Janet S. Knisely

Perinatal substance abusers : psychological and social characteristics

Forty perinatal substance abusers were administered multiple psychosocial, addiction, and psychological measures before beginning treatment. Results indicate that these patients are limited intellectually, educationally, financially, and emotionally. Psychiatric comorbidity was high, with 45% having non-substance abuse axis I diagnoses and 75% having confirmed (by two or more tests) axis II pathology. The most frequently identified axis I disorders were depression and anxiety. The most frequently detected personality disorders were antisocial, borderline, paranoid, and dependent. The average IQ was 87 (low average range) and nearly one third of the sample were found to be somewhat impaired intellectually. These data suggest that treatment programs must take psychological characteristics into account if they are going to succeed in helping these women achieve and maintain abstinence.

Discriminative stimulus properties of toluene in the mouse

Little is known about the nature of the acute intoxication produced by exposure to high concentrations of toluene such as that which occurs with spills and in solvent abusers. The intoxication may be similar to that produced by classic central nervous system depressants such as the barbiturates. To investigate this hypothesis, drug discrimination procedures were used to compare the acute effects produced by toluene and pentobarbital (PB). Mice were trained to discriminate toluene (100 mg/kg, ip) from vehicle in a two-lever task in which responding was under the control of a fixed-ratio 20 (FR20) schedule of food presentation. Generalization tests were conducted after 20-min inhalation exposures to toluene (150-3600 ppm) and 20 min after injections with either PB (5-30 mg/kg) or morphine (3-20 mg/kg). Most mice generalized to inhaled toluene and to PB in a concentration- or dose-related fashion, but not to morphine. These results show that the effects of injected toluene can be established as a discriminative stimulus in mice, and that these stimulus effects are independent of route of administration. Shared discriminative stimulus properties with PB suggest that toluene produces an acute intoxication like that of other classic CNS depressants.

Discriminative stimulus properties of toluene in the rat

Rats were trained to discriminate toluene (100 mg/kg, IP) from vehicle in a two-lever operant task. Acquisition of the discrimination required a range of 85-219 training days. Injections of either methohexital (0.5-10 mg/kg) or oxazepam (0.5-20 mg/kg) produced toluene-lever responding in a dose-dependent fashion in most animals. The discriminative stimulus properties of toluene were not found to generalize to chlorpromazine (0.3-10 mg/kg). These results are consistent with those obtained in the mouse and provide further evidence that toluene has stimulus properties similar to those of CNS depressant drugs. These results further suggest that toluene may have drug abuse potential of the CNS depressant type.

Psychopathology in Substance Abusing Women Reporting Childhood Sexual Abuse

Abstract This study compared MMPI-2 profiles and evaluated the ability of the MMPI-2 and its two new post-traumatic stress scales (PK and PS) to discriminate women in outpatient substance abuse treatment reporting positive (n = 24) and negative (n = 69) child sexual abuse histories. T-tests revealed significantly higher mean scores for the sexual abuse group for the following scales: F, 1, 2, 3, 4, 6, 7, and 8. A discriminant analysis yielded a linear function of L, F, 3, 5, 8, and PK that correctly categorized 75% with positive histories and 77% with negative histories. The optimal cutoff PK score was 17, which correctly classified 75% and 46% of those reporting positive and negative abuse histories, respectively. These findings support early identification of abuse survivors among substance abusing women and suggests that the MMPI-2 may be useful in patient-treatment matching.

Social support and anxiety in pregnant drug abusers and nonusers: unexpected findings of few differences

Drug-abusing (n = 25) and nonusing (n = 55) pregnant women from a publicly supported prenatal clinic were tested for level of social support and of pregnancy anxiety during the last half of pregnancy. Differences found between the groups were fewer than expected. Drug abusers did not differ from nonusers in overall level of social support or in Appraisal, Belonging, or Tangible subscales. Abusers were found to report lower levels of self esteem; lower self esteem was predicted by drug abuse, having more children and lower socioeconomic status. Drug abusers did not differ from nonusers in their overall feelings of pregnancy anxiety, but they did indicate higher fears for themselves and for the baby, and there was a tendency for higher depression and withdrawal.

