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V A Colotla

Publications and source records attributed to V A Colotla.

8 recordsLinked to original sources
PubMed1992

Adipsic, but not anorectic, effect of fluprazine hydrochloride in rats.

The present experiment explored the anorectic and adipsic effects of fluprazine hydrochloride, a phenylpiperazine compound. Thirty-eight albino rats were randomly assigned either to a control saline group (six rats) or to groups (eight subjects each) receiving an IP dose of fluprazine in saline (1.25, 2.5, 5 or 10 mg/kg). No anorectic effect of the drug doses was observed 30, 60, 90, 120, 180 and 240 min, and 24 h after drug injection. However, water drinking was significantly decreased 30 min after drug administration, with 5 and 10 mg/kg, compared to saline.

Analysis of Variance↗
PubMed1990

Behavioral and biochemical correlates of chronic administration of quipazine.

In Experiment 1 groups of rats received single injections of 1, 3, 10, 20 or 40 mg/kg quipazine, and their total 24-hr food and water intake after a 24-hr deprivation period was recorded; there was a dose-related reduction of both food and water intake. In Experiment 2 a group of 15 rats received 5 mg/kg/day, SC quipazine during 29 days, and a control group received saline injections. During treatment, all animals were exposed to a 24-hr food and water deprivation schedule, alternated with 24 hr of free access. Food and water consumption was measured 2 and 24 hr after drug injection; regional 5-HT concentrations were determined at 1 and 13 treatment days by fluorometric assay. Beginning the first treatment day, food and water intake decreased, but by the 13th day the quipazine group had returned to normal ingestion levels. 5-HT concentrations were increased in cerebellum and cortex in acute conditions, but after 13 days they had decreased in cerebellar samples. In Experiment 3 we found that the effects of quipazine on food and water ingestion were recovered after 14 days of discontinuing chronic drug administration.

Animals↗
PubMed1990

Biphasic changes in mouse motor activity during exposure to toluene.

There are few careful studies of the effects of solvents on unlearned animal behavior during acute exposure, despite the importance of the prevention of acute behavioral or neurological effects in the workplace. To examine the effects of toluene on the locomotor activity of mice, we divided a plastic vacuum desiccator into six wedge-shaped compartments with diffusing plena above and below. A phototransistor in each wedge measured the movement of individual mice, thus each mouse could serve as its own control. Six groups of six mice were exposed to each of five concentrations of toluene (300-3000 ppm) or air in a Latin-square design for 1 hr on Tuesdays and Fridays. Individual animals differed in their sensitivity to toluene, and the use of each subject as its own control permitted the detection of effects at lower concentrations. The magnitude of the effect was related to concentration, the duration of exposure, and the control rate of activity. Activity increases were obvious at 560 ppm, and decreases at 3000 ppm. The concentrations at which these reversible activity increases occurred are the lowest reported to date and are only slightly greater than those that have been reported to alter human reaction time. This preparation displays sensitivity comparable to that observed in published studies of the effects of toluene on learned behavior in the rat.

Analysis of Variance↗
PubMed1979

Effects of solvents on schedule-controlled behavior.

Operant conditioning techniques have been shown to be sensitive to the acute effects of industrial solvents. In the first experiment, five rats trained in a multiple schedule with a fixed-ratio (FR) 10 component and a differential reinforcement of low rates (DRL) 20-sec component, with a time out 60-sec between reinforcement periods, were exposed to 0.25, 0.50, 1 and 2 ml of toluene in the experimental chamber. The effects were dose-dependent, with an increase in rate in the DRL component and a decrease in FR responding. A second experiment assessing the effects of chronic exposure to thinner in the acquisition of a timing behavior in rats showed an impairment in DRL learning after 4, 8 or 16 weeks of exposure to the solvent: however, rats having a resting period did not differ from control animals. Whereas this finding suggests a reversible impairment in the acquisition of a complex behavior, further research is needed to achieve more definitive conclusions.

Administration, Inhalation↗
PubMed1971

Stimulus and subject control of schedule-induced drinking.

Responding in three food-deprived rats was reinforced on schedules in which reinforcement periods (fixed-ratio 1 or 2 for 1, 3, 6, 9, 14, or 21 reinforcers) alternated with extinction intervals. Schedule-induced drinking occurred and was mostly confined to the onset of extinction intervals. Drink durations were longer after 21-pellet meals but were not reliably different after 1, 3, 6, or 9-pellet meals. When termination of the extinction intervals was response dependent, schedule-induced drinking diminished until minimum extinction intervals of 15, 30, and 60 sec were introduced.

Animal Nutritional Physiological Phenomena↗
PubMedDate not supplied

Effects of MPTP on locomotor activity in mice.

Thirty-two mice were randomly assigned to one of 4 groups of 8 animals each: the first received IP saline injections and the other 3 groups received 10, 20 or 30 mg/kg MPTP. Each dose or saline was administered 3 times in 3 consecutive days and locomotor activity was measured during the next 3 days. In addition, the animals were observed in 2 trials in a rotating rod (Rotarod) and a grip test. The 2 highest doses of the drug produced significant increases in locomotor activity. In the other two behavioral tests, the highest dose of MPTP significantly reduced the capability of the animals to remain on the Rotarod on the grid.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