Observations on the hypothermic effect of metrazol in the conscious cat

In the unanesthetized cat maintained at an ambient temperature of 22–24°C, metrazol injected intraperitoneally in doses from 60–90 mg/kg first caused restlessness followed by autonomic changes and tonic-clonic convulsions. During these convulsions a simultaneous rise in temperature of 0.3–0.5°C occurred that lasted for about 90 min. Thereafter, a long-lasting hypothermia of about 6 hr duration developed. Within 24 hr the temperature returned to its normal level. Pretreatment with an intraperitoneal injection of phenobarbital sodium (50.0–150.0 mg/kg) 30 min prior to metrazol prevented the long-lasting fall in temperature, as well as the autonomic phenomena and tonic-clonic convulsions. The initial transient hyperthermia was not observed when the temperature was lowered by prior treatment with phenobarbital. The hypothermic effect of metrazol is probably the consequence of its direct action on thermoregulatory centers in the hypothalamus.     

PERCEPTUAL, MOTOR AND ATTENTIONAL DEFICITS IN SEVEN-YEAR-OLD CHILDREN

ABSTRACT. 42 children representative of Swedish urban seven-year-olds with a combination of various minor neurodevelopmental deficits in the form of so-called minimal brain dysfunction (MBD) syndromes were compared with 51 children of the same age without such problems as regards general health data from parents'interviews and questionnaires and from paediatric examinations. The findings at the physical examination revealed only few and small differences concerning minor physical anomalies that, in part, is dealt with in a separate report. Children with MBD had experienced simple febrile convulsions significantly more often than controls, and an abnormal EEG was a common finding in these cases. So-called psychosomatic complaints were not overrepresented in the MBD group, but enuresis and encopresis was somewhat more common. The parents'answers to a set of 6 questions (concerned with late speech development, late motor development, gross motor clumsiness, fine motor clumsiness, "shuffling" and difficulties to concentrate) were found to have a high discriminating capacity detecting for MBD syndromes. The possibility of a clinical application of this finding is discussed.     

Pentylenetetrazol kindling in rats: Is neurodegeneration associated with manifestations of convulsive activity?

Structural changes in neurons and measures of oxidative stress were studied in the hippocampus of rats tolerant (ST) and sensitive (SS) to developing clonic-tonic seizures in conditions of pentylenetetrazol kindling. Sequences of 11 injections of pentylenetetrazol significantly decreased the number of normal neurons in hippocampal field CA1 in SS rats, this effect being seen in both hippocampal field CA1 and the dentate fascia in ST rats. Decreases in the numbers of normal neurons were accompanied by increases in the numbers of damaged cells in field CA4 in rats of both groups. After 21 injections, decreases in the numbers of normal neurons were seen in field CA1 in both SS and ST rats, while the numbers of damaged neurons were significantly greater than control only in ST rats in fields CA1 and CA4. The glutathione level was significantly lower in the hippocampus in both groups of rats than in controls. Thus, rats “ tolerant” to developing convulsions show signs of oxidative stress and neurodegenerative changes in the hippocampus. This suggests that oxidative neuron damage leading to neurodegeneration in the pentylenetetrazol kindling model is not directly associated with convulsive activity. __________ Translated from Rossiiskii Fiziologicheskii Zhurnal imeni I. M. Sechenova, Vol. 91, No. 7, pp. 764–775, July, 2005.     

新生儿惊厥56例临床分析

目的:分析新生儿惊厥相关病因,为有效地预防新生儿惊厥的发生提供依据。方法:回顾性分析56例新生儿惊厥的临床资料,分析不同日龄新生儿惊厥的病因、惊厥发作形式以及相关的实验室和影像学检查结果。结果:由围产因素导致的缺氧缺血性脑病(HIE)和颅内出血(ICH)为新生儿惊厥的主要原因,其中HIE 31例(55.36%),ICH 8例(14.29%);其次为低钙血症和感染因素,各6例(10.71%)。3 d内发病占大多数,为69.64%。结论:多种病因可导致新生儿惊厥,以围产期因素最多见;而微小型发作是新生儿惊厥的主要表现形式,且易被临床忽略。应建立完善的围生期保健制度,加强高危新生儿监护,提高产科技术,有助于降低发病率、后遗症及死亡率。     

Investigation of the anticonvulsive effect of acute immobilization stress in anxious Balb/cByJ mice using GABAA-related mechanistic probes

