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E Balasubramaniam

Publications and source records attributed to E Balasubramaniam.

12 recordsLinked to original sources
PubMed1995

A sex-related difference in the neurobehavioral and hepatic effects following chronic endosulfan treatment in rats.

The neurobehavioral and hepatic effects following chronic endosulfan administration were studied in adult male and female rats. The neurobehavioral effect was determined by testing spontaneous motor activity, motor coordination and learning and memory processes in rats of either sex, 30 days after treating the animal orally with endosulfan (3.0 and 6.0 mg/kg per day). Mortality occurring during the treatment and body weight gain at the termination of treatment were also recorded. Liver weight and liver and serum concentrations of glutamic oxaloacetic transaminase, glutamic pyruvic transaminase and acetylcholinesterase were measured in order to determine the hepatotoxic effect of endosulfan. Body weight gain, motor coordination and acetylcholinesterase activity were unaltered in either sex. Learning and memory processes were impaired in both groups indistinguishably. Liver weight and liver and serum transaminases concentrations were increased more markedly in female than in male animals. A 30% mortality occurred in female group that received 6 mg/Kg of endosulfan. Endosulfan stimulated spontaneous motor activity more markedly in male than in female animals. These findings suggest that a sex-related difference seems to occur in the stimulation of spontaneous motor activity, liver injury and mortality that result from repeated exposure to sublethal doses of endosulfan in rats.

Acetylcholinesterase↗
PubMed1995

Cyclodiene insecticides-induced changes in the central depressive effect of chlorpromazine in rats.

Spontaneous motor activity (SMA), conditioned avoidance response (CAR), muscle coordination (MC) and pentobarbital sleep were tested in rats treated orally for 90 days with tolerated doses of the cyclodiene insecticides, aldrin (1 mg/kg) and endosulfan (2 mg/kg). The same tests were repeated in similarly treated animals after injecting chlorpromazine (4 mg/kg, i.p.). Both the insecticides shortened pentobarbital sleeping time indicating their microsomal enzyme inducing property. Aldrin suppressed SMA, CAR and MC, whereas endosulfan stimulated SMA, inhibited CAR and unaltered MC. However, their concurrent action with CPZ did not result in change in the central depressive effects of the latter, but its potency during the course of its action was altered. Its potency 15 min after injection was greater and 60-180 min later was lesser in these animals than that observed in control animals. This finding was interpreted to suggest that aldrin and endosulfan has quickened the biotransformation of CPZ and thereby shortened its duration of action. A temporary promotion of its potency was accounted to its active metabolites, since prior to inactivation, CPZ is known to be metabolized by the microsomal enzymes to active compounds.

Aldrin↗
PubMed1994

The neurobehavioural toxicity of endosulfan in rats: a serotonergic involvement in learning impairment.

Oral administration of the insecticide endosulfan (2 mg/kg per day) for 90 days in immature male rats resulted in an inhibition of pole-climbing escape response to electric shock (unconditioned) and avoidance response to buzzer (conditioned). These responses reflect respectively their learning and memory processes. The escape response but not the avoidance response was reinstated significantly by the 5-hydroxytryptamine (5-HT) depletor, p-chlorophenylalanine (PCPA, 100 mg/kg per day for 3 days). Endosulfan increased 5-HT concentrations in the cerebrum and midbrain regions. Protein content and acetylcholinesterase activity were unaltered in the brain. The spontaneous motor activity of these animals was stimulated. Their muscle coordination on rota-rod apparatus was unaffected. These findings were interpreted as an indication that a motivation deficit and not motor impairment was responsible for the inhibitory action of endosulfan on pole-climbing escape and avoidance responses. Thus, endosulfan was suggested to produce learning and memory deficit. A serotonergic involvement was significant in endosulfan-induced learning impairment and it appeared to be negligible in its memory disrupting action.

Acetylcholinesterase↗
PubMed1993

Behavioural and biochemical changes produced by repeated oral administration of the insecticide endosulfan in immature rats.

