Glutamic Pyruvic Transaminase Values Research Articles

Effect of long term feeding of ammoniated wheat straw treated with or without HCl on blood biochemical parameters in growing male buffalo (Bubalus bubalis) calves

Twenty-four growing male buffalo calves (one year of age; 88.54 +/- 3.81 kg average body weight) were divided into three comparable groups (I, II and III) on the basis of their body weight (BW) in a completely randomised design to study the effect of long term feeding of ammoniated wheat straw (AWS) and hydrochloric acid treated ammoniated wheat straw (HCl-AWS) on blood biochemical changes. The animals were offered a concentrate mixture (CM) along with wheat straw (WS), ammoniated wheat straw (AWS) (4% urea at a 50% moisture level) and hydrochloric acid treated ammoniated wheat straw (HCI-AWS) (4% urea at a 50% moisture level and HCI added to trap 30% of NH3 evolved) in groups I, II and III, respectively for an average daily gain (ADG) of 500 g. All the diets were made iso-nitrogenous by preparing three types of concentrate mixtures of different CP levels. The blood was collected from the jugular vein randomly from three animals of each group initially after 8 months post feeding and subsequently after two months interval up to 14 months of experimental feeding. Due to urea ammoniation, the CP content of WS increased from 3.66 to 8.51 and was further increased to 11.35 due to the addition of HCl during urea-ammoniation of wheat straw. The cumulative period mean plasma glucose values (mg %), in group II (53.13) were significantly (P < 0.001) higher than those in groups I (48.44) and III (50.60). The cumulative period mean values of serum albumin and globulin (g %) were not significantly different and were comparable among the groups I (3.33 and 3.06), II (3.53 and 2.97) and III (3.49 and 2.94). The cumulative period mean values of serum albumin: globulin ratio and total protein values were not significantly different among the different groups. Serum urea and creatinine values were significantly (P < 0.001) higher in group III (58.66 and 2.24) as compared to groups I and II. The cumulative period mean values of serum alkaline phosphatase (ALP) (KA units) did not differ significantly, but serum glutamate pyruvate transaminase (SGPT) and glutamate oxaloacetate transaminase (SGOT) values (units x mL(-1) were significantly (P < 0.001) higher in groups II and III than in group I. The cumulative period mean values of T3 (ng x mL(-1)) did not differ significantly among the groups, but T4 values were significantly (P < 0.001) higher in group III (22.74) than in groups 1 (21.41) and II (20.89), respectively. Since the mean values of all the blood parameters were within the normal range, it may be concluded that feeding of ammoniated wheat straw treated with and without HCl to growing male buffalo calves for fourteen months has no adverse effect on the blood biochemical parameters.

Effects of microcrystalline plant sterol suspension and a powdered plant sterol supplement on hypercholesterolemia in genetically obese Zucker rats.

Because dietary fat appears to be an effective vehicle for dispensing plant sterols into the diet, a special plant-sterol-containing ingredient has recently been developed. This ingredient is a plant sterol suspension in oil in which the sterols are in microcrystalline form. The objective of the present study was to analyse the cholesterol-lowering effects and safety of two different plant sterol preparations, an orally administered microcrystalline plant sterol suspension (MPS) in rapeseed oil and a powdered plant sterol supplement, in obese Zucker rats. Dietary plant sterol supplements (0.5%, w/w) were given concurrently with a high cholesterol diet (HCD, 1% cholesterol and 18% fat, w/w). No significant changes in serum triglyceride, blood glucose, serum glutamate oxaloacetic transaminase and glutamic pyruvic transaminase values or body and liver weights were observed. The powdered plant sterol supplement lowered the serum cholesterol by 25% (P < 0.05) and the MPS diet by 35% (P < 0.001) compared with HCD by the end of the 12-week experiment. Interestingly, the plant sterol supplements also produced a marked reduction in serum ubiquinone levels, suggesting a possible effect on isoprene synthesis. Unlike the powdered plant sterol, both MPS and plain rapeseed oil decreased the serum baseline diene conjugation values, suggesting that they protect against oxidative stress-induced lipid peroxidation in rats. This lipid peroxidation diminishing effect is probably due to some antioxidative components in rapeseed oil. These findings indicate that an unesterified plant sterol, such as the microcrystalline suspension in oil, effectively prevents cholesterol absorption in obese Zucker rats.

