Curva de crescimento em altura na cernelha de equinos da raça Mangalarga Marchador considerando-se heterocedasticidade / Growth curve for height at withers of Mangalarga Marchador horses with heterocedasticity

Objetivou-se, com este estudo, avaliar o ajuste dos modelos de Brody, Gompertz, Logístico e Von Bertalanffy aos dados de altura na cernelha de equinos Mangalarga Marchador, ponderando pelo inverso da variância, a fim de selecionar o melhor modelo e predizer sobre o crescimento e a maturidade dos animais dessa raça. Foram utilizados dados de 230 equinos dos seis aos 176 meses de idade, os quais foram divididos por sexo e em 16 classes de idade. Os modelos estudados foram comparados segundo os avaliadores de qualidade: coeficiente de determinação (R2); desvio padrão residual (DPR) e critério de informação de Akaike (AIC). A estimação dos parâmetros dos modelos foi realizada pelo método de mínimos quadrados ponderado no software R. Todos os modelos avaliados se mostraram adequados para descrever a curva de crescimento em ambos os sexos. Perante os avaliadores utilizados, o modelo Logístico foi o mais adequado para descrever as curvas de crescimento em altura na cernelha nos dois sexos da raça Mangalarga Marchador. Observou-se também um crescimento acelerado nos primeiros meses de idade. Os animais machos atingiram uma altura adulta maior, porém as fêmeas são mais precoces, pois apresentaram maior estimativa para o índice de maturidade.(AU)

This work aimed to evaluate the fit of models Brody, Gompertz, Logistic and Von Bertalanffy to height at the withers of Mangalarga Marchador horses, weighed by the inverse of variance, in order to select the best model and predict growth and maturity of this breed pf animals. We used data of 230 equines from 06 to 176 months of age who were divided by sex and 16 age classes. The models were compared according to the quality assessors: coefficient of determination (R2); residual standard deviation (RSD) and Akaike information criteria (AIC). The estimation of the parameters from models was performed by the weighted least squares method in Software R. All models evaluated were suitable to describe the growth curve in both sexes. In view of the evaluators used, the logistic model was the most suitable to describe the growth curves in withers height in both sexes for the race Mangalarga Marchador. A strong growth at first age was also observed. The males reached a greater adult height, but females did so sooner, because they presented higher estimates for the maturity index.(AU)

Alanyl-glutamine attenuates 5-fluorouracil-induced intestinal mucositis in apolipoprotein E-deficient mice

Apolipoprotein E (APOE=gene, apoE=protein) is a known factor regulating the inflammatory response that may have regenerative effects during tissue recovery from injury. We investigated whether apoE deficiency reduces the healing effect of alanyl-glutamine (Ala-Gln) treatment, a recognized gut-trophic nutrient, during tissue recovery after 5-FU-induced intestinal mucositis. APOE-knockout (APOE-/-) and wild-type (APOE+/+) C57BL6J male and female mice (N=86) were given either Ala-Gln (100 mM) or phosphate buffered saline (PBS) by gavage 3 days before and 5 days after a 5-fluorouracil (5-FU) challenge (450 mg/kg, via intraperitoneal injection). Mouse body weight was monitored daily. The 5-FU cytotoxic effect was evaluated by leukometry. Intestinal villus height, villus/crypt ratio, and villin expression were monitored to assess recovery of the intestinal absorptive surface area. Crypt length, mitotic, apoptotic, and necrotic crypt indexes, and quantitative real-time PCR for insulin-like growth factor-1 (IGF-1) and B-cell lymphoma 2 (Bcl-2) intestinal mRNA transcripts were used to evaluate intestinal epithelial cell turnover. 5-FU challenge caused significant weight loss and leukopenia (P<0.001) in both mouse strains, which was not improved by Ala-Gln. Villus blunting, crypt hyperplasia, and reduced villus/crypt ratio (P<0.05) were found in all 5-FU-challenged mice but not in PBS controls. Ala-Gln improved villus/crypt ratio, crypt length and mitotic index in all challenged mice, compared with PBS controls. Ala-Gln improved villus height only in APOE-/- mice. Crypt cell apoptosis and necrotic scores were increased in all mice challenged by 5-FU, compared with untreated controls. Those scores were significantly lower in Ala-Gln-treated APOE+/+ mice than in controls. Bcl-2 and IGF-1 mRNA transcripts were reduced only in the APOE-/--challenged mice. Altogether our findings suggest APOE-independent Ala-Gln regenerative effects after 5-FU challenge.

