Evaluation of enzymatic and non-enzymatic antioxidants in seminal plasma of men with genitourinary infections, varicocele and idiopathic infertility.

UNLABELLED: This study was aimed to assess the antioxidant enzymatic and non-enzymatic compounds in semen of infertile men. Seventy-four infertile patients were grouped according to their clinical diagnosis: genitourinary infection, varicocele, idiopathic infertility. Semen samples of fertile men represent the control. Semen characteristics were evaluated by light and transmission electron microscopy (TEM). TEM data was quantified with a mathematical formula, which provides numerical scores. Spectrophotometric and HPLC methods were used to measure the amount of reduced (GSH), oxidised glutathione (GSSG), ascorbic acid (AA) and malondialdehyde (MDA, marker of lipid peroxidation) and the activity of glutathione reductase, catalase (CAT), glutathione peroxidase. Infertile groups showed significantly decreased values of sperm parameters vs. CONTROLS: In infection and varicocele groups, the seminal MDA levels were significantly increased when compared to controls (p < 0.001), indicating an alteration of oxidative status and a peroxidative damage. In infection and varicocele groups, AA levels were reduced (p < 0.05) vs. control; in the varicocele group, the GSH levels were also decreased (p < 0.05). Significantly higher CAT activity was observed in infection and varicocele groups vs. fertile men (p < 0.001 and p < 0.05 respectively). The GSH/GSSG ratio was significantly decreased in varicocele and idiopathic infertility groups vs. control (p < 0.01). The study of the alteration of a single parameter of oxidative stress or of the antioxidant system may not have a relevant clinical value to estimate male fertilising potential and the background of infertility causes, since complex and multifactorial mechanisms are involved in different pathologies. In our study, each pathology is characterised by a definite pattern of markers such as MDA and enzymatic and non-enzymatic antioxidant compounds. In the different pathologies related to infertility, the identification of the complex of involved parameters could be useful in the diagnosis, prognosis and in the choice of a possible treatment such as specific antioxidant supplements.

Semen characteristics and malondialdehyde levels in men with different reproductive problems.

The aim of this study was to assess the level of malondialdehyde (MDA) in the seminal plasma of infertile men and to highlight a relationship between the level of MDA and semen parameters. Eighty-one infertile patients were divided into groups according to their clinical diagnosis: genitourinary infections, varicocele and idiopathic infertility. Semen quality was assessed by light and transmission electron microscopy (TEM). TEM data were quantified with a mathematical formula able to obtain a fertility index and the percentage of sperm apoptosis, immaturity, and necrosis. Seminal MDA levels were determined by spectrofluorometry. Scrotal Eco-color Doppler was used to detect the varicocele. Infected patients had a positive bacteriological semen analysis. A control group consisted of 14 normospermic fertile men. Fertile group showed significantly increased values of sperm concentration, motility, and fertility index compared to infertile groups. In the infertile groups, sperm motility, concentration, apoptosis, and fertility index were not significantly different. In infection group, the percentage of necrosis was significantly higher than that observed in fertile men, varicocele, and idiopathic infertility groups (p < 0.001). MDA levels increased significantly in infection group in comparison with varicocele group (p < 0.01), idiopathic infertility group, and fertile men (p < 0.001) and in varicocele group compared to idiopathic infertility group (p < 0.001). In infection group, MDA levels positively correlated with sperm concentration (p < 0.01), fertility index (p < 0.05), and necrosis (p < 0.001), whereas a negative correlation was found with motility (p < 0.01). In varicocele group MDA levels correlated positively with necrosis and negatively with immaturity (p < 0.05). In fertile men and idiopathic infertility group, they did not show any correlation. In conclusion, we suggest that the evaluation of seminal MDA may be a good marker for understanding pathologies responsible of a sperm motility reduction such as urogenital infections or inflammatory status.

Role of oxidative stress in cocaine-induced cardiotoxicity and cocaine-related death.

