Unusual sex chromosomal DSD in a domestic Shorthair cat with a 37,X/38,XY mosaic karyotype.

BACKGROUND: Sex chromosome abnormalities associated with disorders of sexual development (DSD) are rarely described in cats, mainly due to the lack of chromossome studies that precisely reveal the condition. Genetic approaches are therefore required in order to detect sex chromossomes abnormalities as variations in the number and structure of chromosomes, or the presence of a second cell line as mosaicim or chimerism. CASE PRESENTATION: A male Shorthair cryptorchid cat was presented with clinical signs of anorexia, tenesmus and hyperthermia. Ultrasonography revealed a fluid-filled structure, with approximately 1 cm in diameter, adjacent to the descending colon. Computed tomography evidenced a tubular structure, ventral to the descending colon and caudal to the bladder, which extended cranially, through two branches. Histopathological evaluation confirmed the presence of two atrophic uterine horns and one hypoplastic testicle with epididymis at the end of one of the uterine horns. The end of the other uterine horn was attached to a structure composed by a mass of adipocytes. Cytogenetic analysis revealed a mosaic 37,X/38,XY karyotype. The two cell lines were found in 15% and 85% of the lymphocytes, respectively. Genetic analysis confirmed the presence of SRY and ZFY genes in blood and hair bulbs, and revealed a marked reduction in SRY expression in the testicle. Additionally, this case presented exceptionally rare features, such as a Leydig' cell tumour and a chronic endometritis in both uterine horns. CONCLUSIONS: Complete imaging workup, cytogenetic analysis and SRY gene expression should be systematically realized, in order to properly classify disorders of sexual development (DSD) in cats.

Influence of two collection frequency intervals on sperm quality of standard and miniature bull Terriers during short breeding periods: A clinical field study.

Background and Aims: The quality of canine sperm can be influenced by many factors, such as breed, body weight, age, ejaculatory frequency, nutrition, and environment. In the UK, it is common practice for standard Bull Terriers (SBT) and miniature Bull Terriers (MBT) to require male donors during a short breeding period. The aim of this study was to evaluate the effect of semen collection frequency on ejaculate volume and nine sperm parameters in SBT and MBT males, considering age and body condition score (BCS). Materials and Methods: Ejaculates from six adult SBTs and four MBTs were collected 5 times at two consecutive intervals (Time Series [TS]1, 24 h vs. TS2, 48 h), 1 week apart. Ejaculate volume, concentration, total output, viability (live sperm), subjective total motility, vigor, and total morphological defects, including head, midpiece, and tail defects of sperm, were evaluated. A multivariable mixed linear model for repeated measures was used to analyze the effects of semen collection frequency, age, breed, and BCS on ejaculate volume and sperm parameters. Results: Semen collection frequency, age, and, to a lesser extent, breed, and BCS significantly affected sperm parameters. Semen collection frequency affected all sperm parameters (p < 0.05) but not ejaculate volume (p > 0.05). Total sperm output, sperm vigor, total motility, and tail defects decreased (p < 0.05) at the end of TS1. However, sperm parameters remained relatively constant (p > 0.05) in TS2 between semen collection sessions. Overall, poorer sperm parameters were observed in older dogs (aged 5-8 years) than in younger dogs (aged 4 years). MBT produced less (p < 0.001) ejaculate volume (3.2 ± 0.2 mL vs. 4.3 ± 0.2 mL: Least Squares Mean ± Standard Error of Mean), lower total sperm output (221.8 ± 19.2 × 106 vs. 348.6 ± 19.2 × 106) and lower total morphological defects (25.0 ± 1.1% vs. 31.3 ± 0.9%), and a higher percentage of live sperm (77.0 ± 1.4% vs. 71.7 ± 1.1%) than SBT. In addition, a BCS of 4 positively influenced (p < 0.05) viability, vigor, and total sperm motility. Conclusion: Despite differences in age, breed, and BCS, better sperm parameter values were observed in all semen collection sessions. However, intensive semen collection (TS1) appears to be less effective in maintaining good sperm quality. For breeding or artificial insemination purposes, a 48-h interval between collection sessions is recommended for both breeds. The results of this study could be used to further optimize assisted reproductive technologies in both breeds.

Simultaneous Torsion of a Uterine Horn and Spleen in a Pregnant Two-Year-Old Crossbreed Bitch: A Case Report.