Vagotomy ameliorates islet morphofunction and body metabolic homeostasis in MSG-obese rats

The parasympathetic nervous system is important for β-cell secretion and mass regulation. Here, we characterized involvement of the vagus nerve in pancreatic β-cell morphofunctional regulation and body nutrient homeostasis in 90-day-old monosodium glutamate (MSG)-obese rats. Male newborn Wistar rats received MSG (4 g/kg body weight) or saline [control (CTL) group] during the first 5 days of life. At 30 days of age, both groups of rats were submitted to sham-surgery (CTL and MSG groups) or subdiaphragmatic vagotomy (Cvag and Mvag groups). The 90-day-old MSG rats presented obesity, hyperinsulinemia, insulin resistance, and hypertriglyceridemia. Their pancreatic islets hypersecreted insulin in response to glucose but did not increase insulin release upon carbachol (Cch) stimulus, despite a higher intracellular Ca2+ mobilization. Furthermore, while the pancreas weight was 34% lower in MSG rats, no alteration in islet and β-cell mass was observed. However, in the MSG pancreas, increases of 51% and 55% were observed in the total islet and β-cell area/pancreas section, respectively. Also, the β-cell number per β-cell area was 19% higher in MSG rat pancreas than in CTL pancreas. Vagotomy prevented obesity, reducing 25% of body fat stores and ameliorated glucose homeostasis in Mvag rats. Mvag islets demonstrated partially reduced insulin secretion in response to 11.1 mM glucose and presented normalization of Cch-induced Ca2+ mobilization and insulin release. All morphometric parameters were similar among Mvag and CTL rat pancreases. Therefore, the higher insulin release in MSG rats was associated with greater β-cell/islet numbers and not due to hypertrophy. Vagotomy improved whole body nutrient homeostasis and endocrine pancreatic morphofunction in Mvag rats.

Participation of the NO/cGMP/K+ATP pathway in the antinociception induced by Walker tumor bearing in rats

Implantation of Walker 256 tumor decreases acute systemic inflammation in rats. Inflammatory hyperalgesia is one of the most important events of acute inflammation. The L-arginine/NO/cGMP/K+ATP pathway has been proposed as the mechanism of peripheral antinociception mediated by several drugs and physical exercise. The objective of this study was to investigate a possible involvement of the NO/cGMP/K+ATP pathway in antinociception induced in Walker 256 tumor-bearing male Wistar rats (180-220 g). The groups consisted of 5-6 animals. Mechanical inflammatory hypernociception was evaluated using an electronic version of the von Frey test. Walker tumor (4th and 7th day post-implantation) reduced prostaglandin E2- (PGE2, 400 ng/paw; 50 µL; intraplantar injection) and carrageenan-induced hypernociception (500 µg/paw; 100 µL; intraplantar injection). Walker tumor-induced analgesia was reversed (99.3% for carrageenan and 77.2% for PGE2) by a selective inhibitor of nitric oxide synthase (L-NAME; 90 mg/kg, ip) and L-arginine (200 mg/kg, ip), which prevented (80% for carrageenan and 65% for PGE2) the effect of L-NAME. Treatment with the soluble guanylyl cyclase inhibitor ODQ (100% for carrageenan and 95% for PGE2; 8 µg/paw) and the ATP-sensitive K+ channel (KATP) blocker glibenclamide (87.5% for carrageenan and 100% for PGE2; 160 µg/paw) reversed the antinociceptive effect of tumor bearing in a statistically significant manner (P < 0.05). The present study confirmed an intrinsic peripheral antinociceptive effect of Walker tumor bearing in rats. This antinociceptive effect seemed to be mediated by activation of the NO/cGMP pathway followed by the opening of KATP channels.