Effect of benzene exposure on hematology and hepatic drug metabolic enzymes in ethanol administrated rats

There are few reports regarding the effects of benzene and ethanol being administered simultaneously. In our experiments with 4 groups (controls, ethanol, benzene and ethanol plus benzene) Wistar male rats were treated with ethanol (20%) for 5 weeks, and then exposed to benzene (0.26 g/kg) for 5 days per week for 3 weeks. We also investigated the effects of benzene on the body weight, organ weight, peripheral hematology and hepatic drug metabolizing enzymes in the ethanol administrated rats. The liver weight increased significantly, but spleen weight decreased significantly in the benzene exposed group. Hematological examination showed a decrease of leukocyte in the two groups of benzene and ethanol plus benzene in comparison with the controls, but an effect promoted by ethanol was not found. Serum glutamate oxaloacetate transaminase (SGOT) and serum glutamate pyruvate transaminase (SGPT) values were not significantly different in the exposure groups when compared with the controls. The contents of microsomal cytochrome P450 in all the exposed groups showed a tendency to increase, but they were not significantly different in comparison with the controls. On the other hand, hepatic glutathione S-transferase activity in the exposed groups increased significantly.

Modification of cellular immune responses in experimental autoimmune hepatitis in mice by maitake (Grifola frondosa)

Immune response to liver-specific lipoprotein (LSP) is involved in the pathogenesis of chronic active hepatitis. Experimental hepatitis could thus be prepared in C57BL/6 mice by injection of liver-specific protein in a syngeneic liver homogenate with Freund's complete adjuvant. In hepatitic mice treated with maitake (Grifola frondosa) fruit bodies, the values of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) values increased temporarily by 2.24–2.79 times and decreased rapidly thereafter. However, in the mice given normal feed, both values increased constantly. Thus, we examined T cell activities both in the exacerbation and remission stages of hepatitis. We suggest that the activation of CD8+ cells is more potentiated than that of CD4+ cells by administration of maitake or the D-Fraction-glucan (β-1,6 glucan having β-1,3 branches), which can enhance immuno-competent cells at the exacerbation stage. However, at the remission stage, marked potentiation of CD8+ cell activity was not observed. These results suggest that depressed suppressor T cell activity is revived by the X-Fraction-glucan (β-1,6 glucan having α-1,4 branched glucan), while the cytotoxic T cell activity, which is activated by the D-Fraction, is restricted, thereby creating a smooth shift from the exacerbation stage to the remission stage.

Carbapenem-induced endotoxin release in gram-negative bacterial sepsis rat models.

The carbapenem-induced endotoxin release was evaluated using experimental models of gram-negative bacterial sepsis in Wistar rats. Infections with Escherichia coli, Serratia marcescens, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus vulgaris and Proteus mirabilis resulted in an increase of the plasma endotoxin concentration after treatment with ceftazidime and carbapenems including imipenem, panipenem, meropenem and biapenem. Except for P. aeruginosa, the plasma endotoxin concentrations after carbapenem treatment were significantly lower than those after ceftazidime treatment. It is noteworthy that treatment of P. aeruginosa sepsis with meropenem or biapenem induced significantly more endotoxin release than other carbapenems and the endotoxin concentrations induced by these carbapenems reached those of ceftazidime treatment. The plasma endotoxin concentrations appeared to correlate with the reduction of platelet counts and the elevation of both glutamic oxaloacetic transaminase and glutamic pyruvic transaminase values.

