Objective A morphometric study was carried out on GABAergic neurons and astrocytes in primary auditory cortex of 4 young cats (1-3 years old, 20-2.5 kg) and 4 old cats (10-13-year-old, 3-3.5 kg), in order to explore the age-related changes and the probably physical effects underlying these changes. Methods The same regions of the primary auditory cortex (AI) were comparatively studied. Nissl staining and immunohistochemical methods were applied to explore the differences of GABAergic neurons and astrocytes(specifically labeled by GFAP as a mark as antibody) in the primary auditory cortex(Al) between young and old cats. Serial cross-sections from two age groups were stained with Nissl for layer structure observation and demonstration of neurons; Adjacent sections were stained with anti_GABA immunohistochemistry for localizing and characterizing GABAergic and with anti-GFAP for astrocytes in AI. Results The diameter, density and number of GABAergic neurons in Al of old cats declined significantly compared with the counterpart in young cats, especially in layers Ⅱ,Ⅲ of AI; but the change in GFAP-IR cells was reversed: old cats showed clearly larger number and stronger staining of GFAP-IR cells than that in young cats. The GFAP-IR cell bodies and dendrites swelled obviously in old cats, especially in layer Ⅰ of AI and in white matter. Conclusion The result presented a direct morphological evidence for weakness of GABAergic intracortical inhibition, which is considered to be a possible mechanism for age-related acoustic function decline. The enhanced function of astrocytes may play an important role in decreasing the GABA content in AI of the old individuals.

To explore the relationship between the drug-seeking behavior, motivation of conditioned place preference (CPP) rats and the frontal association cortex (FrA) electroencephalogram (EEG) sample entropy, we in this paper present our studies on the FrA EEG sample entropy of control group rats and CPP group rats, respectively. We invested different behavior in four situations of the rat activities, i. e. rats were staying in black chamber of videoed boxes, those staying in white chamber of videoed boxes, those shuttling between black-white chambers and those shuttling between white-black chambers. The experimental results showed that, compared with the control group rats, the FrA EEG sample entropy of CPP rats staying in black chamber of video box and shuttling between white-black chambers had no significant difference. However, sample entropy is significantly smaller (P < 0.01) when heroin-induced group rats stayed in white chamber of video box and shuttled between black-white chambers. Consequently, the drug-seeking behavior and motivation of CPP rats correlated closely with the EEG sample entropy changes.
Animals ; Conditioning (Psychology) ; drug effects ; Drug-Seeking Behavior ; Electroencephalography ; Entropy ; Frontal Lobe ; drug effects ; physiology ; Heroin ; pharmacology ; Rats ; Rats, Sprague-Dawley

Teaching anesthesia-physiology is a subject worth to be discussed.Arranging the high quality teachers to teach,making a careful study and preparation of the teaching materials,teaching plan and enhancing the teachers’teaching art should be first emphasized.And then the advantages of using multimedia should be given full play in combination with various kinds of methods to let the students become active class participants so as to improve the teaching effect in anesthesia-physiology.

OBJECTIVE: To analyze the relationship between the electroencephalograph (EEG) changes of temporal association cortex (TeA) and the drug-seeking behavior in heroin-induced conditioned place preference (CPP) rats. METHODS: The rats were randomly divided into an operated control group and a heroin-induced CPP group after the electrodes were buried in TeA by stereotactic technology. The TeA EEG was recorded by the CPP video system combining with the EEG wireless telemetry, where the rats stayed in black or white chambers, shuttling from black to white chambers or from white to black chambers. RESULTS: Compared with the operated control group, the percentage of TeA θ waves was increased significantly when staying in black or white chambers in the heroin-induced CPP group (P<0.05, P<0.01). Compared with the operated control group, when rats shuttling between the 2 chambers, the TeA δ waves were reduced (P<0.01), but β waves, β2 waves in particular, were increased (P<0.01) in the heroin-induced CPP group (P<0.05, P<0.01). Compared with staying in the black chamber, when heroin-induced CPP rats were shuttling between black and white chambers, the right TeA θ waves were reduced, and β waves, β2 waves in particular, were increased (P<0.01). Compared staying in the white chamber with shuttling between white and black chambers in the heroin induced CPP rats, the right TeA θ waves, but not β waves, were reduced (P<0.01). CONCLUSION The EGG changes on the right TeA in the heroin-induced CPP rats, including the increased fast waves (β, β2) and the reduced slow wave (θ), may be related to drug-seeking behaviors.
Animals ; Conditioning, Psychological ; drug effects ; Drug-Seeking Behavior ; Electroencephalography ; Heroin ; Rats ; Telemetry ; Temporal Lobe ; drug effects

OBJECTIVETo investigate the changes of telemetry electrical activity in the infralimbic cortex (IL) of morphine-dependent rats with extinguished drug-seeking behavior.

METHODSSD rats were randomly divided into model group and control group and received operations of brain stereotaxic electrode embedding in the IL. The rats in the model group were induced to acquire morphine dependence and then received subsequent extinction training, and the changes of electrical activity in the IL were recorded with a physical wireless telemetry system.

RESULTSIn rats with morphine dependence, the time staying in the white box was significantly longer on days 1 and 2 after withdrawal than that before morphine injection and that of the control rats, but was obviously reduced on days 1 and 2 after extinction training to the control level. Compared with the control group, the morphine-dependent rats on day 2 following withdrawal showed significantly increased β wave and decreased δ wave when they stayed in the white box but significantly increased δ wave and decreased α wave and β wave when they shuttled from the black to the white box. On day 2 of extinction, the model rats, when staying in the white box, showed significantly decreased θ wave compared with that of the control rats group but decreased β wave and θ wave and increased δ wave compared with those in the withdrawal period. When they shuttled from black to white box, the model rats showed decreased δ wave and increased α wave and β wave compared with those in the withdrawal period.

CONCLUSIONMorphine-dependent rats have abnormal changes of electrical activity in the IL in drug-seeking extinction to affect their drug-seeking motive and inhibit the expression and maintenance of drug-seeking behaviors.

Animals ; Cerebral Cortex ; drug effects ; physiology ; Drug-Seeking Behavior ; physiology ; Electrophysiological Phenomena ; Extinction, Psychological ; Morphine ; pharmacology ; Morphine Dependence ; physiopathology ; Rats ; Rats, Sprague-Dawley ; Telemetry