Hugo Juárez Olguín

Assessment of Oxidative Damage Induced by Acute Doses of Morphine Sulfate in Postnatal and Adult Rat Brain

The aim of the present study is to evaluate the oxidative damage in rats of different ages. Weaned rats of 25xa0g and adults of 300xa0g were used in groups of 6, a single i.p. dose of morphine sulfate of 3, 6 or 12xa0mg/kg was administered. All animals were sacrificed to measure GSH and 5-HT levels in brain by liquid chromatography, as well as Na+, K+-ATPase and total ATPase enzymatic activity. 5-HT levels decreased significantly (p<0.05) in adult animals that received 3 and 6xa0mg morphine. Na+, K+-ATPase activity increased significantly (p<0.05) in all groups of weaned animals. In adult animals, Na+, K+-ATPase and total ATPase partially diminished. GSH levels diminished significantly (p<0.05) both in weaned and in adult groups. The results indicate age-induced changes in cellular regulation and biochemical responses to oxidative stress induced by morphine.

Experimental hemolysis model to study bilirubin encephalopathy in rat brain

None of experimental models used to study the toxic effect of unconjugated bilirubin brain accumulation, reproduce the conditions in which the hyperbilirubinemia is a consequence of a hemolytic process, i.e. when important amounts of bilirubin and iron are released. The aim was to develop an animal model to determine the role of bilirubin and iron, in the encephalopathy secondary to a hemolytic disease. Male Wistar rats 7 days old (n=30) were treated with phenylhydrazine as hemolytic at 75 mg/kg body weight intraperitoneally for 2 days and euthanized 24 h after the last dose. Hemoglobin, hematocrit, serum and brain bilirubin, serum iron and lipoperoxidation products, as well as neuronal damage and iron positive staining were evaluated and compared among treated and untreated (n=10) animals. The animals with induced hemolysis showed significant reduction in hemoglobin and hematocrit, increased concentration of total and conjugated bilirubin, as well as of serum iron and lipid peroxidation products. The neuronal damage in treated animals included the presence of altered neurons spread out among normal cells, as well as of iron-staining positive cells. With the use of appropriated pharmacological procedures, the characteristics of the model can be useful to dissect the participation of both bilirubin and iron, on the bilirubin encephalopathy secondary to hemolysis.

Effect of testosterone and steroids homologues on indolamines and lipid peroxidation in rat brain

The purpose of the present study was to evaluate the effect of 4-pregnen-17-hydroxy-3-one (A) and two steroids homologues: 3beta-acetoxy-5,16-pregnadien-20-one (B) and 3beta-acetoxy-16alpha-17alpha-epoxy-4-pregnen-20-one (C). Male Wistar rats were treated with o-cresol combined (A, B or C) steroids. Lipid peroxidation status as result of measurement reactive substances to thiobarbituric acid (TBARS) as well as serotonin (5-HT) and its precursor 5-hydroxytryptophan (5-HTP) were measured. The prostate glands were weighed, the 5alpha-reductase activity was determined. The animals treated with A, B, and C steroids showed a slight increase in both 5alpha-reductase activity and prostate size. 5-HT and 5-HTP levels did not change significantly, and TBARS showed an increase in the group treated with B steroid and a decrease in the A steroid group with significant differences in both groups (p<0.05) versus control group. Results suggest that A steroid reduces TBARS in rat brain, perhaps as a result of the interaction between the testosterone unsaturated carbons and OH(-) groups with free radicals.

Reliable method for the determination of ranitidine by liquid chromatography using a microvolume of plasma.

Abstract The aim of the present study was to develop a simple method to measure ranitidine, using 100 μl of plasma, by high-performance liquid chromatography with a Symmetry C 18 column and UV detection at 313 nm. Linearity was assessed in the range from 50 to 1500 ng ml −1 and had a correlation coefficient of 0.999. The inter- and intra-day coefficients of variation were less than 7%. The limits of detection and quantitation were 5 and 15 ng ml −1 , respectively. Drug levels were determined satisfactorily in three patients. A simple and reliable method was developed which uses a microvolume of plasma, particularly useful in low-weight children.

Effects of gender and phase of the menstrual cycle on the kinetics of ranitidine in healthy volunteers.

