ABSTRACT
OBJECTIVE: Recently, the serotonin-dopamine interaction is being regarded as a possible mechanism for both less extrapyramidal symptoms and good therapeutic effect on negative symptoms which are outstanding advantages of atypical antipsychotics. The goal of the study was to further define serotonin dopamine interaction in three different brain area of rats ; prefrontal cortex, striatum and nucleus accumbens. METHOD: The rats used in this study weighed 150-300gm. Under the aesthesia with pentothal sodium(25 mg/kg), stainless steel cannula was inserted in the right substantia nigra according to atlas(Paxinous and Watson) and 6-OHDA was injected at the rate of 1 mul/min to make a unilateral substantia nigra lesion. A week later, apomorphine (s. c. 0.1 mg/kg) was injected through the cannula and the rats with circling behavior counting more than 200 for an hour were selected for the study. Three weeks after that, the rats were further divided into 3 groups according to the brain area that permanent stainless steel cannula was implanted : prefrontal cortex group, striatum group and nucleus accumbens group. Within each group comparison was done between the number of circling behavior obtained by the injection of vehicle plus apomorphine and the one obtained by the injection of ritanserin plus apomorphine. Wilcoxon signed ranks test was used in data-analysis. RESULTS: The effect of ritanserin on the circling behavior in prefrontal cortex was absent but in striatum and nucleus accumbens, increasing effect was noted. CONCLUSIONS: It might be suggested that serotonin has an inhibitory control on dopaminergic function in striatum and nucleus accumbens.
Subject(s)
Animals , Rats , Antipsychotic Agents , Apomorphine , Brain , Catheters , Dopamine , Nucleus Accumbens , Oxidopamine , Prefrontal Cortex , Ritanserin , Serotonin , Stainless Steel , Substantia Nigra , ThiopentalABSTRACT
OBJECTIVES & METHODS: To compare a drinking culture between Korean and Chinese University students, an appropriate questionnaire was developed and surveyed to 244 Korean students and 220 Chinese students with a co-administration of NAST to rule out problem drinkers from November 1997 to April 1998. RESULTS: 1) The numbers of problem drinker detected by NAST were 39 for Korean students and 20 for Chinese students. They were all excluded in the analysis. 2) Drinking rate for Korean students was 94.1% , much higher than that of Chinese, 62.6% and drinking frequency was also higher in Koreans The most preferred alcoholic liquor was beer for both countries and the most preferred place for drinking was beer house for Korean and home for Chinese. SuJack(passing one's own glass to other people) was also found to be practiced among small percentage of Chinese students, 18.7%. 3) As for the drinking motivations, emotional one and expectation for the alcoholic effect itself were negative for both countries. However, social one was strong for Koreans and neutral for Chinese. 4) As for the drinking behaviors, both countries showed autonomous and abstinent behavior: drinking manner and group solidarity were counted more importantly by Koreans while objectives of drinking was considered more importantly by Chinese. 5) As for the drinking perceptions, both countries showed a negative attitude toward admiration of alcoholic usefulness but positive attitude toward the need for social regulation of alcohol and generosity toward a drunken behavior. CONCLUSIONS: These results show that drinking culture of Korean and Chinese University students is the same in terms of autonomous and abstinent behavior but quite different in terms of certain other drinking behavior and perception which might be related to their economical and cultural differences.
Subject(s)
Humans , Alcoholics , Asian People , Beer , Drinking Behavior , Drinking , Glass , Surveys and QuestionnairesABSTRACT
Tardive dyskinesia(TD) is a serious side effect of long-term treatment with neuroleptic medications. To investigate if glutamatergic hyperfunction is associated with TD, effect of MK-801 on the prevention and treatment of TD was studied using a rat model, i.e., vacuous chewing movements(VCM). When comparing VCM scores of Group I(haldol decanoate+MK-801) with that of Group II(hadol decanoate+phosphate buffer saline), late measured VCM scores of former were significantly lower than that of latter, meaning that MK-801 is effective in the prevention of VCM. Furthermore, when MK-801 is also effective in the treatment of VCM. From the above results, it is suggested that glutamatergic hyperfunction might be involved in the development of TD and MK801 could be effective in the prevention and treatment of it.
Subject(s)
Dizocilpine Maleate , Mastication , Models, Animal , Movement DisordersABSTRACT
The aim of this study was to examine the effects of various concentrations of glutamate(10(-8), 10(-6) and 10(-4) M) on the circling movement induced by apomorphine in the unilateral substantia nigra-lesioned rats. Subcutaneous apomorphine(0.1 mg/kg) elicited contralateral circling movement(641.7+/-163.9/hr), Glutamate(10(-6)-10(-4) M) significantly reduced the numbers of apomorphine-induced circling movement. This reducing effect of glutamate was antagonized and/or reversed by 10(-7) M GABA antagonist bicuculline. These results suggest that glutamate reduces circling movement induced by apomorphine and this reducing effect of glutamate may be mediated by increased GABA concentration in striatum and substantia nigra.