Cocaine-induced cardiovascular disorders such as hypertension, thrombosis, myocardial dysfunction, cardiac dysrhythmias and endocarditis have received widespread attention in the context of cocaine abuse. The number of sudden deaths from cardiac causes, including myocardial infarction, ventricular tachyarrhythmia or aortic dissection, is also increasing. This manuscript will highlight the recent employment of study about cocaine cardiotoxicity and oxidative stress. Evidence has revealed that cardiac oxidative stress is a prominent early event of cocaine administration, which severely compromises the cardiac antioxidant cellular system and causes cardiac antioxidant cellular system injuries. Oxidative damage such as peroxidation of membrane phospholipids and depletion of nonenzymatic antioxidants such as glutathione have been found in the myocardium of chronic cocaine-treated animals and in patients. The data indicate that cocaine administration compromised the heart's antioxidant defense system. About the mechanisms involved in the cellular damage, the evidence that cocaine causes apoptosis in the heart comes from in vivo study. In animals model after short-term and long term-cocaine administration, the investigators demonstrates the role of Reactive Oxygen Species as a trigger of cardiac injury induced by cocaine. Cocaine also increased infiltration of inflammatory cells in the heart, and apoptotic cells were predominantly found near inflammatory cells. The role of oxidative stress in cocaine-induced apoptosis in the heart is wide studied and documented.

Acute administration of 3,4-methylenedioxymethamphetamine (MDMA) induces oxidative stress, lipoperoxidation and TNFα-mediated apoptosis in rat liver.

Liver toxicity is one of the consequences of ecstasy (3,4-methylenedioxymethamphetamine MDMA) abuse and hepatocellular damage is reported after MDMA consumption. Various factors probably play a role in ecstasy-induced hepatotoxicity, namely its metabolism, the increased efflux of neurotransmitters, the oxidation of biogenic amines, and hyperthermia. MDMA undergoes extensive hepatic metabolism that involves the production of reactive metabolites which form adducts with intracellular nucleophilic sites. MDMA-induced-TNF-α can promote multiple mechanisms to initiate apoptosis in hepatocytes, activation of pro-apoptotic (BID, SMAC/DIABLO) and inhibition of anti-apoptotic (NF-κB, Bcl-2) proteins. The aim of the present study was to obtain evidence for the oxidative stress mechanism and apoptosis involved in ecstasy-induced hepatotoxicity in rat liver after a single 20 mg/kg, i.p. MDMA administration. Reduced and oxidized glutathione (GSH and GSSG), ascorbic acid (AA), superoxide dismutase (SOD), glutathione peroxidase (GPx), glutathione reductase (GR) and malondialdehyde (MDA), an indicator of lipid peroxidation, were determined in rat liver after 3 and 6h after MDMA treatment. The effect of a single MDMA treatment included decrease of GR and GPx activities (29% and 25%, respectively) and GSH/GSSG ratio (32%) with an increase of MDA (119%) after 3h from ecstasy administration compared to control rats. Liver cytosolic level of AA was increased (32%) after 6 h MDMA treatment. Our results demonstrate a strong positive reaction for TNFα (p<0.001) in hepatocytes and a diffuse apoptotic process in the liver specimens (p<0.001). There was correlation between immunohistochemical results and Western blotting which were quantitatively measured by densitometry, confirming the strong positivity for TNF-α (p<0.001) and NF-κB (p<0.001); weak and intense positivity reactions was confirmed for Bcl-2, SMAC/DIABLO (p<0.001) and BID reactions (p<0.001). The results obtained in the present study suggest that MDMA induces loss of GSH homeostasis, decreases antioxidant enzyme activities, and lipoperoxidation that causes an oxidative stress that accompaines the MDMA-induced apoptosis in liver cells.

A novel metronomic chemotherapy regimen of weekly platinum and daily oral etoposide in high-risk non-small cell lung cancer patients.

The aim of this pilot phase II trial was to investigate the toxicity and anti-tumour activity of a novel metronomic regimen of weekly cisplatin (CDDP) and oral etoposide (VP16) in high-risk patients with advanced NSCLC. The study enrolled 31 high-risk patients (27 men and 4 women aged 16-82 years; mean, 64.3) with NSCLC (18 stage IIIB and 13 stage IV) and an ECOG performance status of < or = 3, all of whom received weekly CDDP 30 mg/m2 iv on days 1, 8, 14 and 28 of each cycle and oral daily etoposide 50 mg/m2 on 21 of the 28 days. The most frequent adverse events were grade III leukopenia and anemia; nevertheless, three patients died of pulmonary embolism after 2, 3 and 6 weeks of treatment. The objective response (OR) rate was 45.2% (2 complete and 12 partial), and the disease control rate was 58.1% (14 ORs and 4 disease stabilisations). The mean time to progression and survival were respectively nine months (95% CI, 6.3-15.8 months) and thirteen months (95% CI, 9.1-20.5 months). Pharmacological analysis showed that this metronomic regimen allows a much greater median monthly area under the curve of CDDP and VP16 than conventional treatment schedules. Our findings also suggest that this treatment schedule may affect tumour growth and neoangiogenesis by changing peripheral blood vascular-endothelial growth factor levels. These preliminary results indicate that our metronomic regimen is well tolerated and active, even in patients with a very poor prognosis.

