ABSTRACT
BACKGROUND AND PURPOSE: Delta(9)-tetrahydrocannabinol (THC), the main psychoactive constituent of cannabis, accumulates in adipose tissue where it is stored for long periods of time. Here we investigated whether conditions that promote lipolysis can liberate THC from adipocytes to yield increased blood levels of THC. EXPERIMENTAL APPROACH: In vitro studies involved freshly isolated rat adipocytes that were incubated with THC before exposure to the lipolytic agent adrenocorticotrophic hormone (ACTH). A complementary in vivo approach examined the effects of both food deprivation and ACTH on blood levels of THC in rats that had been repeatedly injected with THC (10 mg.kg(-1)) for 10 consecutive days. Lipolysis promoted by ACTH or food deprivation was indexed by measurement of glycerol levels. KEY RESULTS: ACTH increased THC levels in the medium of THC-pretreated adipocytes in vitro. ACTH also enhanced THC release from adipocytes in vitro when taken from rats repeatedly pretreated with THC in vivo. Finally, in vivo ACTH exposure and 24 h food deprivation both enhanced the levels of THC and its metabolite, (-)-11-nor-9-carboxy-Delta(9)-tetrahydrocannabinol (THC-COOH) in the blood of rats that had been pre-exposed to repeated THC injections. CONCLUSIONS AND IMPLICATIONS: The present study shows that lipolysis enhances the release of THC from fat stores back into blood. This suggests the likelihood of 'reintoxication' whereby food deprivation or stress may raise blood THC levels in animals chronically exposed to the drug. Further research will need to confirm whether this can lead to functional effects, such as impaired cognitive function or 'flashbacks'.
Subject(s)
Adipocytes/metabolism , Adrenocorticotropic Hormone/pharmacology , Dronabinol/analogs & derivatives , Food Deprivation/physiology , Adrenocorticotropic Hormone/physiology , Animals , Cells, Cultured , Dronabinol/blood , Glycerol/metabolism , Lipolysis , Male , Rats , Rats, WistarABSTRACT
Nine males with mental retardation due to fragile X syndrome were compared to 9 males with mental retardation of other etiology. Subjects were compared on measures of personality, autistic features, and adaptive behavior. Results suggested that males with fragile X syndrome have a distinct psychological profile. In terms of DSM-III-R definitions, they had more autistic features, more schizoid features, and more schizotypal features. On measures of temperament, these males were more shy, more socially withdrawn, less energetic, and more emotional. The two groups did not differ with respect to adaptive behavior skills.
Subject(s)
Autistic Disorder/diagnosis , Fragile X Syndrome/diagnosis , Intellectual Disability/diagnosis , Personality Disorders/diagnosis , Social Behavior , Activities of Daily Living/psychology , Adult , Autistic Disorder/genetics , Autistic Disorder/psychology , Diagnosis, Differential , Fragile X Syndrome/genetics , Fragile X Syndrome/psychology , Humans , Intellectual Disability/genetics , Intellectual Disability/psychology , Male , Middle Aged , Personality Assessment , Personality Disorders/genetics , Personality Disorders/psychology , Psychiatric Status Rating Scales , Socialization , TemperamentABSTRACT
Although physicians routinely advise postcardiac event patients to stop smoking, the effect of a modified advice format targeting specific health concerns has not been investigated. Also, no studies of cessation advice with cardiac patients have used biochemical verification of self-reported abstinence. The present study included 48 veterans with a history of smoking and cardiac problems; of these, 31 were smoking and 17 were abstinent at initial assessment. Alveolar carbon monoxide (COa) levels served to: (1) augment cessation advice by demonstrating smoking risks and cessation benefits specific to cardiac patients and (2) verify self-report. At 12 months followup, following cessation advice, 18% of the abstinent subjects had resumed smoking while none of the smokers had become abstinent. Those who maintained abstinence significantly increased their estimates of the contribution of smoking to their cardiac problems whereas those who continued to smoke showed no change.