Hind limb ischemic preconditioning induces an anti-inflammatory response by remote organs in rats

Ischemic preconditioning (IPC), a strategy used to attenuate ischemia-reperfusion injury, consists of brief ischemic periods, each followed by reperfusion, prior to a sustained ischemic insult. The purpose of the present study was to evaluate the local and systemic anti-inflammatory effects of hind limb IPC in male Wistar rat (200-250 g) models of acute inflammation. IPC was induced with right hind limb ischemia for 10 min by placing an elastic rubber band tourniquet on the proximal part of the limb followed by 30 min of reperfusion. Groups (N = 6-8) were submitted to right or left paw edema (PE) with carrageenan (100 µg) or Dextran (200 µg), hemorrhagic cystitis with ifosfamide (200 mg/kg, ip) or gastric injury (GI) with indomethacin (20 mg/kg, vo). Controls received similar treatments, without IPC (Sham-IPC). PE is reported as variation of paw volume (mL), vesical edema (VE) as vesical wet weight (mg), vascular permeability (VP) with Evans blue extravasation (µg), GI with the gastric lesion index (GLI; total length of all erosions, mm), and neutrophil migration (NM) from myeloperoxidase activity. The statistical significance (P < 0.05) was determined by ANOVA, followed by the Tukey test. Carrageenan or Dextran-induced PE and VP in either paw were reduced by IPC (42-58.7 percent). IPC inhibited VE (38.8 percent) and VP (54 percent) in ifosfamide-induced hemorrhagic cystitis. GI and NM induced by indomethacin were inhibited by IPC (GLI: 90.3 percent; NM: 64 percent). This study shows for the first time that IPC produces local and systemic anti-inflammatory effects in models of acute inflammation other than ischemia-reperfusion injury.

Vincristine delays gastric emptying and gastrointestinal transit of liquid in awake rats

We evaluated the effects of vincristine on the gastrointestinal (GI) motility of awake rats and correlated them with the course of vincristine-induced peripheral neuropathy. Vincristine or saline was injected into the tail vein of male Wistar rats (180-250 g) on alternate days: 50 µg/kg (5 doses, N = 10), 100 µg/kg (2, 3, 4 and 5 doses, N = 49) or 150 µg/kg (1, 2, or 5 doses, N = 37). Weight and stool output were measured daily for each animal. One day after completing the vincristine treatment, the animals were fasted for 24 h, gavage-fed with a test meal and sacrificed 10 min later to measure gastric emptying (GE), GI transit and colon weight. Sensory peripheral neuropathy was evaluated by hot plate testing. Chronic vincristine treatments with total cumulative doses of at least 250 µg/kg significantly decreased GE by 31-59 percent and GI transit by 55-93 percent. The effect of 5 doses of vincristine (150 µg/kg) on GE did not persist for more than 1 week. Colon weight increased after 2 and 5 doses of vincristine (150 µg/kg). Fecal output decreased up to 48 h after the fifth dose of vincristine (150 µg/kg). Vincristine decreased the heat pain threshold 1 day after 5 doses of 50-100 µg/kg or after 3-5 doses of 150 µg/kg. This effect lasted for at least 2 weeks after the fifth dose. Chronic intravenous vincristine treatment delayed GE and GI transit of liquid. This effect correlated with the peak increase in colon weight but not with the pain threshold changes.

Complex distribution of renal vessels

The retroperitoneal lumbar vessels should be immediately recognized during urological, vascular and radiologicalmedical procedures. Few studies have tried to define an exact pattern for the lumbar vasculature andmost of the anatomical descriptions suggest the presence of a regular pattern. Nevertheless, for the renal bloodvessels, despite the described regular pattern, several anatomical variations have interested anatomists for morethan a century. Taking into account that there is a constant need for reviewing this anatomy due to the advancesin surgical and/or uroradiological procedures techniques, we describe a complex variation of the renalblood vessels found during the dissection routine in our laboratory. A male cadaver, aged 65 years, embalmedwith 10% formalin solution presented, on the left side, two renal arteries arising from the abdominal aorta,both of them entering the kidney on the hilar region. From the hilar region of the left kidney, there were alsotwo tributary renal veins, which join together 3.0 cm from the hilus, before draining into the inferior venacava. These two tributary veins were large in diameter, and made a loop around the two renal arteries and alsothe ureter. No anatomical variations were found on the right side. This is a complex anatomical variation of therenal vessels which might have functional implications once the venous loop described might be a compressionfactor for the renal arteries and for the ureter.

