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Biomedical subjects

B Costall

Publications and source records attributed to B Costall.

At least 289 records · Page 16Linked to original sources
PubMed1973

The role of the substantia nigra in the locomotor stimulant action of amphetamine.

1. The electrolytic brain lesion technique was used to evaluate the role of the substantia nigra in the mediation of the locomotor stimulant effect of (+)-amphetamine in the rat. The effect upon the results of variations in strain and basal activity levels of the rats was assessed.2. In the immediate postoperative phase the lesioned animals developed spontaneous stereotyped behaviour patterns which were more intense in rats of initially high basal activity. Activity was depressed at this stage and only that of the low activity animals was stimulated by amphetamine.3. After the 2nd postoperative day rats with lesions of the substantia nigra developed hyperactivity, but this was only maintained in rats initially of low basal activity. During this stage the locomotor stimulant effect of amphetamine (1.0 mg/kg) was apparent and after the 9th postoperative day animals generally displayed an increased sensitivity to the drug effect.4. The involvement of the substantia nigra with the control of locomotor activity is indicated but its integrity would not appear essential for the mediation of the locomotor stimulant effects of amphetamine.

Animals↗
PubMedDate not supplied

Neuroleptic antagonism of dyskinetic phenomena.

The bilateral intrastriatal administration of dopamine to guinea pigs pretreated with nialamide-induced dyskinesias characterized by gnawing, biting and licking reactions, acute twisting of the head and neck, whole body or head and neck rocking movements, and a hyperactive state. Hyperactivity was inhibited by the peripheral administration of large doses of many neuroleptic agents, e.g. haloperidol, fluphenazine, but only pimozide and oxiperomide inhibited the other forms of dyskinetic movements. This was not due to a peculiar depressant effect of these agents in the guinea pig since haloperidol was shown to be equipotent to oxiperomide and of greater potency than pimozide both in causing catalepsy and antagonising amphetamine sterotypy...

Adrenergic alpha-Antagonists↗
PubMedDate not supplied

Actions of sulpiride and tiapride in a simple model of anxiety in mice.

A two-compartment activity box is described in which the actions of anxiolytic compounds may be readily detected. The box is designed with a partition which divides a dimly-lit black area and a brightly-illuminated white area. Free access to each section is enabled by means of a small opening in the partition. Measures of locomotion and rearing are recorded as well as transitions from black to white and vice versa. Time spent in each section is also measured. In this situation mice demonstrated a clear preference for the dim black section, a finding not inconsistent with the nocturnal nature of this species. By contrast, treatment with diazepam (0.125-5 mg/kg) or triazolam (0.01-0.1 mg/kg) produced a significant increase in activity in the white section. Locomotion and rearing in the black section showed a corresponding decrease. Sulpiride (0.5-20 mg/kg) and tiapride (0.5-40 mg/kg) had similar effects. These actions would appear to be independent of their effects on general activity, as amphetamine (1.25-2.5 mg/kg) increased and haloperidol (0.05-0.2 mg/kg) decreased overall exploratory behaviour in a non-selective manner. These data suggest the "two-compartment activity box" to be a model sensitive to the actions of clinically-active anxiolytics.

Amphetamine↗
PubMedDate not supplied

Initiation and maintenance of oral ethanol self-administration in female Sprague-Dawley rats.

Group-housed female Sprague-Dawley rats were trained to self-administer 5% ethanol (v/v) in a large self-administration chamber (100 x 40 x 40 cm) following three different initiation methods. The procedures were 1) an ethanol injection procedure, 2) a sucrose substitution procedure, and 3) a prandial drinking technique. Only the prandial drinking method served to maintain responding for ethanol in the absence of water deprivation or sweetening of the alcohol solution. Rats trained using this technique showed a large preference for 5% ethanol over water and a significant increase in locomotor activity while responding for 5% ethanol but not while responding for water. When the concentration of ethanol was increased from 1% to 32%, the amount of ethanol ingested increased up to a maximum of 1.233 +/- 0.3 g/kg of 32% ethanol, and response rates and number of ethanol deliveries followed an inverted U-shaped curve. Appreciable blood ethanol levels were detected immediately following self-administration of 8% ethanol. These results show that, in female Sprague-Dawley rats under the experimental conditions described, the prandial drinking technique was the most effective in inducing stable oral ethanol self-administration and suggest that under these conditions and in these subjects ethanol was acting as a positive reinforcer.

Alcohol Drinking↗
PubMedDate not supplied

The 5-HT1A receptor agonist 8-OH-DPAT reduces ethanol intake and maintained behavior in female Sprague-Dawley rats.

Agents affecting serotonergic (5-hydroxytryptamine, 5-HT) function influence ethanol consumption in rats and primates. In the present study female Sprague-Dawley rats were trained to orally self-administer 8% ethanol (v/v) in a large operant chamber in a 60-min test period by a prandial drinking technique. The number of response, ethanol reinforcers (dipper deliveries), and ethanol consumption (g/kg) were measured following administration of the 5-HT1 A agonist 8-OH-DPAT (0.001 1.0 mg/kg, ip) 30 min prior to testing. Locomotor activity (LMA) was also measured to assess activity changes induced by 8-OH-DPAT. 8-OH-DPAT selectively reduced ethanol ingestion from 17.1 +/- 3.2 dipper deliveries under vehicle conditions to 6.6 +/- 3 at a dose of 0.1 mg/kg. Higher doses of 8-OH-DPAT (0.5 and 1.0 mg/kg) significantly reduced both ethanol ingestion and LMA. Lower doses of 0.001-0.01 mg/kg of 8-OH-DPAT were without effect on ethanol intake and maintained behavior. These results demonstrate that, under the present experimental conditions, the 5-HT1A receptor agonist 8-OH-DPAT reduced ethanol self-administration in the rat, and support a role for 5-HT1A receptors in the mediation of ethanol reinforcement.

8-Hydroxy-2-(di-n-propylamino)tetralin↗