The present study was undertaken to determine if differences exist in the pharmacokinetic parameters of oral ranitidine caused by gender and stage of the menstrual cycle. The study was performed in two steps, in the first a pharmacokinetic study was performed on 10 men (average age 35.5 yrs) and 10 women (average age 34.7 yrs) during the follicular phase, and in the second the pharmacokinetic study was performed only on the same women in their luteal phase. Subjects received a tablet dose of 300 mg ranitidine, and blood samples were drawn at several times after its ingestion. Plasma ranitidine concentration was determined by high performance liquid chromatography. Comparison of the pharmacokinetic parameters of women and men revealed statistically significant differences both in distribution volume (Vd) with values of 2.0 and 6.3 l/kg, Area Under Curve (AUC) with values of 7312.15 and 11471.94 ng/ml/h, and clearance (CLt) with values of 0.65 and 0.59 l/kg/h, respectively. Several pharmacokinetic parameters in women were different in the follicular compared to the luteal phase; for example, Vd was 2.0 and 5.6 l/kg, AUC was 7312.15 and 5195.83 ng/ml/h, and CLt was 0.65 and 0.97 l/kg/h, in the respective phases. Moreover, the maximum concentration (Cmax) was 1086 ng/ml in the follicular vs. 864 ng/ml in the luteal phase. The first study detected differences between men and women in several pharmacokinetic parameters, mainly those indicative of drug availability, for example, Vd, AUC, and CLt. Comparison of data obtained in the follicular phase with those obtained in the luteal phase revealed differences in most pharmacokinetic parameters, which is seemingly indicative of the characteristic physiological changes associated with the luteal phase that largely affect the kinetics and availability of drugs such as ranitidine. Although it has been postulated that hormonal fluctuation within the menstrual cycle phase is the primary cause of documented gender differences in the pharmacokinetics and pharmacodynamics of drugs, further study of related factors is required to fully understand how gender and menstrual cycle rhythms affect the pharmacokinetic process in their entirety.

Clinical and laboratory characteristics of infectious mononucleosis by Epstein-Barr virus in Mexican children

Background: Infectious mononucleosis (IM) or Mononucleosis syndrome is caused by an acute infection of Epstein-Barr virus. In Latin American countries, there are little information pertaining to the clinical manifestations and complications of this disease. For this reason, the purpose of this work was to describe the clinical and laboratory characteristics of infection by Epstein-Barr virus in Mexican children with infectious mononucleosis. Methods: A descriptive study was carried out by reviewing the clinical files of patients less than 18 years old with clinical and serological diagnosis of IM by Epstein-Barr virus from November, 1970 to July, 2011 in a third level pediatric hospital in Mexico City. Results: One hundred and sixty three cases of IM were found. The most frequent clinical signs were lymphadenopathy (89.5%), fever (79.7%), general body pain (69.3%), pharyngitis (55.2%), hepatomegaly (47.2%). The laboratory findings were lymphocytosis (41.7%), atypic lymphocytes (24.5%), and increased transaminases (30.9%), there were no rupture of the spleen and no deaths among the 163 cases. Conclusions: Our results revealed that IM appeared in earlier ages compared with that reported in industrialized countries, where adolescents are the most affected group. Also, the order and frequency of the clinical manifestations were different in our country than in industrialized ones.BackgroundInfectious mononucleosis (IM) or Mononucleosis syndrome is caused by an acute infection of Epstein-Barr virus. In Latin American countries, there are little information pertaining to the clinical manifestations and complications of this disease. For this reason, the purpose of this work was to describe the clinical and laboratory characteristics of infection by Epstein-Barr virus in Mexican children with infectious mononucleosis.MethodsA descriptive study was carried out by reviewing the clinical files of patients less than 18u2009years old with clinical and serological diagnosis of IM by Epstein-Barr virus from November, 1970 to July, 2011 in a third level pediatric hospital in Mexico City.ResultsOne hundred and sixty three cases of IM were found. The most frequent clinical signs were lymphadenopathy (89.5%), fever (79.7%), general body pain (69.3%), pharyngitis (55.2%), hepatomegaly (47.2%). The laboratory findings were lymphocytosis (41.7%), atypic lymphocytes (24.5%), and increased transaminases (30.9%), there were no rupture of the spleen and no deaths among the 163 cases.ConclusionsOur results revealed that IM appeared in earlier ages compared with that reported in industrialized countries, where adolescents are the most affected group. Also, the order and frequency of the clinical manifestations were different in our country than in industrialized ones.

Cerebrolysin and morphine decrease glutathione and 5-hydroxyindole acetic acid levels in fasted rat brain

PURPOSEnThe aim was to evaluate if morphine sulphate combined with cerebrolysin enhances the risk of oxidative damage in the presence of moderate hypoglycaemia.nnnMETHODSnWistar rats under starvation for 48h received a single dose of 215 mg/kg cerebrolysin or 4 mg/kg morphine sulphate. Glutathione (GSH) and 5-hydroxyindoleacetic acid (5-HIAA) levels were measured in brain tissue, as well as lipid peroxidation, Na(+)-K(+) ATPase and total ATPase enzymatic activities, by fluorescence and spectrophotometric methods.nnnRESULTSnGSH and 5-HIAA levels decreased significantly (p<0.05) in animals which received cerebrolysin and morphine alone or combined. TBARS levels increased in all groups, but the values were statistically significant only in those animals that received cerebrolysin combined with morphine (p<0.05). Na(+)-K(+) ATPase and total ATPase activities decreased significantly in rats treated only with morphine, but the cerebrolysin and morphine groups showed a significant increase in these enzymatic activities.nnnCONCLUSIONSnResults suggest that cerebrolysin as well as morphine induced changes in cellular regulation and biochemical responses to oxidative stress induced by moderate hypoglycaemia in brain.