Comparison of etoricoxib and indomethacin for the treatment of experimental periodontitis in rats

We investigated the effect of etoricoxib, a selective cyclooxygenase-2 inhibitor, and indomethacin, a non-selective cyclooxygenase inhibitor, on experimental periodontitis, and compared their gastrointestinal side effects. A ligature was placed around the second upper left molars of female Wistar rats (160 to 200 g). Animals (6 per group) were treated daily with oral doses of 3 or 9 mg/kg etoricoxib, 5 mg/kg indomethacin, or 0.2 mL saline, starting 5 days after the induction of periodontitis, when bone resorption was detected, until the sacrifice on the 11th day. The weight and survival rate were monitored. Alveolar bone loss (ABL) was measured as the sum of distances between the cusp tips and the alveolar bone. The gastric mucosa was examined macroscopically and the periodontium and gastric and intestinal mucosa were examined by histopathology. The ongoing ABL was significantly inhibited (P < 0.05) by 3 and 9 mg/kg etoricoxib and by indomethacin: control = 4.08 ± 0.47 mm; etoricoxib (3 mg/kg) = 1.89 ± 0.26 mm; etoricoxib (9 mg/kg) = 1.02 ± 0.14 mm; indomethacin = 0.64 ± 0.15 mm. Histopathology of periodontium showed that etoricoxib and indomethacin reduced inflammatory cell infiltration, ABL, and cementum and collagen fiber destruction. Macroscopic and histopathological analysis of gastric and intestinal mucosa demonstrated that etoricoxib induces less damage than indomethacin. Animals that received indomethacin presented weight loss starting on the 7th day, and higher mortality rate (58.3 percent) compared to etoricoxib (0 percent). Treatment with etoricoxib, even starting when ABL is detected, reduces inflammation and cementum and bone resorption, with fewer gastrointestinal side effects.

Effects of sample re-sequencing and trimming on the quality and size of assembled consensus sequences

The production of nucleic acid sequences by automatic DNA sequencer machines is always associated with some base-calling errors. In order to produce a high-quality DNA sequence from a molecule of interest, researchers normally sequence the same sample many times. Considering base-calling errors as rare events, re-sequencing the same molecule and assembling the reads produced are frequently thought to be a good way to generate reliable sequences. However, a relevant question on this issue is: how many times the sample needs to be re-sequenced to minimize costs and achieve a high-fidelity sequence? We examined how both the number of re-sequenced reads and PHRED trimming parameters affect the accuracy and size of final consensus sequences. Hundreds of single-pool reaction pUC18 reads were generated and assembled into consensus sequences with CAP3 software. Using local alignment against the published pUC18 cloning vector sequence, the position and number of errors in the consensus were identified and stored in MySQL databases. Stringent PHRED trimming parameters proved to be efficient for the reduction of errors; however, this procedure also decreased consensus size. Moreover, re-sequencing did not have a clear effect on the removal of consensus errors, although it was able to slightly increase consensus.

Comparative analysis of different DNA extraction protocols in fresh and herbarium specimens of the genus Dalbergia

Five published DNA extraction protocols were compared for their ability to produce good quality DNA from fresh and herbarium leaves of several species of the genus Dalbergia. The leaves of these species contain high amounts of secondary metabolites, which make it difficult to perform a clean DNA extraction and thereby interfering with subsequent PCR amplification. The protocol that produced the best DNA quality in most of the Dalbergia species analyzed, utilizes polyvinylpyrrolidone to bind the phenolic compounds, a high molar concentration of NaCl to inhibit co-precipitation of polysaccharides and DNA, and LiCl for removing RNA by selective precipitation. The DNA quality of herbarium specimens was worse than that for fresh leaves, due to collecting conditions and preservation of samples. We analyzed 54 herbarium specimens, but the recovered DNA allowed successful PCR amplification in only eight. For the genus Dalbergia, the herbarium is an important source of material for phylogenetic and evolutionary studies; due to the occurrence of the different species in various geographical regions in Brazil, it is difficult to obtain fresh material in nature. Our results demonstrated that for Dalbergia species the methods used for the collection and preservation of herbarium specimens have a mayor influence on DNA quality and in the success of phylogenetic studies of the species