Carbapenem-induced endotoxin release in Gram-negative bacterial sepsis rat models

The carbapenem-induced endotoxin release was evaluated using experimental models of Gram-negative bacterial sepsis in Wistar rats. Infections with Escherichia coli, Serratia marcescens, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus vulgaris and Proteus mirabilis resulted in an increase of the plasma endotoxin concentration after treatment with ceftazidime and carbapenems including imipenem, panipenem, meropenem and biapenem. Except for P. aeruginosa, the plasma endotoxin concentrations after carbapenem treatment were significantly lower than those after ceftazidime treatment. It is noteworthy that treatment of P. aeruginosa sepsis with meropenem or biapenem induced significantly more endotoxin release than other carbapenems and the endotoxin concentrations induced by these carbapenems reached those of ceftazidime treatment. The plasma endotoxin concentrations appeared to correlate with the reduction of platelet counts and the elevation of both glutamic oxaloacetic transaminase and glutamic pyruvic transaminase values.

Cholinesterase Status of Some Ethiopian State Farm Workers Exposed to Organophosphate Pesticides

Cholinesterase Status of Some Ethiopian State Farm Workers Exposed to Organophosphate Pesticides : Kibruyisfa Lakew, et al. Occupational Safety and Health Division, Region 14 Labour and Social Affairs Bureau—The effects of organophosphate (OP) pesticide exposure on cholinesterase (ChE) activities were assessed in relation to occupational factors by studying 430 pest control workers from three state farms and 161 comparable controls. Plasma cholinesterase (PChE) and erythrocyte cholinesterase (AChE) activities were determined by an electrometric method. Plasma alkaline phosphatase (AP) and glutamic pyruvic transaminase (GPT) were estimated colorimetrically by using diagnostic kits 6391 and 1442520 respectively. Information on OP poisoning symptoms and related occupational factors were collected based on the WHO recommendations. Pest control workers had significantly lower PChE and AChE activities than the controls (P&lt;0.001). In addition, 58 (13.5%) and 47 (10.9%) of the exposed workers had PChE and AChE activities below the lower limits of the controls respectively. Normal plasma AP and GPT values without significant difference from the controls were noted. Among the exposed population, the “spray men” and those who were exposed for 5 years or less were found to be the most affected groups. Although poisoning symptoms were more frequent in the exposed workers than in the controls, only sweating was found to have an association with a significant reduction in AChE activities (P&lt;0.05). The study revealed that the health risks are more apparent in the exposed workers and are of immediate concern. Pre‐placement and periodic medical examination and creation of swareness among the exposed population are recommended to minimize the problem.

Changes in thyroid hormone metabolism in exertional heat stroke with or without acute renal failure.

The effects of exertional heat stroke (ExHS), with or without acute renal failure (ARF), on thyroid hormone metabolism were investigated. Eighteen ExHS patients were recruited and divided into two groups based on the presence or absence of ARF. Eleven age-matched healthy subjects served as a control group. Serum values of T3, T4, TSH, free T4 (FT4), rT3, and sulfated T3 (T3S) were measured in these groups during the acute and recovery stages of ExHS. Serum T3, T4, and FT4 levels were reduced, with reciprocal increases in rT3 and T3S levels as the severity of ExHS increased. The following mean levels of thyroid hormones were found (controls vs. ExHS without ARF vs. with ARF): T3, 1514 vs. 1164 vs. 393 pmol/L (P < 0.05 each); T4, 97 vs. 79 vs. 49 nmol/L (P = NS and P < 0.05, respectively); FT4, 20.5 vs. 19.5 vs. 19.0 pmol/L (P = NS each); rT3, 371 vs. 617 vs. 805 pmol/L (P < 0.05 and P = NS, respectively); and T3S, 30.1 vs. 34.2 vs. 71.1 pmol/L (P = NS and P < 0.05, respectively). The serum TSH levels were not significantly different among the three groups. Significantly negative correlations were found between serum creatinine and T3 (r = -0.75; P < 0.001) and T4 levels (r = -0.65; P < 0.001), whereas no relationship was noted between serum creatinine and rT3 values (r = 0.11; P < 0.05). In contrast, a correlation was observed between serum glutamic pyruvic transaminase and rT3 (r = 0.45; P < 0.01). Thyroid function tests returned to normal after patients recovered. In conclusion, our results show that patients suffering from ExHS, with or without ARF, displayed altered serum thyroid function in proportion to the severity of their condition. No significant changes in serum levels of rT3 were observed between the two groups, whereas a positive relationship was observed between serum rT3 and serum glutamic pyruvic transaminase values, suggesting that the changes in serum rT3 levels were more dependent on extrarenal illness than on renal disease per se. The moderate increase in serum T3S levels found in patients suffering from both ExHS and ARF may represent a decrease in tissue 5'-monodeiodinase activity as found in other nonthyroidal illnesses. A return of serum thyroid function tests to normal values after recovery from ExHS suggests that the low T3 state may play a protective role to prevent undesirable catabolic effects. Replacement therapy is thus not recommended.

