Daniela Osteicoechea | The University of Texas at Austin (original) (raw)
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Papers by Daniela Osteicoechea
Psychopharmacology, Jan 22, 2018
Pain is the leading reason for seeking health care, and mu opioid receptor agonists continue to b... more Pain is the leading reason for seeking health care, and mu opioid receptor agonists continue to be prescribed despite well-documented adverse effects. Kappa opioid receptor agonists have antinociceptive effects with little to no abuse liability and might be useful for treating pain in mixtures. Kappa:mu opioid mixtures might be useful if therapeutic effects of each drug can be selectively increased while reducing or avoiding the adverse effects that occur with larger doses of each drug alone. This study characterized the effects of the kappa opioid receptor agonist spiradoline alone (0.32-56 mg/kg) and in 1:10, 1:3, 1:1, and 3:1 mixtures with the mu opioid receptor agonists morphine (1.0-32 mg/kg) and etorphine (1-10 μg/kg) on warm water tail-withdrawal latency, body temperature, responding for food, and fecal output in male Sprague-Dawley rats (n = 24). Antinociceptive effects were greater than additive for 1:10 and 1:3 spiradoline:morphine mixtures and for 1:10, 1:3, and 1:1 spira...
Behavioural Pharmacology, 2018
Intravenous (i.v.) drug self-administration remains the "gold standard" for assessing abuse poten... more Intravenous (i.v.) drug self-administration remains the "gold standard" for assessing abuse potential of drugs. Failure of a drug to maintain self-administration might indicate merely the absence of positive reinforcing effects but might also indicate presence of aversive effects. Sensitivity to aversive effects is thought to affect the initiation and maintenance of drug use as well as relapse. Choice procedures are used to study positive reinforcing effects of drugs and to a much lesser extent to study punishing effects of drugs. Experiment 1 compared the mu opioid receptor agonist remifentanil (0.001-0.01 mg/kg/infusion), the kappa receptor agonist spiradoline (0.0056-0.056 mg/kg/infusion), and histamine (1.0 mg/kg/infusion) in rats choosing between a food pellet only and an intravenous (i.v.) infusion + a food pellet. To test whether a history with one punishing drug affects the punishing effects of a second drug, Experiment 2 compared sensitivity to spiradoline in rats with and without a history of histamine punishment. All rats predominantly chose a pellet alone when histamine + a pellet was the alternative, and they predominantly chose remifentanil + a pellet over a pellet alone. In Experiment 2, spiradoline was punishing in rats with a history of histamine punishment but not drug-naïve rats. This food choice procedure is sensitive to reinforcing and punishing effects of different drugs in the same subjects, suggesting that the procedure is well-suited for studying drug mixtures (e.g., mu and kappa agonists) and the impact of different physiological conditions (e.g., pain) on reinforcement and punishment.
Psychopharmacology, Jan 22, 2018
Pain is the leading reason for seeking health care, and mu opioid receptor agonists continue to b... more Pain is the leading reason for seeking health care, and mu opioid receptor agonists continue to be prescribed despite well-documented adverse effects. Kappa opioid receptor agonists have antinociceptive effects with little to no abuse liability and might be useful for treating pain in mixtures. Kappa:mu opioid mixtures might be useful if therapeutic effects of each drug can be selectively increased while reducing or avoiding the adverse effects that occur with larger doses of each drug alone. This study characterized the effects of the kappa opioid receptor agonist spiradoline alone (0.32-56 mg/kg) and in 1:10, 1:3, 1:1, and 3:1 mixtures with the mu opioid receptor agonists morphine (1.0-32 mg/kg) and etorphine (1-10 μg/kg) on warm water tail-withdrawal latency, body temperature, responding for food, and fecal output in male Sprague-Dawley rats (n = 24). Antinociceptive effects were greater than additive for 1:10 and 1:3 spiradoline:morphine mixtures and for 1:10, 1:3, and 1:1 spira...
Behavioural Pharmacology, 2018
Intravenous (i.v.) drug self-administration remains the "gold standard" for assessing abuse poten... more Intravenous (i.v.) drug self-administration remains the "gold standard" for assessing abuse potential of drugs. Failure of a drug to maintain self-administration might indicate merely the absence of positive reinforcing effects but might also indicate presence of aversive effects. Sensitivity to aversive effects is thought to affect the initiation and maintenance of drug use as well as relapse. Choice procedures are used to study positive reinforcing effects of drugs and to a much lesser extent to study punishing effects of drugs. Experiment 1 compared the mu opioid receptor agonist remifentanil (0.001-0.01 mg/kg/infusion), the kappa receptor agonist spiradoline (0.0056-0.056 mg/kg/infusion), and histamine (1.0 mg/kg/infusion) in rats choosing between a food pellet only and an intravenous (i.v.) infusion + a food pellet. To test whether a history with one punishing drug affects the punishing effects of a second drug, Experiment 2 compared sensitivity to spiradoline in rats with and without a history of histamine punishment. All rats predominantly chose a pellet alone when histamine + a pellet was the alternative, and they predominantly chose remifentanil + a pellet over a pellet alone. In Experiment 2, spiradoline was punishing in rats with a history of histamine punishment but not drug-naïve rats. This food choice procedure is sensitive to reinforcing and punishing effects of different drugs in the same subjects, suggesting that the procedure is well-suited for studying drug mixtures (e.g., mu and kappa agonists) and the impact of different physiological conditions (e.g., pain) on reinforcement and punishment.