Blood profiles, body fat and mood state in healthy subjects on different diets supplemented with Omega-3 polyunsaturated fatty acids.

BACKGROUND: Diets and Omega-3 polyunsaturated fatty acids have been considered as important factors to reduce the risk of cardiovascular and inflammatory diseases, but there are few details on the effects on healthy subjects. The aim of the present study was to examine the variation of several physiological parameters in healthy subjects on different diets supplemented with Omega-3 fatty acids. MATERIALS AND METHODS: The experiment was carried out on 33 subjects divided into four groups according to a double-blind cross-over design with a 1 : 1 ratio for Omega-3 (vs. placebo) and open-label parallel-groups with a 1 : 1 ratio for the Zone diet (vs. the diet suggested by the Italian National Research Institute for Nutrition and Foods). Blood samples were collected at the beginning of the experiment and after 35 (cross-over) and 70 days. The Profile of Mood States test (POMS) was also performed. RESULTS: The arachidonic acid/eicosapentaenoic acid ratio (AA/EPA) was strongly reduced by Omega-3 with a supplementary effect of the diet and in particular the Zone diet. The AA/EPA reduction was correlated with a concomitant decrease of insulin and homocysteine levels. The Zone diet reduced skinfold thickness and body fat percentage and also showed antioxidant effects. The mood state changed after Omega-3 supplementation, with an increased POMS index. This was related to a concomitant reduction of AA/EPA and was particularly evident in the Zone diet. CONCLUSION: AA/EPA and mood state are differently influenced by diet and Omega-3, body fat is particularly reduced by Zone diet, while blood parameters such as triglycerides/HDL ratio, insulin and homocysteine are related to AA/EPA variations. These findings are discussed in terms of differences in the composition of the diets and the influences of Omega-3 on physiological functions.

Is a long-term ranitidine-based triple therapy against Helicobacter pylori only a heritage of the past? A prospective, randomized clinicopharmacological study.

BACKGROUND: Acid suppression plus two antibiotics is currently considered the gold standard anti-Helicobacter pylori treatment, but the effective role of gastric antisecretory drugs is still poorly understood. AIMS: To compare a 14-day ranitidine-based triple regimen against Helicobacter pylori with one based on omeprazole, and to study the influence of antisecretory drugs on metronidazole pharmacokinetics in human plasma. METHODS: A total of 150 dyspeptic H. pylori-infected patients were randomized for ranitidine 300 mg b.d. (RCM group) or omeprazole 20 mg b.d. (OCM group) 14-day triple therapy, with clarithromycin 500 mg b.d. and metronidazole 500 mg b.d. On the eighth day of therapy, metronidazole pharmacokinetics was studied in plasma by high-performance liquid chromatography. The pharmacokinetic parameters (terminal half-life, area under the curve, peak-plasma level, peak time) of metronidazole were computed using standard non-compartmental methods. H. pylori status was monitored before and 4 weeks after the end of therapy by histology, serology and rapid urease test. RESULTS: On an intention-to-treat basis, eradication rates were 91 and 76% for the RCM and OCM groups respectively (P < 0.02). Significantly different pharmacokinetic parameters of metronidazole were found between the groups: peak-plasma level (P < 0.01) and area under the curve (P < 0.02). CONCLUSION: Our results show that the RCM regimen was more effective than that based on OCM and that the antisecretory drugs affected metronidazole availability, increasing the efficacy of ranitidine-based regimens.

Pharmacokinetics of mitomycin C after resection of peritoneal carcinomatosis and intraperitoneal chemohyperthermic perfusion.

