Ethanol inhibition of compensatory ovarian hypertrophy in unilaterally ovariectomized rats

The purpose of this study was to determine the effect of ethanol consumption on compensatory ovarian hypertrophy (COH) which occurs following unilateral ovariectomy. Holtzman rats, 40 days old, were either unilaterally ovariectomized or sham-ovariectomized. The rats were then placed into subgroups which would receive either an ad libitum chow and water diet, a liquid diet, or a liquid diet containing 5% ethanol. The animals were maintained on their respective diets for 11 days. The rats were killed at 51 days of age, and the ovaries and uteri were removed, weighed, and prepared for histological investigation. The results showed that uteri from ethanol-fed animals failed to develop epithelial glands and exhibited a condensed stroma in comparison to uteri from animals fed ad libitum or pair-fed to ethanol-fed rats. Also, rats that were fed ad libitum had a COH of 82 +/- 16% and rats that were pair-fed a liquid diet had 114 +/- 28% COH; rats that were fed the liquid diet containing ethanol did not experience compensatory ovarian hypertrophy (-3 +/- 10%). Histologically, the ovaries of rats fed ad libitum showed large numbers of corpora lutea and only a few mature ova. The histology of ovaries from pair-fed animals was similar to those from animals fed ad libitum. In contrast, the ovaries from the animals fed the ethanol diet had nearly twice as many mature ova but only one-fourth as many corpora lutea as the number seen in ovaries from the other groups. The data show that ethanol consumption inhibits COH by suppressing ovulation and the subsequent luteal formation.     

Inhibition by bran of the colonic cocarcinogenicity of bile salts in rats given dimethylhydrazine

The effects of incorporating bile salts alone or bile salts and bran in the diet were investigated in 1,2-dimethylhydrazine (DMH)-induced intestinal carcinogenesis in rats. Male Sprague-Dawley albino rats were divided into the following groups: Group I, control; Group II, 0.5% mixed bile salts; Group III, 30 mg/kg DMH (10 weekly oral doses); Group IV, bile salts and DMH; and Group V, bile salts, 20% wheat bran and DMH. The bile salts and bran were added to a standard basal diet. The numbers of grossly observable colonic tumors/rat in Groups III, IV, and V were 10.8, 8.4, and 11.6, respectively. However, microscopic classification of these tumors revealed $\text{37}\text{46}$ malignant tumors in Group IV when compared to Group III ($\text{28}\text{68}$) and Group V ($\text{43}\text{77}$). Thus bile salts were cocarcinogenic but not cotumorigenic, that is, bile salts caused no increase in the number of grossly observable tumors, but rather potentiates the formation of malignant tumors. Bile salts alone increased the labeling index of epithelial cell nuclei in the lower third of the colonic cryts, while in combination with DMH, they increased the number of cells/crypt. Further, addition of bile steroids significantly increased the incidence and number of malignant duodenal tumors. No significant differences in the fecal excretion of acidic steroids were observed between Groups II, IV, and V.     

Effect of exogenous thyroxine on the development of the Purkinje cell in fetal alcohol effects in the rat

The amelioration of fetal alcohol effects on the postnatal development of the Purkinje cell by exogenous L-thyroxine was investigated in the neonatal rat. Time-pregnant rats were divided into three groups. Group A (n = 6) received 35% liquid ethanol diet; Group B (n = 6) was fed a liquid diet in which maltose dextrins replaced alcohol isocalorically, constituting the pair-fed group; Group C (n = 6) received the 35% liquid ethanol diet and, in addition, received exogenous thyroxine (5 microg/kg/day) subcutaneously. After the pups were born, the mothers were removed and the pups of each were surrogate fostered by dams who were fed normal rat chow and water ad libitum. An average of six pups, one from each litter, were killed at days 7, 14, 21, and 28 for each of the above three groups. Light and electron microscopic observations of lobule II/III revealed a delayed alignment of Purkinje cells (Pc) in alcohol-exposed pups compared to pair-fed pups. The Pc of the pair-fed group showed a single-layer arrangement at 7 days which was seen only at day 14 in the alcohol group. However, in the alcohol + T(4)-exposed pups a single-layer arrangement was quite often seen at 7 days. Morphological observations showed impaired evidence of protein synthesis at all time sequences in the pups of Group A compared to Group B. A most interesting finding was the morphological evidence of greater protein synthesis in the Pc of the alcohol + T(4) group at all times as indicated by a hypertrophied nucleus, abundant ribosomal collection, and numerous Nissl bodies.     

