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D R Cherek

Publications and source records attributed to D R Cherek.

83 records · Page 5Linked to original sources
PubMed1982

Schedule-induced cigarette self-administration.

Cigarette self-administration was studied in a controlled laboratory setting by automated recording of the various components of smoking behavior. The effects of intermittent scheduled monetary reinforcement presentation on cigarette smoking was determined in an attempt to demonstrate schedule-induced cigarette self-administration. Schedule-induced cigarette self-administration was indicated by changes in some of the topographical components of cigarette smoking behavior, e.g., puff frequency and mean puffs per cigarette, as a function of changes in the fixed interval value of a monetary reinforcement schedule. While the number of cigarettes smoked changed only slightly following changes in the FI value of the monetary reinforcement schedule, other components of cigarette smoking behavior, particularly puff frequency and mean puffs per cigarette, were significantly altered. Cigarette puffs were most likely to occur immediately following monetary reinforcement presentation or in the initial segment of the next fixed interval. The demonstration of schedule-induced self-administration in human adds another common factor found to influence infrahuman and human drug self-administration.

Behavior↗
PubMed1982

Effects of increasing urinary pH on cigarette smoking.

We evaluated the effects of increasing urinary pH on sensitive automated measures of cigarette smoking behavior. Urine was alkalized by oral doses of 50 or 75 mg/kg sodium bicarbonate. Measurements of cigarette smoking behavior included the number of cigarettes smoked and automated measures of puff frequency and duration. The sodium bicarbonate resulted in little or no change in the number of cigarettes smoked, but in five of the seven subjects frequency and duration of cigarette puffs after sodium bicarbonate decreased 10% to 15%. The small decreases in cigarette smoking brought about by sodium bicarbonate cannot be expected to have significant overall effects.

Behavior↗
PubMed1982

Effects of cigarettes on saliva cortisol levels.

We determined the effects of cigarette deprivation and smoking on saliva cortisol levels in the presence and absence of an operant, monetarily reinforced work task. Subjects were randomly exposed to the following four experimental conditions over successive sessions: no smoking, smoking, no smoking + work, and smoking + work. Measurements of cortisol levels in saliva were determined before and after each daily session. Saliva cortisol levels declined from the beginning to the end of sessions and the end-of-session saliva cortisol levels were not affected by any of the four experimental conditions. Increased cigarette smoking in the presence of the work task also did not affect saliva cortisol levels. Our data do not support: reports of increased cortisol levels as a consequence of smoking or theories relating cortisol and endorphin release to nicotine habituation.

Adult↗
PubMed1981

Effects of smoking different doses of nicotine on human aggressive behavior.

A new methodology was employed to study the effects of drugs on human aggressive behavior in a laboratory situation. The effects of not smoking, smoking a low nicotine dose (0.42 mg/cigarette), and smoking a high nicotine dose (2.19 mg/cigarette) on human nonaggressive and aggressive responding was determined. A nonaggressive response, which resulted in the accumulation of money, was continuously available to the subject. Two different aggressive responses were also available: the ostensible subtraction of money from, and the ostensible presentation of a 1-s blast of white noise to a (fictitious) person. Aggressive responding was elicited by subtracting money from the research subjects, which was attributed to a fictitious person paired with the research subject randomly each day. Nicotine, administered with experimental cigarettes, produced dose-dependent decrease in both types of aggressive responding elicited by low or high frequency subtractions of money attributed to another person. Generally, the more aggressive response option, i.e., subtraction of money from another person, decreased more following nicotine administration. Smoking the same doses of nicotine increased nonaggressive monetary reinforced responding. This indicates that the suppressant effects of nicotine on aggressive responding was not due to a non-specific depressant action.

Aggression↗
PubMed1981

Effects of ammonium chloride on urinary pH and cigarette smoking behavior.

We determined the effects of acidification of urinary pH on cigarette smoking behavior to assess the postulated relationships between stress, urinary pH, and cigarette smoking. Urine was acidified by short-term administration of 12.5, 25, and 50 mg/kg ammonium chloride and long-term administration of 50 mg/kg ammonium chloride. Measurements of cigarette smoking behavior included the number of cigarettes smoked as well as automated measures of puff frequency and duration. Short- and long-term administration of ammonium chloride induced decreases in urinary pH but failed to induce any substantial changes in number of cigarettes smoked, puff frequency, or puff duration.

Ammonium Chloride↗
PubMed1980

Chronic delta 9-tetrahydrocannabinol administration and schedule-induced aggression.

The effects of 0.5 mg/kg and 1.0 mg/kg of delta 9-tetrahydrocannabinol (delta 9-THC) on key-pecking maintained by a response-initiated fixed interval (FI) schedule of food presentation and schedule-induced aggression in the pigeon were studied. Initially, following the administration of delta 9-THC both the rate of key-pecking and attack responding were markedly reduced. Over sessions, tolerance developed to the suppressant effect on key-pecking, with the rate returning to the predrug level. The suppressing effect of delta 9-THC on the rate of attack remained at or near zero throughout the series of delta 9-THC injections.

Aggression↗
PubMed1973

Responding maintained by the opportunity to attack during an interval food reinforcement schedule.

Pigeons responded in a two-key situation. Responses on the right key (food key) were reinforced with food presentation on a response-initiated fixed-interval schedule, (i.e., first response after a fixed period of time was reinforced); responses on the left key (target key) were reinforced on a fixed-ratio schedule (i.e., every nth response was reinforced) with the presentation of a target bird that could be attacked. When the interval value of the food reinforcement schedule was varied from 1 min to 5 min, both the rate of attack responding on the target bird and the rate of responding on the target key were a function of the interval value. Responding on the target key was not maintained by the stimulus change associated with target availability, and was successively extinguished and reconditioned by removing and returning the target bird to the restraining box. When food was delivered independently of behavior, responding on the target key either remained unchanged or decreased, but was not eliminated. Responding on the target key was not maintained in the absence of an intermittent schedule of food presentation.

Aggression↗
PubMed1970

Schedule-induced aggression as a function of fixed-ratio value.

Pigeons responding for food on fixed-ratio reinforcement schedules attacked live target birds when the ratio value was increased, but not when the value was decreased. The frequency of attacks peaked several days after ratio value change, and then gradually decreased to an original level.

Aggression↗
PubMedDate not supplied

Drug excretion in human breast milk: principles, pharmacokinetics and projected consequences.

The excretion of drugs in human breast milk is reviewed with regard to milk production, composition, feeding patterns and mechanisms of drug transfer into milk. Fundamental principles of breast milk excretion are used to construct a pharmacokinetic approach useful for the study of most drugs. An infant-modulated 3-compartment open model is proposed for drug distribution and elimination in the breast feeding woman. Milk/plasma drug concentration ratios are projected on the basis of pH partitioning. While some studies confirm these projections, other studies demonstrate a need to consider additional factors such as lipid solubility and protein binding characteristics of a drug in milk. Data are lacking for most drugs and hence dosing via milk or risk to the infant remains speculative. Very few pharmacokinetic studies of both milk and infant plasma were found. A review of selected drug classes cites available information as a basis for future studies. Few drugs are contraindicated in breast feeding women, but supportive data for either proscriptions or permissive statements are often lacking. A neglected but potentially serious infant risk--impaired behaviour and development--is discussed from the standpoint of emerging animal data. Conceptually valid and comprehensive studies on drug excretion in breast milk are needed if this valuable nutrient for infants is to be made available safely.

Absorption↗