P-Chlorophenyl Methyl Sulfide, p-Chlorophenyl Methyl Sulfoxide, and p-Chlorophenyl Methyl Sulfone. II. Subchronic Effects in Rodents and Rhesus Monkeys

Rats, mice, and rhesus monkeys were subjected in subchronic exposures to the chemicals p-chlorophenyl methyl sulfide, p-chlorophenyl methyl sulfoxide, and p-chlorophenyl sulfone. Ninety-one-day toxicity studies were conducted by administering test chemicals to rodents at dietary concentrations of 750, 1500, and 3000 ppm. Clinical signs observed included transient central nervous system (CNS) depression, anorexia, and depressed weight gains. Minor alterations of hematologic and clinical chemistry parameters were also present. Gross and microscopic tissue findings in mice and rats included enlargement, necrotic and megalocytic changes of the liver. Damage to bronchiolar epithelium was observed in mice only at the highest exposure level. A 14-day gavage study in monkeys used daily dosages ranging from 2.5 to 80 mg/kg with an additional 15 days allotted for a recovery phase in one-half the test animals. Compound-related findings included lethality, CNS depression, and emesis. There were no significant compound-induced alterations in electrocardiographic or ophthalmic parameters. Serum blood urea nitrogen and serum glutamic pyruvic transaminase values were elevated in the highest dosage groups for the three test materials concomitant with increases in liver and kidney weights. Microscopic lesions included proliferative changes in lymph nodes, spleen, and bone marrow; hepatocellular vacuolization, degeneration, and necrosis; thyroid follicular cell hyperplasia; and degenerative lesions in gastric and intestinal epithelium. No-observable-effect levels (NOELs) were not established for any of the three test chemicals in the species tested.

Three different patterns of hepatitis C virus infection in chimpanzees.

The relationship between hepatitis C virus RNA and hepatitis C virus-associated antibodies (antibody against the putative capsid protein and C-100 antibody) was determined by nested polymerase chain reaction and enzyme-linked immunosorbent assay in serial serum samples obtained from eight chimpanzees experimentally infected with hepatitis C virus. Three different patterns emerged from the polymerase chain reaction data: the first (group 1) was acute resolving hepatitis with transient appearance of HCV RNA (two cases). The second (group 2) had chronic hepatitis with persistent hepatitis C virus RNA positivity (four cases) and the third (group 3) had chronic hepatitis with intermittent appearance of hepatitis C virus RNA (two cases). In four of eight animals, hepatitis C virus RNA was first detectable in serum 1 wk after inoculation. Although serum HCV RNA was detected in all infected chimpanzees, two were positive only for antibody against the putative capsid protein, whereas two were positive only for antibody to C-100 antigen. In four of eight cases, antibody against the putative capsid protein appeared earlier than did antibody to C-100 antigen, was detected just before or coincident with rising glutamate pyruvate transaminase values and remained positive for a long time even after recovery. Six of eight animals (75%) were still hepatitis C virus RNA positive 1 yr after inoculation, suggesting that the risk of development of the chronic carrier state is high in hepatitis C virus infection. Furthermore, there did not appear to be a good correlation between antibody titer in serum and hepatitis C virus infectivity titer.

The effects of dopamine infusion during operation on the postoperative liver dysfunction.

