Subject(s)
Education, Graduate , Neurosciences/education , Data Collection , Demography , Education, Graduate/economics , Education, Graduate/trends , Employment/economics , Employment/trends , Humans , National Academy of Sciences, U.S. , National Institutes of Health (U.S.) , Neurosciences/economics , Neurosciences/trends , Societies, Scientific , Specialization/economics , Specialization/trends , Students , Time Factors , Training Support , United States , WorkforceABSTRACT
Intraperitoneal injection of FK 33-824 produced apomorphine-like stereotyped behavior in rats. Antagonism of this stereotypy by naloxone and neuroleptics suggests that FK 33-824 can activate opiate and dopamine receptors in the brain. Because increased dopaminergic neuronal activity is thought to be involved in schizophrenia and dopamine-mediated stereotypy has been used as an animal model for this illness, these results are consistent with an involvement of endogenous opiate-like peptides in schizophrenia. This involvement provides a possible mechanism for the reported improvement in schizophrenic psychosis produced by naloxone.
Subject(s)
Dopamine/physiology , Endorphins/pharmacology , Enkephalins/pharmacology , Stereotyped Behavior/drug effects , Animals , Apomorphine/pharmacology , Chlorpromazine/pharmacology , D-Ala(2),MePhe(4),Met(0)-ol-enkephalin , Dose-Response Relationship, Drug , Haloperidol/pharmacology , Humans , Male , Naloxone/pharmacology , Rats , Receptors, Dopamine/drug effects , Receptors, Opioid/drug effectsABSTRACT
At a dose as low as 1 microgram per kilogram of body weight, lysergic acid diethylamide (LSD) significantly decreased the suppressive effect of electric shock on licking behavior of the rat. Attenuation of punishment was also obtained with mescaline, but neither dimethyltryptamine nor delta9-tetrahydrocannabinol was active in this test. Cyproheptadine and alpha-propyldopacetamide, drugs that interfere with the function of neurons that contain serotonin, have a behavioral effect similar to that of LSD and mescaline, which suggests that the attenuation of punishment produced by these hallucinogens may result from decreased activity of such neurons.
Subject(s)
Behavior, Animal/drug effects , Lysergic Acid Diethylamide/pharmacology , Mescaline/pharmacology , Punishment , Amides/pharmacology , Animals , Behavior, Animal/physiology , Brain Stem/drug effects , Clomipramine/pharmacology , Cyproheptadine/pharmacology , Dronabinol/pharmacology , Electroshock , Male , N,N-Dimethyltryptamine/pharmacology , Neurons/drug effects , Rats , Receptors, Drug/drug effects , Serotonin/physiologyABSTRACT
N-n-propylnorapomorphine (NPA) is 35 times more potent than apomorphine (APO) in producing stereotyped behavior in rats. The effect of NPA is blocked by perphenazine but unaltered by alpha-methyltyrosine pretreatment and is accompanied by a decrease in central dopamine turnover. The activity of APO and NPA appears to be primarily in the (-)-isomer, and is diminished but not lost by removal of either hydroxyl group from the catechol ring system.
Subject(s)
Apomorphine/analogs & derivatives , Behavior/drug effects , Stereotyped Behavior/drug effects , Animals , Apomorphine/antagonists & inhibitors , Apomorphine/pharmacology , Catecholamines/metabolism , Dopamine/metabolism , Humans , Isomerism , Male , Methyltyrosines/pharmacology , Norepinephrine/metabolism , Perphenazine/pharmacology , Rats , StereoisomerismSubject(s)
Dihydroxyphenylalanine/pharmacology , Hydroxydopamines/pharmacology , Motor Activity/drug effects , Amines/metabolism , Animals , Brain/metabolism , Cerebral Cortex/metabolism , Corpus Striatum/metabolism , Dihydroxyphenylalanine/metabolism , Dopamine/metabolism , Dose-Response Relationship, Drug , Drug Synergism , Hypothalamus/metabolism , In Vitro Techniques , Male , Mesencephalon/metabolism , Norepinephrine/metabolism , Pharmaceutical Vehicles/pharmacology , Rats , Time Factors , TritiumSubject(s)
Catecholamines/physiology , Conditioning, Operant/drug effects , Hydroxydopamines/pharmacology , Animals , Brain Chemistry/drug effects , Chromatography, Ion Exchange , Dopamine/analysis , Fluorometry , Male , Methyltyrosines/pharmacology , Neurons/physiology , Norepinephrine/analysis , Osmolar Concentration , Rats , Reinforcement Schedule , Time Factors , Water DeprivationSubject(s)
Dihydroxyphenylalanine/pharmacology , Dopamine/pharmacology , Motor Activity/drug effects , Animals , Brain Chemistry/drug effects , Cerebral Ventricles , Chromatography, Ion Exchange , Dihydroxyphenylalanine/administration & dosage , Dopamine/analysis , Drug Synergism , Injections , Male , Norepinephrine/analysis , Rats , Serotonin/analysisABSTRACT
Intramuscular injections of melatonin had a dose-dependent, rate-increasing effect on responding maintained by a fixed-interval schedule of positive reinforcement. When a punishment contingency was added to the fixed-interval schedule, the overall rates were not increased although responding was increased during the initial part of each interval.