A model of hemorrhagic cystitis induced with acrolein in mice

Acrolein is a urinary metabolite of cyclophosphamide and ifosfamide, which has been reported to be the causative agent of hemorrhagic cystitis induced by these compounds. A direct cytotoxic effect of acrolein, however, has not yet been demonstrated. In the present study, the effects of intravesical injection of acrolein and mesna, the classical acrolein chemical inhibitor, were evaluated. Male Swiss mice weighing 25 to 35 g (N = 6 per group) received saline or acrolein (25, 75, 225 æg) intravesically 3, 6, 12, and 24 h before sacrifice for evaluation of bladder wet weight, macroscopic and histopathological changes by Gray's criteria, and 3 and 24 h for assessment of increase in vascular permeability. In other animals, mesna was administered intravesically (2 mg) or systemically (80 mg/kg) 1 h before acrolein. Intravesical administration of acrolein induced a dose- and time-dependent increase in vascular permeability and bladder wet weight (within 3 h: 2.2- and 21-fold increases in bladder wet weight and Evans blue dye exuded, respectively, at doses of 75 æg/bladder), as confirmed by Gray's criteria. Pretreatment with mesna (2-mercaptoethanesulfonic acid), which interacts with acrolein resulting in an inactive compound, inhibited all changes induced by acrolein. Our results are the first demonstration that intravesical administration of acrolein induces hemorrhagic cystitis. This model of acrolein-induced hemorrhagic cystitis in mice may be an important tool for the evaluation of the mechanism by which acrolein induces bladder lesion, as well as for investigation of new uroprotective drugs.

Long-term ethanol intoxication reduces inflammatory responses in rats

The anti-inflammatory effects of long-term ethanol intoxication were determined during ethanol treatment and withdrawal on the basis of neutrophil and eosinophil migration, hind paw edema and mast cell degranulation. Male Wistar rats (180-200 g, around 2 months of age) were exposed to increasing concentrations of ethanol vapor over a 10-day period. One group was evaluated immediately after exposure (treated group - intoxicated), and another was studied 7 h later (withdrawal group). Ethanol inhalation treatment significantly inhibited carrageenan- (62 percent for the intoxicated group, N = 5, and 35 percent for the withdrawal group, N = 6) and dextran-induced paw edema (32 percent for intoxicated rats and 26 percent for withdrawal rats, N = 5 per group). Ethanol inhalation significantly reduced carrageenan-induced neutrophil migration (95 percent for intoxicated rats and 41 percent for withdrawn rats, N = 6 per group) into a subcutaneous 6-day-old air pouch, and Sephadex-induced eosinophil migration to the rat peritoneal cavity (100 percent for intoxicated rats and 64 percent for withdrawn rats, N = 6 per group). A significant decrease of mast cell degranulation was also demonstrated (control, 82 percent; intoxicated, 49 percent; withdrawn, 51 percent, N = 6, 6 and 8, respectively). Total leukocyte and neutrophil counts in venous blood increased significantly during the 10 days of ethanol inhalation (leukocytes, 13, 27 and 40 percent; neutrophils, 42, 238 and 252 percent, respectively, on days 5, 9 and 10, N = 7, 6 and 6). The cell counts decreased during withdrawal, but were still significantly elevated (leukocytes, 10 percent; neutrophils, 246 percent, N = 6). These findings indicate that both the cellular and vascular components of the inflammatory response are compromised by long-term ethanol intoxication and remain reduced during the withdrawal period.

Tortuosity of the internal carotid artery cervicalcourse: case reports and literature review

Variations in the course of the internal carotid arteries (ICA) are reported in the literature as coiling, looping,kinking or tortuosities of the vessels. Nevertheless, the definitions between these variants are confusing. Also, the clinical relevance of morphological anomalies of extracranial ICA is a matter of debate because of up to date the natural history of kinking, coiling and tortuosities of this artery is not well known. However, some authors consider that these conditions are burdened with disabling, even fatal neurological complications.Also, variations of the ICA cervical course may lead to direct contact of the artery with the pharyngeal wall, being of great clinical relevance due to the large number of routine procedures performed in this region. In the present study, we describe two cases of ICA tortuosities and review the current literature regarding the causes, symptoms and clinical significances of the variations of the cervical ICA course. Tortuosity of the cervical ICA is not a rare condition and they can easily be mistaken clinically for an aneurysm, a tumor or an abscess and subsequently injured during an attempted biopsy or excision. Thus, regardless the controversy of its causes (congenital or acquired) it should be included in the differential diagnosis of cervical soft tissue widening. Also, they should be taken into consideration on the diagnostic procedures for ischemic transitory attacks and/or stroke.