Dopamine improves renal function and renal blood flow by increasing cardiac output but its effect to ameriolate postoperative liver dysfunction has not yet been defined. Effect of 3-5 microg.kg(-1).min(-1) dopamine was studied in 22 patients who had total gastrectomy (dopamine group), and was compared with 22 patients who underwent the same operation and without dopamine infusion (control group). Liver function was evaluated from serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT) values. Although postoperative SGOT and SGPT values in both groups were increased significantly higher than the preoperative values, the increases in SGOT (40 +/- 14 IU) and SGPT (32 +/- 15 IU) values in the dopamine group were significantly less than those in the control group (67 +/- 27 IU, 43 +/- 19 IU) ( P < 0.05, P < 0.01).In conclusion, these results suggested that this observation might be explained by amelioration of the postoperative liver dysfunction by infusion of dopamine. Dopamine infusion at a small dose during upper abdominal surgery is beneficial for liver function.

Incidence of anti-hepatitis C virus antibodies in non-A, non-B post-transfusion hepatitis in an area of northern Italy.

A total of 210 patients consecutively submitted to heart surgery at the Parma University Hospital and transfused with 1,898 units of blood were followed after transfusion in order to evaluate both the incidence of anti-hepatitis C virus (HCV) seroconversion in non-A, non-B post-transfusion hepatitis (PTH-NANB) cases and the usefulness of the screening for anti-HCV in comparison with that for serum glutamic pyruvic transaminase (SGPT) values in preventing PTH-NANB transmission. Fifteen recipients developed PTH-NANB (group A); ten of them (66.6%) showed anti-HCV seroconversion within 3-12 months. Eight of the ten anti-HCV positive patients developed chronic hepatitis, but none of the five PTH-NANB anti-HCV negative did. None of the 15 controls (group B) randomly chosen among the patient population showed anti-HCV seroconversion. A close correlation with the transmission of PTH was showed by anti-HCV positivity but not by SGPT elevation in blood donors. Eleven of 172 blood products transfused to group A but none of 139 products transfused to group B were anti-HCV positive. The incidence of elevated SGPT values was similar between the two groups of the transfused blood products. Nevertheless, the correlation observed between anti-HCV positivity and SGPT levels in the blood products involved in PTH confirms the need to exclude blood donors with abnormal SGPT values. On the whole, anti-HCV screening of donors showed a predictive value higher than that of SGPT (100% vs. 53.3%), allowing a minor blood donation exclusion.(ABSTRACT TRUNCATED AT 250 WORDS)

Growth of Tyzzer's Organisms in Preneoplastic Hepatocytes of Rats.

Tyzzer's disease in rats carrying preneoplastic or neoplastic lesions in the liver was studied histopathologically and immunohistochemically. The formation of necrotic foci and the growth of organisms were detected within both glutathione S-transferase placental type (GST-P) positive preneoplastic or neoplastic hepatocyte areas and GST-P negative areas. However, plasma glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) values and number of necrotic foci of infected animals having preneoplastic lesions in the liver were smaller than those of infected animals receiving no carcinogenic procedure. These results suggest that the environment consisted of preneoplastic hepatocytes was unsuitable for the growth of organisms as compared with that of intact hepatocytes though the organism could grow within the preneoplastic hepatocytes.

Provocation of massive hepatic necrosis by endotoxin after partial hepatectomy in rats

When rats received endotoxin 48 hours after two-thirds liver resection, 50% of them died within 12 hours with massive hepatic necrosis at a dose that did not affect sham-operated rats. In the hepatic sinusoids, fibrin deposition and endothelial cell destruction occurred 5 hours after endotoxin administration. When antithrombin III concentrate was infused concomitantly with endotoxin administration, all rats survived 12 hours, and the extent of hepatic necrosis and the deranged serum glutamic pyruvic transaminase values were significantly attenuated at 5 hours compared with those in the control rats. Similar improvements in the incidence of mortality and liver injury were observed after treatment with gum arabic before hepatectomy. The stimulatory state of Kupffer cells based on the ability to produce Superoxide anions estimated by formazan deposition after liver perfusion with nitro blue tetrazolium and phorbol myristate acetate was increased between 24 and 72 hours after operation. This increase disappeared after gum arabic treatment. It is concluded that massive hepatic necrosis can occur as a result of sinusoidal fibrin deposition provoked by endotoxin in partially hepatectomized rats. Activated Kupffer cells may contribute to this provocation.