The effects of vitamin A, pentoxyfylline and methylprednisolone on experimentally induced amyloid arthropathy in brown layer chicks.

The effects of vitamin A, pentoxyfylline and methylprednisolone on experimentally induced amyloid arthropathy were investigated. In this study, 175 1-day-old brown layer chicks were used. Throughout the study Group II (vitamin A) received high doses of vitamin A (75,000 IU/kg), whereas Group I (negative control), Group III (positive control), Group IV (pentoxyfylline) and Group V (methylprednisolone) received normal levels of vitamin A in the diet. At the fifth week, the experimental Groups II, III, IV and V were injected with Freund's adjuvant intra-articularly to induce amyloid arthropathy. Group IV received pentoxyfylline and Group V received methylprednisolone (10 mg/kg, intramuscularly) once. Joint and blood samples were examined 13 weeks after the injections. The values in Groups I, II, III, IV and V, respectively, were as follows: amyloid arthropathy formation (%), 0, 100, 87, 76, 66; serum amyloid A (ng/ml), 166+/-17, 607+/-40, 423+/-39, 342+/-27, 293+/-22; serum retinol (microg/dl): 59.75+/-3.8, 42.72+/-3, 59.24+/-3.6, 102+/-9.1, 101.3+/-12.3; heterophil/lymphocyte ratio: 0.504, 0.75, 0.75, 0.087, 0.44. In conclusion, it was observed that vitamin A enhanced the development of amyloid arthropathy and there were positive associations between amyloidosis, increased levels of serum amyloid A and increased numbers of tissue infiltrating macrophages. Methylprednisolone had a more successful inhibitory effect on amyloid arthropathy than pentoxyfylline.     

Lack of fetal growth retardation in rats consuming alcohol prior to conception but not during gestation

A study was conducted to determine the effect of chronic alcohol consumption by female rats prior to conception but not during gestation upon fetal growth. The rats were divided into two dietary groups. Group 1 (alcohol) received ad libitum a stock diet plus ethanol in the drinking water. The ethanol concentration in the drinking water was 10% for the first week, 20% the second week and 30% during the next three weeks. Group 2 (pair-fed controls) received water ad libitum and the same amount of stock diet as that consumed by the ethanol group, but the ethanol was substituted isocalorically with corn starch. After five weeks on this regimen all animals were mated and the administration of alcohol was discontinued after conception. The maternal body weight gains were similar in the two dietary groups prior to and throughout gestation. No significant differences were seen between the alcohol and control groups with respect to litter size and fetal weight at day 21 of gestation, but the placentas were significantly heavier in the alcohol group. These results indicate that fetal growth retardation, which is characteristic of in utero alcohol exposure, is not induced when the period of alcohol intake is restricted to the time preceding gestation.     

Prenatal ethanol and the prepubertal sexually dimorphic nucleus of the preoptic area

The volume of the sexually dimorphic nucleus of the preoptic area of the hypothalamus (SDN-POA) was determined in 14-31-day-old male and female rats whose mothers received a liquid diet containing 5% w/v ethanol from day 8 of gestation to parturition. Pair-fed dams received as a nutritional control an equal volume of an isocaloric liquid diet with maltose-dextrin in place of ethanol. Normal controls had laboratory rat chow and water available ad lib. The SDN-POA volume of ethanol-exposed males was significantly reduced compared to the pair-fed and normal males, and became indistinguishable from the SDN-POA volumes of the pair-fed and normal females. Ethanol-treated females also had a markedly reduced SDN-POA volume compared to the pair-fed and normal females. Our findings indicate that the SDN-POA of prepubertal rats of both sexes is sensitive to the effects of in utero ethanol exposure. While plasma testosterone, progesterone and estradiol titers, which we measured in fetuses on gestation day 22, were differentially affected by maternal ethanol consumption, the alterations by themselves cannot adequately explain the effects of prenatal ethanol exposure on the developing SDN-POA.     