A pregnant 2-year-old mixed-breed dog was admitted with a 2-day history of lethargy, anorexia and painful abdominal distension. Clinical manifestations were unspecific and mainly suggested hypovolemic shock. Physical examination, ultrasonographic evaluation and radiographs confirmed mid-late pregnancy and evident signs of fetal death and peritoneal effusion. An exploratory laparotomy was immediately initiated which revealed torsion of the right gravid uterine horn over the left one and, simultaneously, the unexpected presence of splenic torsion and rupture, with a stretched omentum covering and exerting tension on the spleen's cranial pole. Histopathology revealed hemorrhagic infarction of the uterus and spleen. The animal recovered uneventfully and was later submitted to a preventive gastropexy.

The Comet assay for detection of DNA damage in canine sperm.

Sperm DNA integrity is a fundamental prerequisite in fertilization and embryo development. Among DNA integrity tests, the Comet assay is an accurate and sensitive test for the detection of sperm oxidative damage. The aim of this work was to evaluate sperm oxidative damage using the Comet assay and to study the correlation between Comet and routine assays for the evaluation of semen quality. Dogs were divided in two groups: group A (n = 6), comprising dogs with abnormal spermiogram, that is astheno-, terato- or oligoasthenoteratozoospermic (OAT); and group B (n = 8), comprising normospermic dogs. The distribution of sperm oxidative damage was significantly different between the two groups (p = .001): group A-median: 31.55%, interquartile range (IQR): 30.18-38.01; group B-median: 0.90%, IQR: 0.65-1.96. The correlation between oxidative damage and abnormal morphology was high (r = .846; p < .001). There was a negative correlation between progressive motility and oxidative damage (r = -.792; p = .001). Basal and oxidative DNA damage of spermatozoa are increased in dogs with non-normospermic semen. In conclusion, and considering the elevated correlation with classical tests of sperm quality, the Comet assay has ample potential for clinical and research purposes in dogs.

Interleukin-6 gene -174G>C and -636G>C promoter polymorphisms and prostate cancer risk.

Prostate cancer (PCa) is one of the most commonly diagnosed internal malignancies affecting men. Due to the important roles of IL-6 in different physiological and pathophysiological processes, IL-6 polymorphisms may modulate PCa risk. IL-6 -174 G>C (rs 1800795, also designated -236 G>C) and -636 G>C (rs 1800796, also designated -572 G>C) promoter polymorphisms have been implicated in PCa susceptibility, albeit still controversial. A literature search using PubMed and Highwire databases was conducted, resulting in eight case-control studies concerning the IL-6 -174 G>C polymorphism (11,613 PCa cases and 13,992 controls) and four case-control publications regarding the IL-6 -636 G>C polymorphism (1,941 PCa cases and 3,357 controls). In order to derive a more precise estimation, a meta-analysis based upon these selected case-control studies was performed. There was no significant association between IL-6 -174 G>C polymorphism and PCa increased risk. Nevertheless, the presence of allele C and the CC genotype were statistically significantly associated with decreased PCa risk in the overall analysis for IL-6 -636 G>C polymorphism. Additional studies in larger samples and analyses of functional repercussions of these SNPs in prostate tumor cells are necessary to validate these findings.

Population structure and genetic diversity of wild Helianthus species from Mozambique.

The production of sunflower suffered a major decline in Mozambique after its independence in 1975. Civil war, human activities and environmental damage subjected the species to an ecological stress contributing to reduce the number and size of wild populations. As this reduction is often related to a loss of genetic variation we estimated the genetic diversity within and among populations of wild Helianthus from five districts of Mozambique using RAPD markers. The 44 accessions studied grouped into four major clusters exhibiting structured variability with regard to geographic origin. A high level of genetic diversity (He = 0.350 and I = 0.527) was retained at the population level. The genetic variation among populations was high (59.7%), which is consistent with low gene flow (Nm = 0.338). The proportion of total genetic diversity residing among these populations should be kept in mind to devise different conservation strategies in order to preserve these populations. Currently wild Helianthus genetic resources present in Maputo and Sofala are on the edge of extinction mainly due to excessive urbanization. Therefore, conservation of what remains of this plant genetic diversity is essential for sustainable utilization and can be useful for breeding programs.

Functional density matrix formulation of quantum statistics.