Low-dose doxycycline prevents inflammatory bone resorption in rats

Matrix metalloproteinases (MMP) are considered to be key initiators of collagen degradation, thus contributing to bone resorption in inflammatory diseases. We determined whether subantimicrobial doses of doxycycline (DX) (<=10 mg kg-1 day-1), a known MMP inhibitor, could inhibit bone resorption in an experimental periodontitis model. Thirty male Wistar rats (180-200 g) were subjected to placement of a nylon thread ligature around the maxillary molars and sacrificed after 7 days. Alveolar bone loss (ABL) was measured macroscopically in one hemiarcade and the contralateral hemiarcade was processed for histopathologic analysis. Groups of six animals each were treated with DX (2.5, 5 or 10 mg kg-1 day-1, sc, 7 days) and compared to nontreated (NT) rats. NT rats displayed significant ABL, severe mononuclear cell influx and increase in osteoclast numbers, which were significantly reduced by 5 or 10 mg kg-1 day-1 DX. These data show that DX inhibits inflammatory bone resorption in a manner that is independent of its antimicrobial properties

Pharmacological and histopathological study of cyclophosphamide-induced hemorrhagic cystitis - comparison of the effects of dexamethasone and Mesna

Chemotherapy with oxazaphosphorines, such as cyclophosphamide (CYP), is often limited by unacceptable urotoxicity. Without uroprotection, hemorrhagic cystitis (HC) becomes dose-limiting. To compare the uroprotective efficacy of classical 2-mercaptoethanesulfonic acid (Mesna) treatment with dexamethasone in CYP-induced HC, male Wistar rats (150-200 g; N = 6 in each group) were treated with saline or Mesna (40 mg/kg, ip) immediately and 4 and 8 h after ip administration of CYP (200 mg/kg). One, 2 or 3 doses of Mesna were replaced with dexamethasone (1 mg/kg, ip). The animals were sacrificed 24 h later. Cystitis was evaluated by determining the changes in bladder wet weight (BWW) and by macroscopic and microscopic analysis. CYP treatment induced a marked increased in BWW 162 percent 0.05, which was significantly inhibited by treatment with 3 doses of Mesna 0.05; 80 percent. The replacement of 1 or 2 doses of Mesna with dexamethasone reduced the increase in BWW by 83.3 and 95 percent, respectively. Macroscopic analysis of the bladder of rats with CYP-induced HC showed severe edema and hemorrhage, confirmed by microscopic analysis, that also showed mucosal erosion, inflammatory cell infiltration and ulcerations. The replacement of 1 or 2 doses of Mesna with dexamethasone inhibited the CYP-induced increase in BWW and almost abolished the macroscopic and microscopic alterations, with no significant difference between the effects of Mesna and dexamethasone, indicating that both drugs were efficient in blocking HC. However, although the replacement of all Mesna doses with dexamethasone reduced the edema, it did not prevent HC, suggesting that Mesna is necessary for the initial uroprotection

Histopathological analysis of rat mesentery as a method for evaluating neutrophil migration: differential effects of dexamethasone and pertussis toxin