Short-Term Changes of Laboratory Values after Extracorporeal Shock Wave Lithotripsy: A Comparative Study

Since the inception of extracorporeal shock wave lithotripsy 9 years ago treatment strategies have changed. Patients currently are receiving larger numbers of higher voltage shock waves. However, upper limits of safety for these treatments have not been established. In an attempt to address this question a comparative study of effects of extracorporeal shock wave lithotripsy on laboratory values between 2 stone centers, Munich and Tucson, using different treatment strategies 3 to 4 years apart was done to identify possible differing effects. Patient stone burdens were similar. However, Tucson patients received almost twice the number of shock waves. Both groups showed a significant decrease in hematocrit (by 8.7 per cent in Munich and 6.4 per cent in Tucson). Both groups had a significant increase in white blood count (14.5 per cent in Munich and 22.7 per cent in Tucson). In addition, both groups had increased serum levels of glutamic oxaloacetic transaminase of 43.3 and 59.7 per cent, respectively. However, only the Tucson group showed increases in serum glutamic pyruvic transaminase, lactic dehydrogenase and total bilirubin in 51.5, 40.8 and 46 per cent of the patients, respectively. Further analysis indicated that extracorporeal shock wave lithotripsy was associated with 2 significant short-term changes of blood or serum laboratory values: 1) those presumed to be dilutional from related infusions, rather than extracorporeal shock wave lithotripsy treatments themselves and 2) those presumed to be related to cellular injury after high energy treatments. Elevated serum glutamic pyruvic transaminase, lactic dehydrogenase and total bilirubin values of Tucson patients clearly were related to higher kilovolts and number of shocks or to treatments on the right side. These observations probably resulted from transient trauma to the liver, as well as renal cells.

Effects of deteriorated frying oil and dietary protein levels on liver microsomal enzymes in rats

AbstractThis study was conducted to investigate the effects of deteriorated used frying oil (DUFO) and dietary protein levels upon the hepatic microsomal drugmetabolizing enzyme system. Fresh soybean oil was subjected to a deep‐frying process at 205±5°C for four six‐hr periods. The resultant DUFO was incorporated into high protein (HU) (27% lactalbumin) or low protein (LU) (8% lactalbumin) test diets at a 15% level. High protein (HF) and low protein (LF) diets containing fresh soybean oil served as the control. Male Long‐Evans young rats fed the test diets for eight weeks showed decreased fat absorption and increased red blood cell (RBC) in vitro hemolysis. The activities of hepatic aminopyrine N‐demethylase (AD), aniline hydroxylase (AH), NADPH‐cytochrome C reductase (NCD), UDP‐glucuronyl transferase (UDPGT) and glutathione S‐transferase (GST) as well as cytochrome P‐450 content were significantly increased in rats fed the HU diet. However, the AD, AH and GST activities, as well as the cytochrome P‐450 content of the LU group, were increased to a lesser extent and significantly lower than those of the HU group. Rats fed the LU diet were the only group that showed significantly elevated serum GOT (E.C. 2.6.1.1, glutamate‐oxaloacetate transaminase) and GPT (E.C. 2.6.1.2, glutamatepyruvate transaminase) values. Supplementation of 0.3% DL‐methionine to the HU diet further increased GST activity. Unexpectedly, rats fed the low protein control diet (LF) also had raised levels of AD, AH and UDPGT activities as well as in vitro RBC hemolysis. It was concluded that rat hepatic microsomal enzymes are induced by dietary DUFO and that the level of induction is influenced by dietary protein level.

Liver Membrane Antibodies in Chronic Delta Hepatitis

The correlation between the presence of liver membrane antibodies (LMA) and delta superinfection in chronic hepatitis B was studied in 136 chronic hepatitis patients, 20 hepatitis B surface antigen asymptomatic carriers and 50 healthy controls, by testing for the presence of LMA, hepatitis B virus markers and anti-delta (anti-HD). Neither anti-HD nor LMA were detected in controls or in asymptomatic carriers. LMA positivity was statistically higher (p less than 0.001) in anti-HD-positive patients than in those with no anti-HD. Gamma globulin and glutamic pyruvic transaminase values were increased both in anti-HD- and LMA-positive patients with respect to those who were negative. In conclusion, a close association between the positivity to anti-HD and the presence of circulating LMA was found.