We present a unified formulation for quantum statistical physics based on the representation of the density matrix as a functional integral. For quantum statistical (thermal) field theory, the stochastic variable of the statistical theory is a boundary field configuration. We explore the properties of an effective theory for such boundary configurations and apply it to the computation of the partition function of an interacting one-dimensional quantum-mechanical system at finite temperature. Plots of free energy and specific heat show excellent agreement with more involved semiclassical results. The method of calculation provides an alternative to the usual sum over periodic trajectories: it sums over paths with coincident end points and includes nonvanishing boundary terms. An appropriately modified expansion into modified Matsubara modes is presented.

Changes in the salivary biomarkers induced by an effort test.

Physical exercise induces biochemical changes in the body that modify analytes in blood and saliva among other body fluids. This study analyzed the effect of an incremental effort test on the salivary protein profile to determine whether any specific protein is altered in response to such stress. We also measured thresholds of salivary alpha amylase, total salivary protein and blood lactate and searched for correlations among them. Twelve male cyclists underwent a progressive test in which blood and saliva samples were collected simultaneously at each stage. The salivary total protein profile revealed that physical exercise primarily affects the polypeptide corresponding to salivary alpha-amylase, the concentration of which increased markedly during the test. We observed thresholds of salivary alpha-amylase (sAAT), total salivary protein (PAT) and blood lactate (BLT) in 58%, 83% and 100% of our sample, respectively. Pearson's correlation indicates a strong and significant association between sAAT and BLT (r= 0.84, P<0.05), sAAT and PAT (r= 0.83, P<0.05) and BLT and PAT (r= 0.90, P<0.05). The increased expression of the salivary alpha-amylase (sAA) polypeptide suggests that sAA is the main protein responsible for the increase in total protein concentration of whole saliva. Therefore, monitoring total protein concentration is an efficient tool and an alternative noninvasive biochemical method for determining exercise intensity.

Correlates of substance use during adolescent pregnancy in São Paulo, Brazil

Objetive: To investigate the association of cocaina and marijuana use during adolescent pregnancy in são paulo-sp, brazil with psychiatric disorders, social status and sexual history. method: one thousand pregnancy adolescents were assessed by using the composite international diagnostic interview, and sociodemographic and socio-economic questionnaire at the obstetric center of a public hospital in são paulo. Hair samples were collected for analysis. Results: the following data were associated with cocaine and/or marijuana use during the third trimester of the pregnancy: being younger than 14 year of agge, having a history of more than 3 sexual partners, and having psychiatric disorders, specifically, bipolar disordes, post-traumatic stress disorder, and somatoform disorder. Conclusion: in earlt adolescence pregnancy, having 3 or more sexual partners in the life for this population os significantly associated with the use of cocaine or marijuana during gestation. This association suggests that specific intervention programs should target these young women.(au) - en

Priapism secondary to perineal abscess in a dog - a case report.

A 7-year-old intact male Boxer was referred to our services at the Veterinary Teaching Hospital of the University of Trás-os-Montes and Alto Douro, suffering from a persistently erect penis (including the bulbus glandis) that had been exposed for several days. Radiographic and ultrasonographic examinations detected a 5.0 x 3.5 cm mass located dorso-laterally to the urinary bladder. The microbial culture of the mass revealed Staphylococcus spp. At that time, we suspected the involvement of an abscess in the origin of the priapism. Medical and surgical treatments were promptly instituted, which allowed for penile withdrawal into the prepuce; however, the resolution of the penile erection was not accomplished in the following days and penile amputation was required. Histological evaluation of the excised penis revealed extensive infarction of the erectile tissue of the pars longa and bulbus glandis, and also of the blood vessels of the penis. Following penile amputation and antimicrobial therapy, the animal fully recovered. Ultimately, the animal died as a consequence of gastric torsion. At necropsy, some lesions compatible with a previous perforation of the intestinal wall were recorded. The data gathered from the anamnesis, the physical and imaging examinations, along with the post-mortem findings, allowed us to conclude that in this clinical case the primary cause of priapism was a perineal abscess due to bowel perforation.

Parasitological diagnosis of canine visceral leishmaniasis: is intact skin a good target?

The objective of this study was to evaluate intact skin of seroreactive dogs as a possible target for the parasitological confirmation of canine visceral leishmaniasis (CVL). For this purpose, 394 dogs identified in serological surveys carried out in the metropolitan region of Belo Horizonte were studied. Blood was collected from all animals for serology and a tissue sample was obtained from two sites for parasitological diagnosis. Skin obtained from the ear and scapular region was simultaneously analyzed in 247 animals and lesion samples and ear skin were analyzed in 147 dogs. Leishmania parasites were isolated from 310 (78.7%) animals, and all isolates were identified as Leishmania chagasi. Simultaneous isolation from two sites was possible in 240 of the 310 animals, including ear and scapular skin in 151/247 (61.1%) and ear skin and skin lesions in 89/147 (60.5%). Ours results suggest that intact skin is one of the main target sites for the parasitological confirmation of CVL in seroreactive dogs.