Anovulation in the prevention of cytotoxic-induced follicular attrition and ovarian failure

BACKGROUND: Gonadal failure secondary to alkylating agents may be related to ovulatory status. The objective of this investigation was to evaluate whether anovulation protected ovarian follicles during treatment with cyclophosphamide. METHODS: Four groups (n = 20 mature female Sprague-Dawley rats per group) were studied: control (group I), 5 mg/kg/day cyclophosphamide only (group II), 5 mg/kg/day cyclophosphamide and the combination of 50 micro g ethinyl estradiol/2 mg norgestrel (group III) and 5 mg/kg/day cyclophosphamide and 2.5 micro g leuprolide acetate daily (group IV). Animals were sacrificed after 4 weeks of treatment. Follicles were classified as medium (300-450 micro m) and large (>450 micro m) per section of ovary. RESULTS: Group II developed a significantly greater number of medium and large follicles [15.1 +/- 6.1 and 4.9 +/- 1.9 (mean +/- SD), respectively] compared with group I [7.1 +/- 2.1 and 1.0 +/- 0.7 (mean +/- SD), respectively] (P 相似文献   

Development of a Wound Dressing Composed of a Hyaluronic Acid Sponge Containing Arginine

Spongy sheets composed of cross-linked high-molecular-weight (HMW) hyaluronic acid (HA) were prepared by freeze-drying an aqueous HMW-HA solution containing cross-linking agent (Group I). The Group I sheet was immersed into an aqueous low-molecular-weight (LMW) HA solution with or without L-arginine (Arg) and was then freeze-dried to prepare several types of spongy sheets (Groups II–V). The amount of Arg was 1.0 g, 0.5 g, 0.2 g and 0 g in Groups III, IV, V and II, respectively. In the first experiment, each spongy sheet was applied to a full-thickness skin defect with a diameter of 35 mm in the abdominal region of SD rats, with intact skin in the central area measuring 15 mm in diameter. Commercially available polyurethane film dressing was applied over each spongy sheet as a covering material. The control group was covered with polyurethane film dressing alone. All spongy sheets promoted epithelization, as well as angiogenesis, as compared with controls. These findings indicate that HA and Arg are essential for wound healing. Re-epithelizaion was particularly active in Groups IV and V. In the second experiment, each spongy sheet was applied to a full-thickness burn injury measuring 35 mm in diameter in the abdominal region of SD rats, after necrotic skin was surgically removed. Groups II–V showed decreased wound size when compared with Group I and controls. The present findings indicate that the release of LMW-HA and Arg from a cross-linked HMW-HA spongy sheet effectively stimulates wound healing.     

Promotion of chemically induced rat esophageal tumorigenesis with post-initiation ethanol modification.

Post-initiation ethanol modification on N-nitrosomethylbenzylamine (NMBA)-induced rat esophageal carcinogenesis model was investigated in male, 6-week-old, F344 rats that received s.c. injections, 3 times per week, of 0.5 mg/kg NMBA for the first 5 weeks and then were treated with 0% (Group 1), 3.3% (Group 2), and 10% (Group 3) ethanol in the drinking water for up to 20 weeks. Group 4 received 10% ethanol without NMBA administration and Group 5 was maintained without any chemical treatment. There were no statistical differences in the incidence and multiplicity of esophageal tumors among Groups 1 to 3. However, the multiplicity of hyperplasias was statistically greater in Group 3 than in Groups 1 or 2. Esophageal epithelia of all rats in Groups 4 and 5 demonstrated a normal histology. BrdU labelling indices of tumors and hyperplasias in NMBA-treated groups were essentially similar, although cycline D1 was overexpressed to a greater extent in tumors and also hyperplasias of Group 3 than in Groups 1 or 2. The results indicated ethanol to exert weak promotion effects through cycline D1 overexpression on rat esophageal tumorigenesis initiated with NMBA.     

Atheroarteriosclerosis induced by infection with a herpesvirus.