Over the last few years surgery on patients with abdominal malignancies has become more aggressive but the majority of patients present locoregional recurrence as peritoneal dissemination. Cytoreductive surgery followed by intraperitoneal chemohyperthermic perfusion (ICHP) has been described for treatment and prevention of locoregional cancer spread from various origins. This paper reports our study of the pharmacokinetics of mitomycin C (MMC) administered by intraperitoneal chemohyperthermic perfusion (ICHP) in patients with peritoneal carcinomatosis. 28 patients received MMC 20 mg/m2 intraperitoneally as a perfusion over 60 min. MMC was determined in perfusate, plasma and urine samples with a UV-HPLC method. A compartmental model was used to fit the drug concentrations in plasma and perfusate. Our results showed a mean maximum plasma concentration (Cmax) of 0.14 +/- 0.086 microg/ml with a peak time (Tmax) of 48..7 +/- 5.61 min. The mean area under the curve (AUC) and terminal half-life (t1/2) were 15.8 +/- 9.8 mg x min/L and 83.7 +/- 31.74 min respectively. Clearance (CL) was estimated by fitting the data by a compartmental model and the mean value was 72 +/- 66 L/h. The percent of the dose absorbed was very variable and ranged between 14 and 57% (mean 37 +/- 14%). The mean percentage of dose recovered unchanged in the urine during 24 hours was 7.21 +/- 3.73%. We conclude that ICHP in patients with peritoneal surface malignancies seems to have clinical value since it gives high peritoneal and tumor MMC concentrations with limited systemic exposure and toxicity.

Gemcitabine (GEM), 5-fluorouracil (5-FU) and folinic acid (FA) in patients with different gastroenteric malignancies.

This phase II clinical trial was performed in order to evaluate the pharmacokinetics, toxicity and anti-tumor activity of a novel combination of gemcitabine (GEM), 5-fluorouracil (5-FU) and folinic acid (FA) designed on a specific translational basis. Every 4 weeks, 44 patients with various gastroenteric malignancies, 29 of whom had pancreas carcinoma, received a short intravenous (i.v.) infusion of FA (100 mg/m2) and 5-FU (400 mg/m2) on days 1-5, and GEM 1000 mg/m2 on days 1, 8 and 16. Our results suggest that, although this treatment leads to hematological and gastroenteric toxicity, it is very active in patients with pancreatic carcinoma. We therefore believe that an improved version would merit further investigation in larger scale trials.

[Physical exercise during hemodialysis session: effect on quality of life]. / Contributo dell'esercizio fisico in corso di emodialisi sulla qualità di vita del paziente emodializzato.

There are many studies showing beneficial psychophysical effects of exercise in dialyzed patients. Moreover, it has been suggested that exercise positively correlates with better metabolism, better blood pressure control and with total hemoglobin. In our dialysis unit eight dialyzed patients (average age = 66.7 years), for eight weeks participated in physical training with bike (Reck Moto Med Letto) during dialysis treatment. Controls of glucose metabolism, blood pressure and dialysis efficiency index (Kt/V and URR) at rest and during exercise was performed. All patients responded well to exercise and expressed better muscular performance during and after exercise time. Our study showed in all patients improvement of Kt/V and URR index after physical exercise period, compared to exercise free time (p < 0.005). We suggest that exercise during dialysis treatment is safe and consents either better psychophysical performance or better dialytic efficiency.

Gemcitabine increases systemic 5-fluorouracil exposure in advanced cancer patients.

A number of recent clinical trials testing the combination of 5-fluorouracil (5-FU) and gemcitabine in patients with advanced pancreatic adenocarcinoma have shown a significant clinical response rate, but also significant toxicity. As the two antimetabolites may interact at several biochemical levels along their pathways of activation, we investigated whether gemcitabine (GEM) affects 5-FU pharmacokinetics in cancer patients. Thus, we compared 5-FU pharmacokinetics in two groups of patients with various cancers who received the same schedule of 5-FU and folinic acid (FUFA), with or without GEM. There was a significant increase in systemic (5-FU) exposure and toxicity in the FUFA plus GEM group. Our finding may be useful in designing future studies of the combination in order to reduce the occurrence of side-effects and to maximise the antitumour activity.

A novel biweekly pancreatic cancer treatment schedule with gemcitabine, 5-fluorouracil and folinic acid.