Differences in preservation of canine chilled semen using different transport containers.

In the present study, the effect of three different containers in the preservation of dog chilled semen, during 24, 48 and 72h was evaluated. Weekly sperm pools of different dogs were obtained, during 10 consecutive weeks. Semen samples were diluted in egg-yolk-Tris-fructose extender and stored in a Styrofoam box, a common Thermos flask and an Equitainer. Progressive motility, morphology and sperm membrane integrity were examined in semen aliquots taken daily from each container during the 3 days of storage. Additionally, integrity of the acrosome and sperm plasma membranes, determined by PI/Fitc-PSA staining was assessed at 48 and 72h of storage. At 24h no differences were observed between the three containers for the evaluated parameters. At 48h samples kept in the Equitainer presented a higher progressive motility than samples kept in the Thermos. At 72h, progressive motility was higher in the Equitainer than in the other two containers. Only samples kept in the Equitainer maintained similar levels of progressive motility between 24 and 72h. Membrane integrity assessed by eosin-nigrosin deteriorated over the 72h period, whereas functional membrane integrity determined by the hypoosmotic swelling test was independently affected by type of container (the Equitainer) kept a higher percentage of sperm cells with intact membrane) and time of storage (a decrease of membrane integrity between 24 to 72h). Staining with PI-Fitc-PSA allowed the detection of differences between containers but not between the two studied storage periods (48 and 72h). The results indicated that the use of the Equitainer is preferable when transporting chilled dog semen for more than 48h.

Effects of taurine and hypotaurine supplementation and ionophore concentrations on post-thaw acrosome reaction of dog spermatozoa.

The aim of this work was to study of the effect of the amino acids (AA) taurine (T) and hypotaurine (H) and of different calcium ionophore concentrations on the ability of capacitated frozen-thawed dog sperm to undergo the acrosome reaction (AR). Fifteen ejaculates grouped into five pools were used. Sperm was frozen at a concentration of 80x10(6)sperm cells/mL in the Uppsala Equex extender (UE) supplemented with 25, 50 and 75mM of either AA. The UE extender without T or H was used as control. After thawing, sperm was capacitated with Canine Capacitation Medium for 20min. Sperm was then challenged with calcium ionophore A23178 at 0, 2.5 and 10microM concentration and evaluated for integrity of plasma and acrosome membranes after 5, 15 and 30min of incubation, utilizing PI/Fitc-PNA fluorescent staining and flow cytometry. Sperm cryopreserved in UE supplemented with 50mM T (UE 50T) had higher AR rates than sperm cryopreserved with UE 75T, UE 25H and UE 50H, but AR rates were similar to semen frozen with the control extender. Challenges with 2.5 and 10microM/L of calcium ionophore increased AR in frozen-thawed sperm incubated for 5, 15 and 30min. The combination of calcium ionophore concentration and incubation time resulting in the highest AR rate was 10microM and 15min.

High-intensity ultraendurance promotes early release of muscle injury markers.

OBJECTIVE: To evaluate the impact of high-intensity ultraendurance (HIU) cycling, using it as a possible way to understand muscle injury kinetics and blood immune cells' release during high-intensity prolonged exercise DESIGN: Male amateur triathletes enrolled during a cycling race of the International Bike Championship 800 km cycling relay (approximately 23 h). Each athlete alternately cycled 20-25 minutes until exhaustion and performed a total of approximately 200 km. RESULTS: Creatine kinase levels in blood reached a 300% rise in a sigmoidal pattern, while lactate dehydrogenase levels increased by 30-40% following a hyperbolic pattern. Aspartate aminotransferase and alanine aminotransferase levels increased by up to 250% and 140%, respectively. Liver injury markers such as alkaline phosphatase and gamma-glutamyltransferase remained stable. Platelets increased by 20-30% from pre-exercise, and there was no change in haematocrit during the race. White blood cells rose by nearly 200%. Leucocytes rose 210% during the race, with a major component coming from neutrophils, which increased more than 300%. Triacylglycerol levels were decreased at the finish and total cholesterol levels remained unchanged. Urate increased (by up to 35%) during the first half of the race, and urea levels increased with a different pattern, increasing by 45% in the second half. CONCLUSIONS: This study showed the blood appearance kinetics of muscle injury markers and some metabolites. It is suggested that the increase in these enzymes came primarily from muscle damage, rather than liver damage, and that white blood cells are selectively mobilised independently of haemoconcentration. The early appearance of muscle injury markers in this kind of exercise was also shown.