Atheroarteriosclerosis closely resembling that in humans was induced in normocholesterolemic and hypercholesterolemic chickens by infection with Marek's disease herpesvirus (MDV). Four comparably sized groups of chickens were used. Each group was initially fed a diet relatively poor in cholesterol. Group I and II were inoculated intratracheally at 2 days of age with MDV. At 15 weeks, one group of virus-infected chickens (Group II) and one group of uninfected controls (Group IV) were fed a 2% cholesterol supplement for an additional 15 weeks. Group I, infected, and III, uninfected, were continued on a cholesterol-poor diet. All groups were killed at 30 weeks. Striking grossly visible atherosclerotic lesions were seen in large coronary arteries, aortas, and major aortic branches of both Groups I and II but not in those of Groups III and IV. Microscopically, arterial changes in infected animals were characterized by occlusive fibromuscular intimal thickening, which formed fibrous caps overlying areas of atheromatous change. This change closely resembled chronic atherosclerosis in humans. These results may be important to our understanding of human arteriosclerosis, since there is widespread and persistent infection of human populations with as many as five herpesviruses.     

Tetracarpidium conophorum Müll. Arg modulates sexual behaviour and biochemical parameters relevant to sexual function in male Wistar rats

Walnut (Tetracarpidium conophorum Müll. Arg) has been reported to be an essential ingredient in folklore medicine for sexual enhancement with little scientific validation. Hence, this study investigated the effects of walnut supplemented diet on sexual behaviour and biochemical parameters relevant to erection in male Wistar rats. Forty animals used in this study were divided into five groups (n?=?8); Group 1 – normal control rats fed with basal diet, Group II – rats fed diet supplemented with 10% processed walnut, Group III – rats fed diet supplemented with 10% raw walnut, Group IV – rats fed diet supplemented with 20% processed walnut and Group V – rats fed diet supplemented with 20% raw walnut. Behavioural studies (copulation tendency and anxiety) associated with sexual function, measurement of nitric oxide (NO) levels, adenosine deaminase (ADA), arginase and acetylcholinesterase (AChE) activities in the Corpus cavernosum as well as characterization of bioactive components of the nut were evaluated. Marked reductions in ADA and arginase activities and a concomitant increase (% inclusion dependent) in the level of NO as well as enhanced sexual behaviours were observed in rat fed supplemented walnut when compared to the control. Furthermore, analysis of the walnut using high performance liquid chromatography indicated the presence of some polyphenols. From our findings, it showed that walnut improves sexual behaviour and modulates activities of key enzymes relevant to erection in male rats which may justify its used in traditional medicine.     

Failure of angiotensin converting enzyme inhibition to affect the course of chronic puromycin aminonucleoside nephropathy.

The effects of the angiotensin converting enzyme (ACE) inhibitor enalapril on the proteinuria and degree of focal glomerular sclerosis hyalinosis (FSH) in chronic puromycin aminonucleoside nephropathy (PAN) were examined. Chronic PAN was induced in male Sprague-Dawley rats by seven subcutaneous injections of puromycin aminonucleoside (20 mg/kg) over 10 weeks (Groups I and II). Group II rats also received enalapril 10 mg/kg/day in the drinking water throughout the study (12 weeks). Group III rats served as age-matched controls. Proteinuria was similar in Groups I and II (35.5 +/- 9.7 versus 29.1 +/- 4.1 mg protein/mg creatinine, mean +/- SEM, P greater than 0.05). Serum creatinine remained unchanged in Group I, but rose from 0.7 +/- 0.04 to 1.2 +/- 0.1 mg/dl (mean +/- SEM, P less than 0.05) in Group II. FSH was 13.8% in Group I, 12.9% in Group II (P greater than 0.05), and 0.6% in Group III. There was no significant difference in glomerular lipid content and in immunofluorescence for rat albumin, fibrinogen, IgM, IgG, and C3 between Groups I and II. ACE activity was inhibited by 94% in serum, 83% in lungs, and 92% in kidneys; and blood pressure response to. Angiotensin I challenge was decreased by 50% in rats similarly treated with enalapril versus controls. In summary, proteinuria and glomerular sclerosis in this model are not affected by ACE inhibition.     