Comparison of the Requirements for Hepatic Injury with Halothane and Enflurane in Rats

A rat model of enflurane-associated hepatotoxicity was compared with the halothane-hypoxia (HH) model (adult male rats, phenobarbital induction, 1% halothane, 14% O2, for 2 hr). The enflurane-hypoxia heating (EHH) model involved exposing phenobarbital-pretreated male adult rats to 1.5-1.8% enflurane at 10% O2 for 2 hr with external heating to help maintain body temperature. Exposure to either anesthetic without temperature support led to a decrease in body temperature of 7-9 degrees C, while heating the animals during anesthesia resulted in only a 0.5-2 degree decrease. Reducing the oxygen tension to 10% O2 combined with heating the animals during exposure produced significant decreases in the oxidative metabolism of both halothane and enflurane as compared to exposures of 14% O2. The same conditions also caused a significant increase in the reductive metabolism of halothane, indicating that a severe hepatic hypoxia or anoxia occurs during anesthesia at 10% O2 with external heating. The time course of lesion development in the HH model paralleled results obtained with an oral dose of CCl4: gradual progression of necrosis up to 24 hr. EHH resulted in a classic hypoxic/anoxic injury with elevated serum glutamate pyruvate transaminase values and a watery vacuolization of centrilobular hepatocytes immediately after exposure. The HH model required phenobarbital pretreatment of the rats for expression of hepatic injury; EHH did not. Heating of the animals during anesthesia exposure was necessary for enflurane-induced hepatoxicity but had little effect on the HH model. Exposure to 5% O2 without anesthetic mimicked EHH in both requirements for and type of hepatic injury.

Blood cellular and biochemical studies in canine dirofilariasis.

Haematological studies in heartworm-infected dogs revealed low haemoglobin concentration, increased erythrocyte sedimentation rate and a marked increase in lymphocyte percentage. Biochemical analysis of serum of dogs infected with heartworm showed increases in serum total bilirubin, serum globulin, chloride, phosphorus, serum glutamic oxaloacetic transaminase and serum glutamic pyruvic transaminase values and a decrease in albumin content.

Plasma concentrations and electrocardiographic alterations after repetitive administration of propoxyphene to dogs

Propoxyphene hydrochloride was administered orally to four dogs every 8 hr for 19 days. Initial doses of 20 mg/kg were increased to 60 mg/kg in 5 to 15 mg/kg increments every 3 to 4 days. At the conclusion of the experiments animals were ambulatory although signs of toxicity including anorexia, sedation, tremors, and emesis were noted periodically throughout the study. Slight elevations in alkaline phosphatase and serum glutamate pyruvate transaminase values were also observed. Plasma concentrations of propoxyphene (P) (2.3±0.5 μg/ml) and norpropoxyphene (NP) (18.4±4.7 μg/ml), its major metabolite, were markedly elevated over those observed with a single near-lethal dose administered to naive dogs (P, 0.83 μg/ml; NP, 2.56 μg/ml). Tissue concentrations of P and NP were in excess of plasma concentrations showing marked tissue accumulation of both compounds. Electrocardiograms (ECG) showed an increase in PR interval after the first dose of propoxyphene. Doses from 20 to 45 mg/kg produced no further lengthening of the PR interval. Only when dogs were receiving 60 mg/kg (three times daily) were further changes in this interval observed, along with alterations in the QRS complex and T wave portions of the ECG. The average heart rate of these dogs was not significantly altered during the course of the study. At necropsy, mild superficial focal erosions in the mucosa of the stomach and upper small intestine were noted. No other histological changes were observed. These results demonstrated that in the dog, high plasma and tissue concentrations of P and NP can occur without causing significant toxic or lethal effects.