer development de novo is as important a route as the polypoid one. We aim to prove through a longitudinal study that these flat early cancers indeed develop in flat mucosa and not in an adenomatous polyp. METHODS: From January 1, 1990, to July 31, 1994, 554 patients underwent at least two colonoscopies. These patients consisted of 364 males, and average age was 59 years. We searched for flat early cancers developing in polyp-free colorectal mucosa on or after a second colonoscopy. Polyp-free mucosa here means an intestinal segment proved to possess no adenomatous polyp during the preceding colonoscopies, irrespective of the presence of polyps elsewhere. RESULTS: Four flat early cancers were found developing in polyp-free colonic mucosa in four patients. Average age of the patients was 67 years. Locations of the cancers were the transverse (3) and descending colons (1). The shapes were all depressed, and average size of the lesions was 11 mm. Two lesions were endoscopically resected, and two by surgery. CONCLUSION: These four depressed cancers developing in polyp-free mucosa show that flat early colorectal cancers do arise de novo and not from an adenomatous polyp having collapsed on itself.

Effect of glutamine on acute lung injury in rats with endotoxemia.

We administered endotoxin to rats to produce an acute lung injury model, and assessed the effect on respiratory function when glutamine was added to the solution for total parenteral nutrition. Rats given total parenteral nutrition with glutamine as 33% of the amino acid content were compared with rats given no glutamine. Endotoxin (500 microg/kg) was administered intravenously after 72 h of total parenteral nutrition. The survival rate and the nitrogen balance were significantly improved (P < 0.05) at 48 h after endotoxin administration as a result of glutamine treatment. In addition, the arterial oxygen partial pressure was significantly increased (P < 0.01) and the wet: dry lung weight ratio was decreased (P < 0.05) by glutamine. These results suggested that glutamine improved endotoxin-induced acute lung injury in rats.

Strain differences in sensitivity to the promoting effect of sodium L-ascorbate in a two-stage rat urinary bladder carcinogenesis model.

Rat strain differences in sensitivity to the promoting effect of sodium L-ascorbate (SA) on the development of urinary bladder tumors were investigated. In experiment 1, WS/Shi (WS), ODS/Shiod/od (ODS), and LEW/Crj (LEW) rats were initiated with 0.05% N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) in their drinking water and subsequently given basal Oriental MF diet (M) with or without a 5% SA supplement. In LEW rats the SA treatment increased the induction of neoplastic lesions in the urinary bladder, whereas WS and ODS animals proved unresponsive to its promoting effects. In experiment 2, WS and F344 rats were maintained on two kinds of commercial basal diets, M and CLEA CA-1 (C), during administration of SA, since dietary factors can influence promoting effects. Feeding M during the promotion period in F344 rats yielded significantly more neoplastic lesions than feeding C, but in WS rats no such dietary influence was apparent. In experiment 3, strain differences in biosynthesis of alpha-2u-globulin (alpha 1a-g) were assessed because both alpha 2a-g in the urine and administration of sodium salts of organic acids such as SA have been reported to be involved in tumor promotion. Immunohistochemical analysis of renal tubules and Western blotting analysis of urine revealed the presence of alpha 2a-g in all three strains examined. These data suggest that differences in susceptibility to promotion are due to genetic factors rather than dietary factors and the ability to synthesize alpha 2a-g.