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K Miyasato

Publications and source records attributed to K Miyasato.

At least 55 records · Page 3Linked to original sources

Abuse liability and pharmacodynamic characteristics of intravenous and inhaled nicotine.

The potential role of nicotine in tobacco dependence was investigated using the strategies of abuse liability assessment. Eight male volunteer cigarette smokers with histories of drug abuse resided on a research ward for the duration of the study. Each subject was tested with three doses of i.v. nicotine (0.75, 1.5 and 3.0 mg/10-sec infusion) and placebo each test day, and with three doses of inhaled nicotine, in the form of research cigarette smoke (0.4, 1.4 and 2.9 mg estimated yield) and placebo (sham-smoking), given on alternate test days. Each subject was tested on 4 days with both routes of administration, according to identical experimental protocols. Physiologic, subjective and observer data were collected at intervals ranging from 15 sec to 10 min beginning 10 min before drug administration and continuing for 30 min after administration. Both i.v. and inhaled nicotine produced dose-related increases in heart rate and blood pressure, and i.v. nicotine produced a transient bradycardia in four subjects during the first 30 sec after drug administration. Skin temperature was decreased by nicotine and pupil diameter was not consistently changed. Ratings of drug dose "strength" and drug "liking" were directly related to dose level whereas "desire to smoke cigarettes" was inversely related. Scores on the Morphine-Benzedrine Group (or Euphoria) scale of the Addiction Research Center Inventory were elevated by nicotine, and i.v. doses were identified frequently as cocaine. Signs and symptoms were similar for nicotine across the two routes of administration and included coughing, dizziness, nausea and relaxed feelings. Nicotine shared the pharmacologic profile of prototypic drugs of abuse. The study supports the hypothesis that the role of nicotine in tobacco dependence is equivalent to the role of other psychoactive drugs in substance abuse, e.g., to the role of cocaine in coca leaf use.

Adult↗

Cigarette smokers self-administer intravenous nicotine.

Human volunteers who smoked cigarettes were given the opportunity to press a lever that resulted in intravenous injections of saline or nicotine. Nicotine injections were taken in orderly patterns that were related to unit dose, whereas patterns of saline injections varied widely. Furthermore, the volunteers reported that nicotine produced subjective effects similar to those produced by administration of abuse drugs such as morphine or cocaine.

Adult↗

Reinforcements from the first drug experience can predict later drug habits and/or addiction: results with coffee, cigarettes, alcohol, barbiturates, minor and major tranquilizers, stimulants, marijuana, hallucinogens, heroin, opiates and cocaine.

The relationship between the reinforcing quality of the first drug experiences and eventual habits for a variety of drugs was studied in 42 male drug abusers who were predominantly opiate addicts. These subjects volunteered for drug studies carried out by the Addiction Research Center. The degree of reinforcement they derived from their first drug experience was related to their subsequent habit. This was true for alcohol, barbiturates, minor tranquilizers, cocaine, stimulants, marijuana, glue or solvents, hallucinogens, opiates other than heroin and heroin. Positive but non-significant correlations were found for coffee and major tranquilizers. The correlation for cigarettes was contrary to expectations. Of the components to the index of reinforcement, degree of liking of a drug on the first occasion was most related to the subsequent habit. The greatest initial reinforcement scores were found for heroin, cocaine and opiates other than heroin. drugs which were not well liked on the first occasion included major tranquilizers, cigarettes, coffee, and glue.

Adult↗