In order to study the response of rats to repeated administration of the insecticide, endosulfan during the period of growth to maturity, food intake, body weight gain, Spontaneous Motor Activity (SMA) and Muscle Coordination (MC) were determined at regular intervals in male immature Wistar rats treated with a tolerated dose of (2 mg/kg/day) orally for 90 days. Twenty-four h after the termination of the treatment, organ weight and protein concentrations were determined. The convulsive action of picrotoxin (4 mg/kg, ip) was tested in another endosulfan-treated group. Food consumption and body weight gain decreased parallely. No changes occurred in the body tissues but for liver which was enlarged and its protein, glutamic oxaloacetic transminase and glutamic pyruvic transaminase concentrations increased. The MC was unaffected. A stimulation of SMA occurred several days (75-90) after commencing treatment and these animals responded greatly than control animals to the convulsive action of picrotoxin. These findings indicated that although endosulfan produced anorexia, there were no signs of undernourishment and motor impairment in these animals. Its toxic action were confined chiefly to the liver and central nervous system.

Alanine Transaminase↗
PubMed1992

Evidence for a hazardous interaction between ethanol and the insecticide endosulfan in rats.

Protein supplemented diet was protective against the deleterious action of endosulfan on body growth and liver. Hepatomegaly and a reduction of body weight produced concurrently by endosulfan and ethanol were greater in male rats, suggesting that males are more susceptible than female rats to the metabolic stress caused by their interaction. Chronic endosulfan exposure resulted in a prolongation of ethanol sleeping time in female and not in male rats. This finding suggests failure of female rats to metabolize ethanol readily on account of their greater susceptibility than male rats to the hepatotoxic action of endosulfan.

Animals↗
PubMed1992

Effects of endosulfan and aldrin on muscle coordination and conditioned avoidance response in rats.

The deteriorative effects after chronic endosulfan exposure on muscle coordination, learning and memory of rats were compared with that produced by aldrin which has been reported to have similar effects in experimental animals. A rota-rod apparatus was used to study the muscle coordination and learning and memory were tested by recording the response to unconditioned and conditioned stimuli using a pole-climbing apparatus. Aldrin but not endosulfan inhibited motor coordination in both sexes. A greater motor deterioration occurred in male group. This finding, together with the previous data which shows inhibition by its metabolite of motor activity, suggests that its metabolic product is responsible for this action. Like aldrin, endosulfan inhibited both learning ability and conditioned avoidance response. A change in the activities of brain monoamines or inhibition of perception and reflexes or both were proposed for these behavioural effects, since the former was reported to be produced by both compounds and the latter was found to occur in aldrin treated rats.

Aldrin↗
PubMed1991

Are international anthropometric standards appropriate for developing countries?

To test the validity of using international standards as references for the assessment of nutritional status, investigations have been carried out on pre-school aged children selected from three distinct ecological environments in Papua New Guinea. Field work included anthropometric measurements (weight, height, triceps skin-fold, mid-upper-arm circumference, mid-upper-arm muscle circumference), together with pathological and clinical assessments (intestinal helminths, diarrhoea, splenomegaly, PEM signs). The findings indicate that any deviation below standard weight, height, and arm circumference is associated with greater prevalence of disease. International standards are therefore appropriate for preschool aged children in Papua New Guinea and by inference in other developing countries.

Anthropometry↗
PubMed1991

The determination of anthropometric cut-off points for protein-energy malnutrition using the maximum chi-squared statistical technique.

The Wellcome cut-off points for the classification of protein-energy malnutrition are arbitrary values. A simple technique, with the use of maximum chi-squared statistics, for the determination of cut-off points for anthropometric indicators for the assessment of malnutrition is presented. This technique has been applied to pre-school-age children in Lae, Papua New Guinea. In this population the cut-off points for the anthropometric indicators related to age, of body weight, height, triceps skinfold, arm circumference and arm muscle circumference, have been determined as 87%, 90%, 97%, 93% and 100%, respectively, of the international standards.

Age Factors↗