Effect of prenatal exposure to ethanol on the ultrastructure of layer V of mature rat somatosensory cortex

Summary Recent data have shown that the structure and function of layer V pyramidal neurons, e.g. corticospinal neurons, is altered by prenatal exposure to ethanol. We examined the effect of ethanol on the ultrastructure of layer V in somatosensory cortex. Timed pregnant rats were fed a diet containing 6.7% (v/v) ethanol (E) or pair-fed a nutritionally matched control diet (C). Thirty-day-old offspring of these mothers were prepared by standard electron microscopic techniques. The somata of pyramidal and local circuit neurons and the neuropil were analysed.Prenatal exposure to ethanol induced alterations in the somata of both populations of neurons. The parallel stacking of cisternae characteristic of C-treated rats was disorganized in E-treated rats. Moreover, the Golgi complex and lysosomes occupied a larger fraction of the somata of E-treated rats. The number and frequency of symmetric axosomatic synapses, but not asymmetric axosomatic synapses, formed by both types of neurons were significantly greater in E-treated rats. Gesta tional exposure to ethanol produced a variety of changes in the neuropil. Dendrites, particularly dendritic shafts, occupied less space in E-treated rats. In contrast, axons accounted for significantly more of the neuropil in E-treated rats than in controls. This increase in axonal space was due to a significantly greater coverage by non-myelinated axons and a significantly smaller coverage by myelinated axons in E-treated rats than in C-treated rats. Although the overall frequency of synapses was similar in both treatment groups, there were significantly more asymmetric synapses in E-treated rats, and most of these were axospinous synapses.These differences may contribute to documented physiological changes such as the lower rate of glucose utilization in layer V of somatosensory cortex of E-treated rats and they may underlie the mental retardation which is characteristic of children with foetal alcohol syndrome.     

Surfactant Therapy for Neonatal Respiratory Distress Syndrome: A Review of Korean Experiences over 17 Years

We undertook a multi-hospital collective study to evaluate outcomes of neonatal respiratory distress syndrome (RDS) patients treated with pulmonary surfactant (PS) over 17 yr in Korea (Group I; 1990/91, Group II; 1996, Group III; 2002, and Group IV; 2007). There were 60 neonates in Group I (16 hospitals), 1,179 in Group II (64), 1,595 in Group III (62), and 1,921 in Group IV (57). We adopted Bomsel''s classification to evaluate initial chest radiographic findings, categorized RDS severities, and classified response types to PS therapy. Almost all cases were treated using a single dose in Groups I and II, but 19.5% received multiple-dose therapy in Group IV. In Group IV, Bomsel''s stages III and IV composed 62.9% and initial severities of mild, moderate, and severe RDS were 23.0%, 42.0%, and 35.0%. More infants showed good response in Groups II, III, and IV than in Group I (71.7%, 66.8%, and 69.2% vs. 58.3%). Complications and mortality rate were lower in Group IV than in Groups I, II, and III (mortality rate: 14.3% vs. 40.0%, 30.0%, and 18.7%). We conclude that PS therapy in neonates with RDS had a remarkable impact on improving clinical course and outcomes over 17 yr in Korea.     

High-dose atorvastatin causes regression of endometriotic implants: a rat model

BACKGROUND: This prospective randomized-controlled animal study was designed to determine the effects of atorvastatin on experimentally induced endometriosis in a rat model. METHODS: Thirty-seven Wistar-Albino rats in which endometriotic implants were induced were randomly divided into four groups. Group I (Low-dose atorvastatin group, eight rats) were given 0.5 mg kg(-1) day(-1) oral atorvastatin. Group II (High-dose atorvastatin group, 10 rats) were given 2.5 mg kg(-1) day(-1) oral atorvastatin. Group III were given a single dose of 1 mg kg(-1) s.c. leuprolide acetate (GnRH agonist group, nine rats). Group IV were given no medication and served as controls (10 rats). All rats received the treatment for 21 days and were then euthanized to assess the implants' size, vascular endothelial growth factor (VEGF) level in peritoneal fluid and histological score. RESULTS: At the end of the treatment, the mean areas of implants were smaller and VEGF levels in peritoneal fluid were lower in Groups II and III than those in Group I and the control group (all P < 0.05). The mean areas of implants decreased from 41.2 +/- 13.9 to 22.7 +/- 13.9 mm(2) after medication in Group II and decreased from 41.2 +/- 18.1 to 13.1 +/- 13.8 mm(2) in Group III (both P < 0.05), whereas in Group I, the mean area increased from 43.0 +/- 12.7 to 50.5 +/- 13.9 mm(2) (P < 0.05). CONCLUSIONS: High-dose atorvastatin caused a significant regression of endometriotic implants.     