The Role of Dopamine and Its Dysfunction as a Consequence of Oxidative Stress

Dopamine is a neurotransmitter that is produced in the substantia nigra, ventral tegmental area, and hypothalamus of the brain. Dysfunction of the dopamine system has been implicated in different nervous system diseases. The level of dopamine transmission increases in response to any type of reward and by a large number of strongly additive drugs. The role of dopamine dysfunction as a consequence of oxidative stress is involved in health and disease. Introduce new potential targets for the development of therapeutic interventions based on antioxidant compounds. The present review focuses on the therapeutic potential of antioxidant compounds as a coadjuvant treatment to conventional neurological disorders is discussed.Dopamine is a neurotransmitter that is produced in the substantia nigra, ventral tegmental area, and hypothalamus of the brain. Dysfunction of the dopamine system has been implicated in different nervous system diseases. The level of dopamine transmission increases in response to any type of reward and by a large number of strongly additive drugs. The role of dopamine dysfunction as a consequence of oxidative stress is involved in health and disease. Introduce new potential targets for the development of therapeutic interventions based on antioxidant compounds. The present review focuses on the therapeutic potential of antioxidant compounds as a coadjuvant treatment to conventional neurological disorders is discussed.

Assessment of antioxidant effect of 2,5-dihydroxybenzoic acid and vitamin a in brains of rats with induced hyperoxia.

The aim of this study was to evaluate the effect of 2,5-dihydroxybenzoic acid, a salicylate derived from Acetyl salicylic acid (ASA) and vitamin A (vit A) on Na+, K+ ATPase enzyme and GSH levels in brain of rats exposed to hyperoxia (Hyp) as oxidant protocol. Rats were treated as follow: group I (control), group II (Hyp), group III (Hyp, ASA), group IV (vit A), group V (Hyp, vit A), group VI (Hyp, vit A, ASA). Vit A was given 5xa0days before and during Hyp, aspirin at the end of Hyp. Na+,K+ ATPase and total ATPase activity was significantly increased in group V. Levels of GSH showed a significant increase in group III, besides, levels of 2,5-dihydroxybenzoic acid as salicylate in plasma were significantly increased in group II. These results elucidate differences in the biochemical response of animal towards intake of various types of antioxidant substances, with increased GSH and salicylate in hyperoxia.The aim of this study was to evaluate the effect of 2,5-dihydroxybenzoic acid, a salicylate derived from Acetyl salicylic acid (ASA) and vitamin A (vit A) on Na+, K+ ATPase enzyme and GSH levels in brain of rats exposed to hyperoxia (Hyp) as oxidant protocol. Rats were treated as follow: group I (control), group II (Hyp), group III (Hyp, ASA), group IV (vit A), group V (Hyp, vit A), group VI (Hyp, vit A, ASA). Vit A was given 5xa0days before and during Hyp, aspirin at the end of Hyp. Na+,K+ ATPase and total ATPase activity was significantly increased in group V. Levels of GSH showed a significant increase in group III, besides, levels of 2,5-dihydroxybenzoic acid as salicylate in plasma were significantly increased in group II. These results elucidate differences in the biochemical response of animal towards intake of various types of antioxidant substances, with increased GSH and salicylate in hyperoxia.

Effect of prostaglandin E1 (PGE1) and sildenafil on serotonin metabolism and some oxidative damage markers in rat prostate gland and brain

The aim of this study was to evaluate the effect of sildenafil and prostaglandin E1 (PGE1) (drugs used in erectile dysfunction) on production of free radicals in prostate and brain of rat. A single dose of sildenafil (10u2003mgu2003kg−1) and PGE1 (20u2003μgu2003kg−1) was given to Sprague–Dawley rats (300u2003g weight) intraperitoneally. The levels of testosterone were measured in blood. Their brains and prostate glands were separated to measure lipid peroxidation, Na+ and K+ ATPase activity, reduced glutathione (GSH) and serotonin levels, by means of validated methods. The levels of testosterone increased slightly in animals treated with sildenafil and PGE1. The activity of total ATPase was increased in the prostate of animals treated with sildenafilu2003+u2003PGE1 but decreased in those that received sildenafil alone. PGE1 caused significant diminution of GSH levels in both organs. Sildenafil increased the levels of serotonine in brain, whereas in prostate they decreased instead. Our results suggest that sildenafil induced changes in GSH levels as well as in the serotonergic metabolism, alone or with PGE1 in prostate and brain, respectively. Thus, the combination therapy may be ideal to sustain the biochemical balance due to biphasic stimulation on brain and prostate.