Assessment of the abuse potential of acetorphan, an enkephalinase inhibitor

The discriminative stimulus properties, reinforcing effects and physical dependence potential of acetorphan, a parenterally-active enkephalinase (E.C. 3.4.21.11) inhibitor, were assessed in the present studies. Rats trained to discriminate 2 mg/kg morphine from saline did not generalize to acetorphan at any dose tested (5-50 mg/kg). Acetorphan also had minimal reinforcing effects in rhesus monkeys. When acetorphan was substituted for cocaine, one dose (300 micrograms/kg per inj.) maintained responding somewhat above the range of vehicle values in only two of the four monkeys tested. In physical dependence studies, acetorphan also failed to produce opioid-like effects. In morphine-dependent monkeys and rats, acetorphan failed to suppress withdrawal. Additionally, there were no overt withdrawal signs observed following the termination of chronic acetorphan infusion in the rat. Together, these results indicate that acetorphan appears to have minimal abuse potential.

Attitude toward recovery and completion of a substance abuse treatment program

This study tested the ability of the Recovery Attitude and Treatment Evaluator (RAATE; Mee-Lee, Hoffmann, & Smith, 1992) to predict attrition from treatment for pregnant and postpartum substance abusing women. During the first month of treatment, the RAATE was completed by both the clinician and the patient. Three types of discharge status were considered: completion of the treatment program, dropping out of the program, and being administratively discharged. No group differences were found concerning the clinician version of the RAATE. Initial analyses of the patient version revealed that subjects who completed the program had lower ratings of resistance to treatment and continuing care compared to those who dropped out; further analysis suggested that those who completed less than 1 month of treatment exhibited the highest resistance. These results suggest the RAATE is a potentially effective tool for predicting early attrition from substance abuse treatment in this population.

Effects of intraperitoneal carbon monoxide on fixed-ratio and screen-test performance in the mouse☆

The behavioral effects of carbon monoxide (CO) administered via IP injection were investigated in the mouse. Mice were trained to lever press under a fixed-ratio (FR) 100 schedule of water reinforcement. Thirty-min test sessions were conducted either immediately or 30 min following IP injections of air (100 ml/kg) or CO (7.5, 15, 30, 50 or 100 ml/kg). CO produced a decrease in rates of responding which was exhibited earlier and lasted longer with increasing doses. Motor performance was also measured with the inverted-screen test following the same doses of CO at either 5, 15, 30, 60, 120 min or 24 hr post-injection. Performance was affected in a dose- and time-dependent fashion. Peak carboxyhemoglobin (COHb) levels were observed at 15 or 30 min and were 20%, 32%, 42%, 51% and 60% for 7.5, 15, 30, 50 and 100 ml/kg CO, respectively. COHb saturation alone was not always a good predictor of behavioral effects since both level and duration of exposure contributed to behavioral impairment. The results also show that the IP route can be used to study the toxicity of CO.

Effects of carbon monoxide in combination with behaviorally active drugs on fixed-ratio performance in the mouse

The effects of carbon monoxide (3.75, 7.5, 15 and 30 ml/kg, IP) alone and in combination with ethanol (1.1 g/kg), nicotine (1.1 mg/kg), caffeine (36.1 mg/kg), chlorpromazine (2.2 mg/kg), diazepam (10 mg/kg), pentobarbital (23.1 mg/kg), d-amphetamine (1.4 mg/kg) or morphine (13.3 mg/kg) were evaluated in mice. Animals were trained to lever press under a fixed-ratio 32 schedule of water reinforcement. Response rates following CO-drug combinations were compared with the expected additive effects determined by the sum of the effects of each agent administered alone. CO (15 and 30 ml/kg) in combination with ethanol produced supra-additive effects. CO-chlorpromazine and CO-d-amphetamine combinations often produced greater than additive response-rate suppression, although differences from additivity did not reach statistical significance. The effects on response rates following CO in combination with nicotine, caffeine, diazepam, pentobarbital, or morphine were additive. These results suggest that concurrent use of therapeutic or abused drugs and CO exposure may place an individual at higher risk for behavioral toxicity.