Prenatal loss in the rat following moderate consumption of alcohol incorporated in a liquid diet

The teratogenic potential of alcohol in humans has now been confirmed, and a characteristic pattern of anomalies (Fetal Alcohol Syndrome) is found in infants born to mothers who are chronic alcoholics. The pathogenesis of the fetal alcohol syndrome is unclear: very little is known about the way alcohol acts during pregnancy and alters fetal growth and morphogenesis. The objective of this investigation was to determine the effects of a widely used ethanol liquid diet in the pregnant rat. The ethanol liquid test diet is based on the Lieber-De Carli formula. 20 Sprague-Dawley rats were matched closely by weights and assigned in pairs to either an alcohol treated or a pair-fed control group. Control animals received the same amount of the liquid diet with maltose-dextrins substituted isocalorically for the ethanol. Graduated tubes were used for the oral delivery of the diets. Ethanol was gradually introduced into the diet as follows: 100 Kcal/l, days 1-2; 200 Kcal/l, days 3-5; 350 Kcal/l, days 6-12. Following this initial treatment period, all animals were then given rodent pellets and tap water ad libitum. The mothers showed no overt signs of gross toxicity. The mean maternal weight gain of the ethanol treated animals did not differ significantly from the controls. The incidence of fetal resorptions was increased, intrauterine growth was not affected and the offspring at term appeared normal. The results indicate that moderate alcohol consumption during early gestation in the rat led to significant prenatal loss but proved to be non-teratogenic.     

Behavioral and neuroanatomical effects of prenatal, postnatal, or combined exposure to ethanol in weanling rats

Separate and combined effects of prenatal and postnatal exposure to ethanol on activity, emotionality, learning, and hippocampal neuroanatomy were examined in infant rats. Neonatal rats from mothers that were fed either a liquid ethanol (E) or control (C) diet on Gestational Days (G) 1-21 were artificially reared during Postnatal Days (P) 4-12 on either 3% ethanol (E) or isocaloric maltose/dextrin (C) in a milk formula. Pups in these treatment groups (EE, EC, CE, and CC) were tested for activity and emotionally in an open field on P19, for acquisition and extinction of an appetitive, straight runaway task on P20-P21, and for the effects of ethanol treatments on alterations in hippocampal neuroanatomy on P21. Differences in activity and emotionally were slight. Ethanol affected both the partial reinforcement acquisition effect and the partial reinforcement extinction effect. Hippocampal cell density (compared with Group CC) showed a 12% reduction in CA1 pyramidal cells and an 11% reduction in mature granule cells in Groups EC and EE; the CA4 area (compared with Group CC) was significantly larger after postnatal exposure (Groups CE and EE). Significant positive correlations were found between rate of extinction after partial reinforcement (PRF) training and CA1 pyramidal cell density in Groups CC and CE. A significant negative correlation was found between extinction rate after PRF training and CA4 area in Group EE.     

Assessment of micronucleus frequency in the peripheral blood of female rats in persistent estrus treated with selective estrogen receptor modulators

The aim of this study was to evaluate micronucleus (MN) frequency in polychromatic erythrocytes (PCE) of female rats in persistent estrus (a model developed to mimic polycystic ovary syndrome) treated with selective estrogen receptor modulators (SERMs, tamoxifen, and raloxifene). Forty female Wistar-Hannover rats were divided into four groups of 10 animals each: Group I (normally cycling rats) and Group II (persistent estrus) both received only vehicle, while Group III (persistent estrus) was treated with tamoxifen (250 μg/animal/day) and Group IV (persistent estrus) was treated with raloxifene (750 μg/animal/day). Tamoxifen and raloxifene were given by oral gavage beginning on postnatal day 90 and continuing for 30 consecutive days. Peripheral blood samples were collected from tails 1 day following the last exposure. Blood smears were made on glass slides and stained with 10% Giemsa solution. ANOVA and a Tukey post-hoc test were used for data analysis. Mean percentages of MN were 1.82 ± 0.13, 5.20 ± 0.24, 3.32 ± 0.13, and 3.04 ± 0.12 in Groups I, II, III, and IV, respectively. The results indicate that tamoxifen and raloxifene similarly reduced the formation of MNPCE of female rats in persistent estrus (P < 0.0001 for Groups III and IV vs. Group II), using the dosages and time periods applied in the present study. The data suggest possibly antimutagenic effects of SERMs under high levels of estrogens. The findings also suggest that this is an interesting animal model for studying the genotoxicity of estrogens.     