Pancreatic adenocarcinoma is a common disease considered to be poorly responsive to antiblastic treatment. Recent clinical and preclinical results suggest that a combined treatment of gemcitabine (GEM), 5-flurouracil (5-FU) and folinic acid (FA) offers a clinical benefit in patients with advanced pancreas adenocarcinoma. The aim of this phase II clinical trial was to evaluate the antitumour activity and toxicity of a novel biweekly schedule of this combination in patients with pancreatic adenocarcinoma. A total of 42 patients received a 30 min infusion of FA (100 mg m(-2)) and 5-FU (400 mg m(-2)) (FUFA) on days 1-3, and GEM 1000 mg m(-2) on day 1 every 15 days. We observed 13 objective responses (two complete, 11 partial) and 23 stable diseases. The median time to progression was 9.75 months (95% Confidence Interval (CI), 6.88-12.62) and the median overall survival was 13.10 months (95% CI 9.64-16.56). There were seven cases of each grade III gastroenteric and haematological toxicity. The GEM plus FUFA combination appears to be well tolerated and very active in patients with pancreatic carcinoma.

[Renal atheroembolic disease: evaluation of the efficacy of corticosteroid therapy]. / Malattia ateroembolica: valutazione dell'efficacia della terapia steroidea.

BACKGROUND: Even though many organs may be involved and clinical manifestations are extremely variable, a sudden worsening of renal function after vascular surgery or invasive angiographic manoeuvres is a clue for the diagnosis of renal cholesterol crystal embolization. In rare cases the disease may also occur spontaneously during anticoagulant or thrombolytic therapy. Renal atheroembolism is becoming increasingly recognized as an important cause of renal failure particularly in elderly men, and is often associated with a bad outcome. To date there is no specific and proven useful treatment apart from a few anecdotal reports on the benefits of corticosteroids. PATIENTS AND METHODS: We report a group of seven patients with cholesterol atheroembolic disease presenting acute renal failure; in six patients the disease appeared after coronary arteriography and PTCA performed in the last four months, and in one patient in an apparently spontaneous form. All the patients presented cutaneous lesions, livedo reticularis, purpuric rush, necrosis of the toes; laboratory data showed an increase of acute phase proteins and eosinophilia. Results. Treatment with prednisolone was begun at a dose of 40 mg/day i.v. for four days; the dose was reduced to prednisone 0.4-0.5 mg/kg/day for 1 week, than gradually reduced further and stopped within a month. Following therapy renal function rapidly improved; clinical symptoms of malaise and abdominal discomfort subsided, with amelioration of skin lesions and cyanosis of toes. CONCLUSIONS: Despite the small number of patients studied, our experience suggests that corticosteroid treatment is an effective therapeutic option in cholesterol renal atheroembolic disease, especially in the more severe cases of acute renal failure.

Markers of cardiac oxidative stress and altered morphology after intraperitoneal cocaine injection in a rat model.

This study was designed to assess the parameters of myocardial oxidative stress and related cardiac morphological changes following intraperitoneal cocaine exposure in rats. The cardiac levels of reduced glutathione(GSH), oxidised glutathione(GSSG), ascorbic acid (AA), and the production of malondialdehyde (MDA) were measured, as well as the variations of activity in the enzyme systems involved in cell antioxidant defence, glutathione peroxidase (GSH-Px), glutathione reductase (GR) and superoxide dismutase (SOD). After chronic cocaine administration for 30 days GSH was significantly depleted in the heart from 30 min (P < 0.001) to 24 h (P < 0.001) after exposure, and GSSG was increased for a similar time (P < 0.05 at 30 min and P < 0.01 at 24 h). SOD increased during the first hour (P < 0.001), GR and GSH-Px both increased from 30 min to 24 h, and these increases were statistically significant (P < 0.01 and P < 0.001 at 30 min and P < 0.01 and P < 0.001 at 24 h, respectively). The AA levels increased after 1 h (P < 0.01), remaining significantly so for 24 h (P < 0.001) and MDA increased from 30 min to 24 h, all values being highly significant (P < 0.001). The body weight was significantly (P < 0.001) reduced in both cocaine groups (40 mg/kg x 30 days and 40 mg/kg x 10 days + 60 mg/kg x 20 days). The heart weight (P < 0.01) and its percentage of the body weight (P < 0.001) were significantly higher in these two groups than in the controls. Similarly, in the noradrenaline 4 mg/ kg x 30 days group, the body weight was significantly (P < 0.001) reduced and the heart weight (P < 0.01) and its percentage of body weight (P < 0.001) were significantly higher than in the controls. In comparing the cocaine and noradrenaline experiments, the frequency and extent of cardiac lesions obtained with 40 mg/kg x 10 days + 60 mg/kg x 20 days of cocaine were similar to those with 8 mg/kg of noradrenaline at 24 h. In this experimental model, cocaine administration compromised the antioxidant defence system of the heart associated with a significant increase of heart weight and the percentage of body weight.

