Search PubMed⌕ Search

Biomedical subjects

W W Beatty

Publications and source records attributed to W W Beatty.

At least 91 records · Page 5Linked to original sources
PubMed1982

Septal lesions increase play fighting in juvenile rats.

Play fighting is a behavior exhibited by juveniles of many mammalian species, but the neurology of this behavior is poorly understood. In the present study lesions of the septal area or control operations were performed in rats at 23 days of age and social play was studied between the ages of 27-41 days of age. Septal lesions increased the frequency of play fighting and play initiation in both sexes; within the lesion and control groups males played more frequently and initiated more play bouts than females. Animals with septal lesions were somewhat lighter in body weight than controls, but since play frequency and body weight were not associated, it is unlikely that changes in body weight caused by the lesions are responsible for the effects of the lesions on play.

Aggression↗
PubMed1982

Scopolamine does not disrupt spatial working memory in rats.

The importance of cholinergic systems for spatial working memory was examined by injecting scopolamine at varying times during a 5 hr-long retention interval imposed between the rat's fourth and fifth choices in an 8 arm maze. Regardless of whether or not the testing procedure required the rats to adopt a spatial solution for the task, scopolamine (1.0-5.0 mg/kg) did not impair retention in a manner that was suggestive of an effect on working memory. Modest deficits observed in some conditions appeared to result from drug effects on performance. Previous findings of impaired acquisition of accurate spatial behavior by scopolamine-treated rats evidently reflect an influence of the drug on physiological systems other than those necessary to maintain working memory for spatial information.

Animals↗
PubMed1982

Stereotyped behavior elicited by amphetamine in the rat: influences of the testes.

Castrating male rats in adulthood increased the duration of stereotyped behavior in responses of 5 mg/kg injections of d-amphetamine sulfate; exogenous treatment with testosterone propionate (TP) reversed this effect. Ovariectomy in adulthood had no effect on stereotypy, but TP injections reduced stereotyped responding by ovariectomized females. Thus testosterone exerts comparable effects on stereotypy elicited by amphetamine in both sexes. Males castrated at 1, 6 or 10 days of age but not males castrated in adulthood displayed levels of stereotyped behavior comparable to those of ovariectomized females when all animals were given TP in adulthood. Control experiments indicated that age of castration rather than time since castration was the critical factor, implying that secretions of the testes early in life exert effects on systems that regulate the responses of adults to amphetamine.

Animals↗
PubMed1982

Psychomotor stimulants, social deprivation and play in juvenile rats.

Treatment with d-amphetamine (0.125-1 mg/Kg) or methylphenidate (0.5-4 mg/kg caused dose-dependent decreases in play fighting in juvenile rats which were independent of sex and strain. Although brief social isolation profoundly increased play fighting, qualitatively similar drug effects on play were observed in socially housed and isolated animals. By contrast, at the highest doses tested both amphetamine and methylphenidate increased social investigation, but only if the rats were socially isolated. Stimulation of catecholamine systems is evidently incompatible with the expression of playful behavior.

Aggression↗
PubMed1982

Naloxone and play fighting in juvenile rats.

According to the opioid hypothesis of social attachment opiate receptor blockade should increase the need for social contact. Yet naloxone reduces play fighting [11], a major form of social interaction in young rats. This observation might be reconciled with the opioid attachment hypothesis if it could be shown that naloxone produced compensatory increases in other social activities or if naloxone shortened play fighting bouts without reducing their frequency. In the present experiment naloxone reduced play fighting in a dose-dependent fashion. However, the frequency of play bouts was reduced, their duration unchanged and no compensatory increase in social sniffing and grooming was observed. In addition, naloxone inhibited rearing almost as potently as it affected play fighting.

Aggression↗
PubMed1981

Gonadectomy and sex differences in the behavioral responses to amphetamine and apomorphine of rats.

Following treatment with 5 mg/kg d-amphetamine sulfate or 2 mg/kg apomorphine hydrochloride female rats displayed more intense and longer lasting stereotyped behavior than males. Gonadectomy did not affect the display of stereotyped behavior induced by either drug in either sex. A lower dose of amphetamine (1 md/kg) caused greater stimulation of locomotor activity in females than in males. Castration of males had no effect, but ovariectomy blocked the stimulating effect of amphetamine on activity. By contrast, low doses of apomorphine depressed activity in a dose-dependent manner that was somewhat greater in ovariectomized females than in the other groups. These data add to the growing body of literature demonstrating that gonadal hormones modulate the activity of brain dopamine systems.

Amphetamine↗
PubMed1981

Anesthetics and electroconvulsive therapy seizure duration: implications for therapy from a rat model.

The anesthetic agents methohexital (Brevital), Innovar, and ketamine (Ketaject) were examined for their effect on seizure duration following electroconvulsive stimulation in a rat model of electroconvulsive therapy (ECT). Compared to unanesthetized control animals, methohexital anesthesia shortened seizure duration by 42%, ketamine anesthesia tended to increase seizure duration, and Innovar anesthesia had no effect on duration of seizures.

Anesthesia, General↗
PubMed1978

Open-field and avoidance behavior after neostriatal lesions in male and female rats.

The behavioral effects of lesions of the anterodorsal or posteroventral parts of the caudate-putamen were studied in adult male and femle rats that were gonadectomized or left untreated prior to brain surgery. Anterodorsal (ADC) lesions consistently impaired acquistion of one-way avoidance behavior and tended to interfere with the development of a two-way avoidance response; comparable effects were observed in gonadectomized and intact animals of both sexes. By contrast, ADC lesions increased activity in the open field only in intact females and increased rearing only in ovariectomized females. Posteroventral caudate (PVC) lesions caused transient aphagia and adipsia in both sexes but did not consistently affect open-field activity or the acquistion of one-way avoidance responses by either sex. These lesions profoundly impaired acquistion of shuttle box avoidance responses by intact males. By contrast, castrated males and intact and ovariectomized females with PVC lesions avoided normally in the shuttle box. The present results suggest that localization of behavioral functions within the striatum differs with the sex of the subject, in part because of activational effects of gonadal hormones.

Animals↗