In the present study, histopathological analysis of rat mesentery was used to quantify the effect of two anti-inflammatory agents, dexamethasone (Dex) and pertussis toxin (Ptx), on leukocyte migration. The intravenous injection of Dex (1 mg/kg) and Ptx (1,200 ng) 1 h prior to the intraperitoneal injection of the inflammatory stimuli lipopolysaccharide (LPS) or formyl-methionyl-leucyl-phenylalanine (fMLP) significantly reduced the neutrophil diapedesis (LPS: Ptx = 0.86 ñ 0.19 and Dex = 0.35 ñ 0.13 vs saline (S) = 2.85 ñ 0.59; fMLP: Ptx = 0.43 ñ 0.09 and Dex 0.01 ñ 0.01 vs S = 1.08 ñ 0.15 neutrophil diapedesis/field) and infiltration (LPS: Ptx = 6.29 ñ 1.4 and Dex = 3.06 ñ 0.76 vs S = 15.94 ñ 3.97; fMLP: Ptx = 3.85 ñ 0.56 and Dex = 0.40 ñ 0.16 vs S = 7.15 ñ 1.17 neutrophils/field) induced by the two agonists in the rat mesentery. The inhibitory effect of Dex and Ptx was clearly visible in the fields nearest the venule (up to 200 µm), demonstrating that these anti-inflammatory agents act preferentially in the transmigration of neutrophils from the vascular lumen into the interstitial space, but not in cell movement in response to a haptotactic gradient. The mesentery of rats pretreated with Dex showed a decreased number of neutrophils within the venules (LPS: Dex = 1.50 ñ 0.38 vs S = 4.20 ñ 1.01; fMLP: Dex = 0.25 ñ 0.11 vs S = 2.20 ñ 0.34 neutrophils in the lumen/field), suggesting that this inhibitor may be acting at a step that precedes neutrophil arrival in the inflamed tissue. In contrast to that observed with Dex treatment, the number of neutrophils found in mesenteric venules was significantly elevated in animals pretreated with Ptx (LPS: Ptx = 9.85 ñ 2.25 vs S = 4.20 ñ 1.01; fMLP: Ptx = 4.66 ñ 1.24 vs S = 2.20 ñ 0.34 neutrophils in the lumen/field). This discrepancy shows that Ptx and Dex act via different mechanisms and suggests that Ptx prevents locomotion of neutrophils from the vascular lumen to the interstitial space. In conclusion, the method described here is useful for quantifying the inflammatory and anti-inflammatory effect of different substances. The advantage of this histopathological approach is that it provides additional information about the steps involved in leucocyte migration.

Participation of TNF-Ó and IL-1 in the pathogenesis of cyclophosphamide-induced hemorrhagic cystitis

The involvement of cytokines TNF-Ó and IL-1 has been investigated in a model of cyclophosphamide (CYP) - induced hemorrhagic cystitis. Male Swiss mice (25-30 g) received CYP in a single ip dose of 100, 200 or 400 mg/kg and were sacrificed 6, 12, 24, 48 and 72 h later. Cystitis was evaluated by determining the changes in bladder wet weight (BW) and plasma protein extravasation (PPE, measured by the Evans blue leakage technique). CYP treatment induced a marked increase in BW and in PPE, which was significant within 6 h and reached maximal values within 12 h (BW, 118 percent, P<0.05; N = 11; and PPE, 824 percent, P<0.05; N = 11), continuing to be significant until 48 h. Pretreatment of animals with whole anti-TNF-Ó serum (25 or 50 µl diluted in 500 µl 0.9 percent saline, ip, 30 min earlier caused a significant reduction in the CYP-induced BW increase in 6-h and 12-h cystitis (82 percent and 91 percent, respectively, P<0.05; N = 6) and...

Tumor necrosis factor accounts for the neutrophil emigration activity released by cultured malignant fibrous histiocytoma cells

Cultured malignant fibrous histiocytoma (MFH) cells obtained from a spontaneous and transplantable rat tumor were studied for their ability to release tumor necrosis factor (TNF) and a factor which induces neutrophil migration in vivo. MFH cells obtained from 7-day cultures spontaneously released both activities into the supernatant (TNF: 36 ñ 9 iu tnf/ml supernatant, N = 3; neutrophil chemoattractant factor: control, Medium ip: 6 ñ 1 x 10**6; MFH supernatant: 18 ñ 1 x 106 neutrophils/cavity, H = 5). these releases were enhanced by treating MFH cells with LPS (TNF; 61 percent; neutrophil chemoattractant factor: 46 percent) and were abolished by the glucocorticoid dexamethasone (TNF: 68 percent; neutrophil chemoattractant factor: 100 percent). Anti-TNF antiserum abolished the neutrophil chemoattractant activity of the supernatants (95 percent). The release of TNF or neutrophil chemoattractant activity was reduced in cells obtained from older cultures (14 and 21 days) (TNF: 7-day culture, 36 ñ 9;14-day culture, 19ñ2;21-day culture, 19ñ 1 IU of TNF/ml; neutrophil chemoattractant activity: 7-day culture, 18 ñ 1.6; 14-day culture, 13 ñ 3;28-day culture, 8 ñ 1 x 10**6 neutrophils/cavity). The predominant cells present in 7-day cultures of MFH were histiocyte-like cells as determined by nonspecific esterase methods. The number of these cells decreased as the cultures aged (7-day culture, 71 percent; 14-day culture, 5 percent; 21-day culture, 0 percent)...