K. Gunnar Götestam

Self-administration of amphetamine analogues in rats ☆

In rats self-injecting amphetamine (0.25 mg/kg/injection) at a stable level during daily 3 hr sessions, three different amphetamine analogues )phenmetrazine, diethylpropion and fenfluramine) were substituted for amphetamine, one at a time on different experimental days. Phenmetrazine (1.0 mg/kg/injection) and diethylpropion (2.0 mg/kg/injection) were self-administered but not fenfluramine (in doses of 0.1, 0.5 and 2.0 mg/kg/injection). It is concluded that amphetamine, phenmetrazine and diethylpropion have reinforcing properties, whereas fenfluramine has not.

Covert extinction of amphetamine addiction

A covert extinction paradigm is developed and applied to four addicts, with long-term and heavy intravenous abuse of central stimulants. The technique included the imaginative presentation of the patients injection ritual, repeated 15 times a day. Three of the addicts have not taken amphetamines during a 9-month follow-up period.

The duration of tolerance to the anorexigenic effect of amphetamine in rats

Rats were given dl-amphetamine 16 mg/kg twice daily for 15 days. Complete tolerance to the anorexigenic effect of amphetamine developed from day 7–11. A single injection of 16 mg/kg amphetamine was given to the amphetamine pretreated rats and to saline pretreated controls at different time-points after withdrawal, and their food intakes were compared. Signs of tolerance were present at 16 but not 20 days after withdrawal.

Behavioral techniques in the treatment of drug abuse: An evaluative review☆

Abstract Studies of the use of behavior therapy of drug abuse are classified into (1) treatment of drug-taking behavior, (2) treatment of alternative behaviors, and (3) ward programs. Aversion therapies and extinction methods are included in the first category. Systematic desensitization, relaxation, covert conditioning, contingency contracting, and broad-spectrum approaches are classified into the second category. The ward program category consists of contingency management and token economy programs. The reviewed studies are evaluated as for patient characteristics, designs, assessment methods and follow-up. While the majority of studies show positive results the conclusions are restricted by methodological weaknesses. This points to the necessity of controlled studies both with single-subject and group designs.

Open-field behavior after intravenous amphetamine analogues in rats

A variety of behaviors were studied in an open-field setting after i.v. amphetamine (0.5, 2.0, 8.0 mg/kg), phenmetrazine (1.0, 4.0, 16.0 mg/kg), or fenfluramine (1.0, 4.0, 16.0 mg/kg). Amphetamine and phenmetrazine increased ambulation initially and rearing during the whole experiment, and decreased grooming. At 30 and 60 min, with the three higher doses of amphetamine, stereotyped behaviors interfered with and decreased both ambulation and grooming. Fenfluramine decreased ambulation, rearing, and grooming, and was the only drug to induce backing.The technique seems to be a simple and rapid method to establish dependence liability in amphetamine analogues. Interrater and test-retest reliability was established through ITV recordings.

Contingency management in a methadone maintenance treatment program

Abstract A contingency management program was developed for in-patients induced on methadone in a methadone maintenance treatment program. Before the behavioural program started, data were collected during a 4 week base-line period. After the program had been running for one week there was an “accidental reversal” during 3 weeks, and then a 12 weeks period with the program. During the program points were given contingent on target behaviours. The points gave access to privileges such as leave, passes and visitors. The target behaviours increased in frequency during the program, decreased during the “accidental reversal” and increased again when the program was reinstated.

The discriminative properties of amphetamine analogues tested in self-administering rats under maintained stimulus control

Abstract In a series of experiments, rats trained to self-administer amphetamine, were offered saline instead of amphetamine for self-administration during a 3 hr session. The self-administration behaviour was then extinguished. When a non-contingent injection of d -amphetamine (0.25 mg/kg), phenmetrazine (1.0 or 2.0 mg/kg), or diethylpropion (2.0 mg/kg) was given prior to self-administration of saline, the response rate was elevated, and the extinction delayed, in contradistinction to experiments which started with a non-contingent injection of fenfluramine (0.5 mg/kg) or saline. When fenfluramine instead of saline was offered for self-administration, non-contingent preinjections of amphetamine also increased the response rate. The maintenance of stimulus control in rats self-administering amphetamine was studied by lever contingency shifts. After a mean of 2.27 mg/kg of d -amphetamine, loss of stimulus control occured, and the rats developed a high rate of responding on only one lever. It is concluded that in the doses employed phenmetrazine and diethylpropion have reinforcing properties, whereas fenfluramine has not.

Acute tolerance to amphetamine in rats

Two groups of rats were given amphetamine intravenously at 5-min intervals (5 or 10 mg/kg/h) for 8h. Two control groups received saline infusions. On the second day a test dose of 10 mg/kg amphetamine was given to all groups. Body temperature, food intake, and motor behavior were registered every 30 or 60 min. The results showed the development of acute tolerance to the hyperthermic effect within 3–5 h. Tolerance was still visible on the 2nd day. There was also tolerance to the anorectic effect, which was evident on the 2nd day. One element of stereotyped behavior (swaying) also decreased during the amphetamine infusions.

A controlled study of two behavioral methods in the treatment of stuttering

The effectiveness of metronome-conditioned speech retraining in the treatment of stuttering was compared to shadowing and a waiting-list control condition. Subjects (n=5 in each group) received 20 sessions of individual therapy over a 3-month period. Assessment of percent nonfluency and number of words per minute during spontaneous speech and reading aloud were made before, after and at 14 months follow-up. Subjects treated with MCSR significantly reduced their degree of nonfluency during spontaneous speech and the shadowing subjects increased their rate of speech during reading aloud. The implications of these results are discussed.

The effect of non-contingent amphetamine injections on the extinction of food- and drug-reinforced lever pressing in rats

Abstract In a series of experiments rats were trained in either drug- or food-reinforced lever pressing. After this training period non-contingent injections of d -amphetamine (0.25 mg/kg), phenmetrazine (1.0 or 2.0 mg/kg), diethylpropion (1.0 mg/kg) or saline were given prior to self-administration of saline or responding without programmed consequences. Single doses of amphetamine, phenmetrazine, diethylpropion or saline were given before saline was offered for self-administration for 2 or 3 hr in rats previously made “dependent” on amphetamine. High rate of responding was observed when amphetamine was given before the session. Rats trained in food-reinforced lever pressing were given single doses of amphetamine, phenmetrazine or saline before the number of responses without programmed consequences were recorded for 3 hr. Low rate of responding was observed for all pre-treatment conditions. A rat trained in food-reinforced lever pressing was given a single dose of amphetamine (10 mg/kg) each day. Single doses of amphetamine, phenmetrazine or saline were given prior to sessions where the number of responses (without programmed consequences) were recorded for 3 hr. Low rate of responding was observed for all pre-treatment conditions. Rats pre-treated with single doses of amphetamine and trained in food-reinforced lever pressing were also given saline pre-treatment where lever pressing was followed by no programmed consequences, when single doses of amphethamine or saline were given before the sessions where the number of responses were recorded for 2 hr. High rate of responding was observed when amphetamine was given before the session. It is concluded that the increased rate of lever pressing for no programmed consequences after single doses of amphetamine is due to the experience of amphetamine during food-reinforced behavior, i.e. the drug acts as a discriminative stimulus for subsequent responding. Also the increased rate of saline self-injections after single doses of an amphetamine analogue can be explained in terms of the drug acting as a discriminative stimulus. It is therefore concluded that the increased rate of responding cannot be explained in terms of a general activity effect of amphetamine or amphetamine analogues.