Incorporation of taurine and hypotaurine did not improve the efficiency of the Uppsala Equex II extender for dog semen freezing.

The working hypothesis of the present study was that supplementation of the Uppsala Equex II (UE) extender with the amino acid (AA), taurine (T) and hypotaurine (H) would improve dog sperm post-thaw quality, as previously seen for ram and bull semen, respectively. Five pools from 15 ejaculates of 15 dogs were used. Each AA was added to the UE extender at a concentration of 25, 50 and 7 5mM. Amino acid-free extender was used as a control. The following post-thaw parameters were evaluated: sperm motility by light microscopy and by CASA evaluation, longevity, viability (eosin-nigrosin staining), and flow cytometry (FC) was used to assess acrosome integrity and mitochondrial activity after PI/Fitc-PSA and PI-Rhodamine staining, respectively. Post-thaw sperm motility and velocity did not differ among extenders. Amplitude of lateral head displacement was lower for sperm frozen in the 25 mM H-supplemented extender. Semen frozen in the extender with 50 mM of T resulted in higher number of live sperm with damaged acrosomes after thawing. Higher numbers of live sperm with minimal mitochondrial activity were obtained for samples frozen with 25 and 50 mM T-supplemented extenders. Semen frozen in the control and 50 mM T-supplemented extenders had the highest number of live (eosin-nigrosin stain negative) sperm immediately post-thawing. We concluded that supplementation of the Uppsala extender with T or H did not improve sperm post-thaw mitochondrial activity or semen motility and viability.

Anti-inflammatory activity of four Bolivian Baccharis species (Compositae).

Hexanic, dichloromethanic, ethanolic and aqueous extracts from Baccharis obtusifolia HBK, Baccharis latifolia (R. et P.) Pers., Baccharis pentlandii D.C. and Baccharis subulata Wedd., plants used in the traditional medicine of South America have been studied for their in vitro anti-inflammatory activity in cellular systems. Calcium ionophore A23187-stimulated mouse peritoneal macrophages were validated as a source of cyclooxygenase-1 (COX-1) (prostaglandin E2, PGE2) and 5-lipoxygenase (5-LOX) (leukotriene C4, LTC4), and mouse peritoneal macrophages stimulated with Escherichia coli lipopolysaccharide (LPS) were used for testing cyclooxygenase-2 (COX-2) (PGE2), nitric oxide (NO) and tumour necrosis factor-alpha (TNF-alpha) activity. Most of the extracts tested were active in all assays.

[Cardiovascular morbidity in children with human immunodeficiency virus infection]. / Morbilidade cardiovascular em crianças com infecção pelo vírus da imunodeficiência humana.

UNLABELLED: Abnormalities of cardiovascular structure and function have been described among children with human immunodeficiency virus (HIV). In order to evaluate their occurrence and clinical predictors, 32 children infected with HIV, aged three months to 13 years (mean age = 3.11 +/- 3.51 years) were studied. Perinatal transmission was identified in 90% of the children. Twenty-two patients (pts) (69%) had symptoms, nine being moderately symptomatic and eight severely symptomatic. Fourteen pts had immunological disturbances and eight of them were severely immunosuppressed. Twenty-eight pts (88%) had HIV-1 infection and 6 recent Ebstein-Barr virus coinfection. Nineteen were on zidovudine and 14 on intravenous immunoglobulin treatment. Nineteen cardiovascular abnormalities were found in 15 pts (47%): 11 cases of pulmonary hypertension by echocardiographic criteria (eight of them had interstitial lung infiltrates seen on chest X-ray) and four cases of left ventricular dysfunction requiring anticongestive therapy. Other abnormalities were: patent ductus arteriosus, septal hypertrophy, mitral valve prolapse and pericardial effusion (one case each). Surface ECG displayed right ventricular hypertrophy in four pts, left ventricular hypertrophy in one patient and unspecific ST-T wave changes in two pts. Fourteen pts (44%) had sinus tachycardia with mean heart rate above the 95th percentile on 24-hour Holter monitoring. CONCLUSIONS: Cardiovascular abnormalities are frequent among children with HIV-1 infection in late stages; pulmonary hypertension is the most frequently found cardiovascular anomaly and seems to be related to either chronic or recurrent respiratory disease; cardiological follow-up is recommended for HIV-infected children.

