Search PubMed⌕ Search

Biomedical subjects

S J Cooper

Publications and source records attributed to S J Cooper.

At least 235 records · Page 13Linked to original sources
PubMed1979

Effects of spiperone on feeding performance in a food preference test.

Spiperone reduced latency to feed and prolonged the total duration of feeding in a food-preference test in which novel and familiar foods were presented simultaneously to food-deprived rats. The increase in feeding duration could be accounted for in terms of an increase in time devoted to eating the novel foods, leaving the time devoted to eating the familiar food relatively unaltered. However, closer analysis of the data revealed that, at the level of mean duration of individual eating episodes, spiperone prolonged the eating-episode duration equally for both novel and familiar foods. This apparent paradox was resolved by noting that whilst spiperone did not alter the number of eating episodes in the test, it did alter the ratio of eating episodes in favour of novel foods. The data was incorporated into a control system model which depicts actions of spiperone in the food-preference situation with total eating duration as the final behavioural output.

Animals↗
PubMed1979

Chlordiazepoxide-induced disruption of discrimination behaviour: a signal detection analysis.

To assess the effects of chlordiazepoxide (CDP) on a stable discrimination performance, eight rats were trained on a simple brightness discrimination and injected with three dosages (0, 5, and 10 mg/kg) once performance was stable. Signal detection analysis of the results was used to differentiate sensory from motor/responsivity effects of the drug. At 5 mg/kg, CDP increased general responsiveness which is consistent with the hypothesis that CDP disinhibits responding. At 10 mg/kg, however, this effect on responsivity was reversed and there was also a suppression of stimulus sensitivity.

Animals↗
PubMed1979

Feeding parameters with two food textures after chlordiazepoxide administration, alone or in combination with d-amphetamine or fenfluramine.

Chlordiazepoxide (5.0, 10.0 mg/kg) reduced the rate of eating and extended the duration of feeding in a 10 min feeding test. It also reduced the latency to feed. Both fenfluramine (1.0 mg/kg) and d-amphetamine (0.25 mg/kg) acted to reduce food intake, but by differing mechanisms. Fenfluramine reduced eating rate without affecting eating duration, whilst d-amphetamine reduced eating duration without reducing eating rate. The effects of chlordiazepoxide on feeding parameters were generally additive with those of either d-amphetamine or fenfluramine, whenever chlordiazepoxide was given in combination with one of the anorectic drugs. Food texture affected feeding behaviour; rats ate standard diet in pellet form faster than powdered food, although they spent longer eating the powdered food. Textural differences did not significantly interact with the changes in feeding responses induced by the 3 drugs, except that latency to eat after either d-amphetamine or fenfluramine injection, when pellets were available, was significantly prolonged. Characterising drug effects on feeding in terms of a 2-dimensional matrix of eating rate and duration is recommended, rather than relying solely on amount of food consumption as the measure of drug effects.

Animals↗
PubMed1979

Water intake and time course of drinking after single or repeated chlordiazepoxide injections.

Chlordiazepoxide (5.0, 10.0 or 15.0 mg/kg) was given to rats either acutely or for 9 consecutive days. Its effects were examined in a 15-min drinking test in which latency to drink, volume of water consumption and the time-course of drinking were measured. Chlordiazepoxide (10.0 mg/kg) produced the strongest stimulant effect on drinking and enhanced the frequency of occurrence of drinking both at the beginning and at the end of the test period. Chlordiazepoxide (15.0 mg/kg) delayed the onset of drinking and its peak effect was observed later than for other injection conditions. Single and repeated administration of chlordiazepoxide had the same effects on the measures taken in the test. Initial sedation to the drug treatment and subsequent tolerance to this effect were not, therefore, factors influencing the drug effects observed in this experiment. Possible mechanisms underlying the stimulation of drinking by chlordiazepoxide are considered.

Animals↗
PubMed1979

Food-choice in a food-preference test: comparison of two mouse strains and the effects of chlordiazepoxide treatment.

In male mice of the C57 strain, chlordiazepoxide (CDP) (2.5, 5.0 and 10.0 mg/kg) reduced the latency to begin eating and prolonged the total time devoted to eating in a food-preference test. The increase in feeding duration arose from an increase in the mean duration of individual eating episodes and not from a change in the number of episodes that were initiated. In contrast, in male mice of the A2G strain CDP (at the same dose levels) did not reduce the latency to begin eating and only prolonged the total time devoted to eating at a single dose level (5.0 mg/kg). The two strains differed in their choice between novel and familiar foods that were concurrently available in the test. The A2G mice virtually ignored the palatable novel foods and devoted all their feeding to the familiar food. The C57 strain, however, spent more time eating the novel foods than the familiar food. CDP at all doses increased the duration of feeding devoted to familiar food in the C57 animals, but did not increase feeding duration in the A2G mice. However, CDP (10.0 mg/kg) increased the time spent eating novel foods in both strains to the same degree. Possible mechanisms underlying the effect of CDP on food-preference behaviour in mice and accounting for the strain difference in response to CDP are considered.

Animals↗
PubMed1979

Food and water intake in the non-deprived pigeon after chlordiazepoxide administration.

Food and water intake were measured in non-deprived pigeons over a 4h period during daytime. Under control conditions, the ratio of food to water intake was approximately 1:1, and both intakes were a simple linear function of time. Chlordiazepoxide (10 mg/kg, i.m.) doubled the mean amount of food intake, whilst leaving water intake unchanged. This is a first indication that chlordiazepoxide can selectively stimulate appetite for food in an avian species. Some birds showed sedation following a first acute injection; its duration was shortened after repeated injections, and the hyperphagic response to the drug was revealed.

Animals↗
PubMed1979

Effects of acute or chronic administration of chlordiazepoxide on feeding parameters using two food textures in the rat.

The effects of acute or chronic administration of chlordiazepoxide on several feeding parameters were studied in the rat. Given acutely, chlordiazepoxide reduced the rate of feeding, at lower dose levels (5.0 or 10.0 mg kg-1) tended to prolong feeding duration, and at a higher dose (15.0 mg kg-1) reduced the amount of food intake. Food texture can influence feeding parameters too; but the effects of the drug did not interact with the effects of food texture. After 9 daily injections of the drug, there were several indications of the development of tolerance to the effects of the drug on the feeding parameters. A possible role of 5-HT mechanisms in the reduction of eating rate produced by the drug is considered.

Animal Feed↗
PubMed1978

Enhanced choice of familiar food in a food preference test after chlordiazepoxide administration.

Chlordiazepoxide (5.0 and 10.0 mg/kg) increased the time spent eating familiar laboratory chow, in a food-choice test in which both familiar and novel food objects were available. Chlordiazepoxide did not affect the feeding response to the novel food. Prior handling of the rats and repeat testing affected feeding responses in the test, although in ways which were different from and independent of the effect of chlordiazepoxide. Chlordiazepoxide may facilitate feeding responses by a direct enhancement of feeding motivation, and not necessarily secondarily by either a release of suppression of feeding or as attenuation of anxiety evoked by unfamiliarity.

Animals↗