Effect of cimetidine and carbenoxolone on cysteamine-induced ulcers: A study of gastric mucosal histamine and histamine formation capacity in rat

Cysteamine-induced ulcers in rat were used to study the effect of ulcer-healing agents with different modes of action on ulcer formation and mucosal histamine.Male Wistar rats were divided into 5 groups. Group I had cysteamine injection; group II had cimetidine followed by cysteamine injection; group III had carbenoxolone before cysteamine injection; group IV had carbenoxolone as group III and cimetidine and cysteamine injections; group V had saline injections (controls).In group I 20/29; group II 17/30; group III 15/29; and group IV 23/30 developed ulcers. No significant differences were found. No ulcers were found in group V. Comparison between all groups and controls showed an increase in gastric mucosal histamine and HFC. The increase in histamine was related to ulcer formation. Duodenal and oesophageal histamine did not change significantly. Gastric mucosal histamine and HFC were directly correlated.Neither cimetidine nor carbenoxolone alone or in combination prevent formation of ulcers following cysteamine administration. Cysteamine administration is followed by an increase in gastric mucosal histamine and HFC, which is not modified by cimetidine or carbenoxolone.     

Food restriction retards body growth and prevents end-stage renal pathology in remnant kidneys of rats regardless of protein intake

The objectives of this study were to evaluate the effects of food restriction (without protein or phosphorus restriction) and protein restriction (without the restriction of other nutrients or calories) on the outcome of the remnant kidney model of chronic renal failure in rats. After 5/6 nephrectomy, rats were assigned to one of the following dietary groups: group I (control-ad libitum) consumed a 21% casein diet ad libitum; group II (food restriction with protein restriction) consumed 36% less calories, protein and minerals than group I; group III (food restriction without protein restriction) consumed 36% less calories and minerals than group I, but equivalent amounts of protein; group IV (protein restriction) consumed 38% less protein than group I, but equivalent amounts of calories and minerals; group V (NaCl restriction) consumed 40% less sodium chloride than group I, but equivalent amounts of all other nutrients. All groups consumed equivalent amounts of calcium, phosphorus and vitamins. Groups II and III experienced retardation of growth in comparison to groups I, IV and V. The food-restricted groups II and III, but not groups IV and V, had less proteinuria than group I 20 weeks postablation. By 21 weeks postablation, the kidneys from group I showed severe parenchymal damage, characteristic of end-stage renal pathology. These changes were prevented in the food-restricted groups II and III, but not in groups IV and V. The percentage of glomeruli with severe structural damage was less in groups II (27.3 +/- 8.8) and III (26.9 +/- 7.5) compared with group I (72.4 +/- 7.8). In contrast, the corresponding values in groups IV and V were not significantly different from group I. Interstitial volume (the percentage of tubulointerstitium which is interstitium) which was proportional to the severity of tubular damage was significantly lower in groups II (25.1 +/- 4.5) and III (20.4 +/- 2.8) when compared with groups I (48.1 +/- 3.0), IV (44.4 +/- 6.6), or V (41.9 +/- 4.2). An interstitial volume less than 30 correlated with well preserved renal histology, whereas a value greater than 40 was indicative of end-stage renal pathology. These results indicate that the restriction of carbohydrate, fat, and minerals (except for calcium and phosphorus) retarded growth and prevented the development of end-stage renal pathology in the remnant kidney model of chronic renal failure in rats, regardless of whether protein was restricted or not.(ABSTRACT TRUNCATED AT 400 WORDS)