Pindolol, not propranolol, reverses cardiac hypertrophy in renal hypertensive rats.

Reversal of cardiac hypertrophy has been obtained by treatment with some antihypertensive drugs but has not been achieved consistently with beta blockers. To investigate whether this difference might be explained by the distinct hemodynamic actions of the drugs, we studied the effects of propranolol and pindolol, beta blockers with distinct modes of action, on cardiac hypertrophy of hypertensive male Wistar rats, two-kidney, one clip (2K1C) Goldblatt model (n = 33) and sham-operated control rats (n = 34). We also assessed the effects of such therapies on the ventricular pumping ability during open-chest, transient aortic occlusion. Four weeks after surgery, propranolol (5 mg/kg/day p.o.) was given to hypertensive (n = 8) and control rats (n = 11); pindolol was also given orally (1 mg/kg/day) to similar groups (n = 7 and n = 5, respectively). Untreated animals served as controls for both groups. Cardiac hypertrophy developed with hypertension in the untreated rats of the propranolol (3.38 +/- 0.18 vs 2.60 +/- 0.08 mg/g; p less than 0.01) and pindolol groups (3.93 +/- 0.21 vs 2.40 +/- 0.03 mg/g; p less than 0.001). Treatment reversed cardiac hypertrophy in the pindolol-treated (3.01 +/- 0.19 vs 3.93 +/- 0.21 mg/g; p less than 0.001, NS) but not in the propranolol-treated rats (3.24 +/- 0.18 vs 3.38 +/- 0.21 mg/g, NS). The maximal pressure that developed during aortic occlusion in the propranolol group was similar to that observed in the pindolol group. These results indicate that cardiac hypertrophy is reversed by pindolol but not by propranolol, and that this reversal does not interfere with left ventricular pumping ability.

Consequences of reversal of hypertensive cardiac hypertrophy by captopril on left ventricular pumping ability and performance.

Left ventricular hypertrophy can be reversed by treatment of hypertension with captopril but the consequences of this regression are not yet fully described. We studied the maximal capacity of the hypertrophied and hypertrophy-reversed ventricle to generate pressure during transient total occlusion of the aorta, and also the left ventricular end-diastolic pressure required to meet this maximal effort. Two-kidney, one clip Goldblatt (renal hypertensive rats; RHR) hypertension was induced in 17 Wistar rats, eight of which were treated with captopril (RHR-C: 50 mg/kg given orally) from the fourth to the eighth week. Sham-operated controls (SC) remained untreated, or were treated with similar doses of captopril (SC-C). Significantly lower heart weights were found in RHR-C than in RHR (2.88 +/- 0.15 versus 2.38 +/- 0.04; P less than 0.001). During transient total occlusion of the aorta, the maximal intraventricular pressure developed in RHR-C was not significantly different from that in RHR, but left ventricular end-diastolic pressure was significantly less in RHR-C than in RHR (21.4 +/- 2.2 versus 34.3 +/- 3.8; P less than 0.01). The analysis of pressure-volume characteristics of the hypertrophied left ventricles and those in which hypertrophy was reversed revealed similar compliances between these two groups. Our data suggest that there was a mechanical improvement in the heart function after reversal of left ventricular hypertrophy.

Comparison of the hemodynamic effects of sodium acetate in euvolemic dogs and in dogs submitted to hemorrhagic shock.

We determined the dose-response relationship of systemic hemodynamics with graded intravenous infusions of sodium acetate (0.75, 1.50 and 3.00 microEq kg-1 min-1) in a group of dogs in the euvolemic state (N = 10) and in animals submitted to severe hemorrhagic shock (N = 7). Sodium acetate had a marked vasodilator effect on both groups, decreasing total peripheral resistance by 36.6% and 55.1%, respectively. Cardiac index increased simultaneously by 68.4% and 143.0%, respectively. Sodium acetate induced an approximate normalization of cardiac index and peripheral resistance at the highest infusion rate in the animals submitted to hemorrhagic shock. The normalization of cardiac output was due to a marked increase in heart rate in euvolemic dogs and to an increase in stroke volume in shocked animals. The hyperkinetic state of the circulation induced by the drug and a possible inotropic action of sodium acetate either direct or indirect could explain the different patterns of response.