Myocardial findings in fatal carbon monoxide poisoning: a human and experimental morphometric study.

The aim of this study was to define the status of the myocardium in selected human cases of acute, fatal carbon monoxide intoxication and the myocardial changes in rats exposed to carbon monoxide in relation to the type of cardiac arrest and the effects of reoxygenation following pre-fatal CO intoxication. The human study consisted of 26 cases (17 accidental and 9 suicide) of acute, fatal CO intoxication, without evidence of obstructive coronary atherosclerosis or history of ischemic heart disease which were compared with 45 cases of fatal head trauma in subjects who died instantaneously (26 cases) or within 1-12 h (19 cases). Inhalation of a lethal dose of CO in rats was compared with sub-lethal doses plus reoxygenation with and without pre-treatment by a betablocker. In all human and experimental histological sections, changes were normalised per mm2 area. In the human cases the myocardium did not show any ischemic types of changes or other lesions. Only in "three accidental" cases a few, small foci of coagulative myocytolysis were detected. In the case of spontaneous death in 31 rats following CO intoxication, no pathological myocardial changes were seen. Of the 15 "reoxygenated" rats, 2 of the 7 spontaneous deaths presented coagulative myocytolysis with 15 +/- 6 foci and 381 +/- 255 necrotic myocells. All the eight rats sacrificed at 3 h had coagulative myocytolysis with 5 +/- 4 foci and 60 +/- 47 myocells. Of the 24 reoxygenated rats pre-treated with a betablocker, 5 died spontaneously after a short survival and 2 of these showed 11 +/- 9 foci and 21 +/- 20 myocells. The 19 rats sacrificed after 3 h all presented coagulative myocytolysis with figures of 75 +/- 43 and 356 +/- 301 with 0.5 mg/kg of propranolol hydrochloride and 55 +/- 45 and 253 +/- 216 with 2 mg/kg, respectively.

Amiloride pharmacokinetics in rat.

The kinetics of amiloride was investigated in plasma, urine, faeces and tissues of rats after oral (10 mg/kg) and i.v. (10 mg/kg bolus and 35 microg/h for 4-days infusion) administration. Initially the experimental data were analyzed by a multiexponential model, then a compartmental model was developed to describe the drug kinetics in plasma, urine, faeces and tissues after the i.v. bolus and the oral administration simultaneously. Aim of the model was also to predict the drug kinetics in plasma and tissues of rats after continuous i.v. infusion. The results of the prediction and the discrepancies between prediction and observed data allowed a deeper insight into the pharmacokinetics of amiloride.

High-performance liquid chromatography of flufenamic acid in rat plasma.

A simple high-performance liquid chromatographic (HPLC) method for the determination of flufenamic acid in rat plasma is described. After liquid-liquid extraction, the drug is separated by HPLC on a 5-microns octadecylsilica column (Nucleosil C18) with ultraviolet detection at 280 nm. Linear calibration graphs for flufenamic acid were constructed from 0.5 to 15 micrograms/ml. The method has been applied to a pharmacokinetic study in animals.

Effect of acetaminophen on glutathione levels in rat testis and lung.

Glutathione (GSH) levels in rat testis and lung after oral administration (3 g/kg) of acetaminophen (APAP) were studied. At the administered dose APAP is present in each organ and influences the GSH levels. APAP value of 114 micrograms/g was obtained in testis at 6 hr (peak time); in the lung the Cmax was 92 mu/g at 8 hr and this value lasted several hours longer than that in testis. GSH levels are also affected differently in the organs studied after APAP administration; the lungs seem to be the primary organ undergoing the depleting action of APAP. This process could not only cause toxicity, but also predispose those organs to the action of toxic compounds responsible for specific pathologies.

Rapid and sensitive determination of piroxicam in rat plasma, muscle and skin by high-performance liquid chromatography.

A rapid and precise high-performance liquid chromatographic method for the determination of piroxicam in a variety of biological samples has been developed. A reversed-phase column, isocratic elution and ultraviolet detection were employed. Calibration curves were reproducible and highly linear, with correlation coefficients typically averaging over 0.992. The detection limit of the assay was 100 ng/ml for all biological samples examined (at a signal-to-noise ratio of 3:1). Validation of the method demonstrated a good sensitivity, accuracy and precision. The method has been adopted for a pharmacokinetic study in rats.