Rationale A disordered regulation of neuroactive steroids release in response to acute stress could induce GABAergic dysfunctions underlying anxiety disorders. Objectives First, we conducted studies indicating that a short immobilization stress in anxious Balb/cByJ mice produced an anticonvulsive effect. Second, the effects of different positive allosteric modulators (etifoxine, progesterone, clonazepam, and allopregnanolone) of GABA_A receptors were compared in a mouse model mimicking the disruption of the acute stress-induced neuroactive steroids release with finasteride (types I and II 5α-reductase inhibitor). Results The acute stress-induced anticonvulsive effect, expressed by the threshold dose of t-butylbicyclophosphorothionate-producing clonic seizures, was time-dependent. The extent of the enhancement of acute stress-induced anticonvulsive effect was lowered in the presence of finasteride. The same effect was observed with PK11195, which behaves as an antagonist of the peripheral benzodiazepine receptor in the dose range used in this study. Picrotoxin reduced the acute stress anticonvulsive effect, proving that this effect operates through the GABA_A receptor. Contrary to progesterone (up to 30 mg/kg), etifoxine (50 mg/kg), allopregnanolone (10 mg/kg), and clonazepam (10 μg/kg) inhibited the finasteride effect in stressed animals. The effect of etifoxine was blocked in the presence of finasteride and picrotoxin combined in stressed animals. Conclusions These findings support the hypothesis suggesting an involvement of neuroactive steroids in the anticonvulsive effect of restraint stress. The dual and complementary mechanisms of action of etifoxine (directly on the GABA_A receptor and indirectly via the neuroactive steroids) may represent a therapeutic benefit in the treatment of various anxiety disorders with abnormal production of neuroactive steroids.     

Risk Factors for a First Febrile Convulsion in Children: A Population Study in Southern Taiwan

PURPOSE: To identify risk factors for a first febrile convulsion among 3-year-old children by a matched case-control population study. METHODS: All 11,714 neonatal survivors born in Tainan City between October 1989 and September 1991 were enrolled. At age 3, 10,460 children were available for telephone survey for febrile convulsions, and were confirmed by home visit interviews. Those without history of seizure were randomly matched to each febrile convulsion case by age, gender, and residence district. RESULTS: Two hundred fifty six children had febrile convulsions, and 218 of them and their matched controls were available for analysis. The febrile convulsion cases had significantly more febrile episodes (four or more) per year (33.0 vs. 22.5%; p = 0.021), and cases had a higher percentage of developmental delay (3.7 vs. 0.4%; p = 0.046) and a higher percentage of febrile convulsions in their siblings (12 vs. 0.4%; p = 0.011) than controls. The other sociodemographic, environmental, and biologic variables showed no differences between cases and controls. Step-wise logistic regression showed a highly significant independent association between febrile convulsions and history of febrile convulsions in the siblings, and a moderate one between febrile convulsions and the number of febrile episodes per year. CONCLUSIONS: The presence of febrile convulsions in the siblings and the number of fever episodes per year were the independent and significant predictors of febrile convulsion for an individual case in our population-based sample.     

大鼠氧惊厥时脑内μ-阿片受体的变化

目的　探讨大鼠氧惊厥时脑内 μ-阿片受体的变化。方法　用 [3H]-羟甲芬太尼作为特异性标记配体 ,采用放射配体受体结合实验 (radioligand binding assay,RBA) ,测定在几种不同气体及压力的暴露条件下 ,大鼠脑内 μ-阿片受体的 k D值和 Bmax值的变化。结果　大鼠氧惊厥前 ,脑内 μ-阿片受体的 k D值即有增大趋势 (但 P>0 .0 5 ) ,Bmax值减小 (P<0 .0 1) ;氧惊厥时 k D值进一步升高 (P<0 .0 1) ,Bmax值反而增大 (P<0 .0 1)。结论　结果提示 :(1)氧惊厥发作中 ,μ-阿片受体的数量增多 ,而其结合活性降低。(2 )在高压氧 (HBO)暴露中 ,μ-阿片受体参与了氧惊厥的过程     

Hereditary febrile seizures: Phenotype and evidence for a chromosome 19p locus

The occurrence of febrile seizures (FSs) in large autosomal dominant FS kindreds makes possible accurate delineation of the pure clinical phenotype of hereditary FS among secondary FS cases, and the identification of gene loci causing susceptibility to FS. Recently FS gene loci on chromosomes 8 and 19 were identified. We studied the phenotype of FS in four large families in which FS is an autosomal dominant trait. Among 30 affected secondary FS cases, mean age of onset was 16.3 months (range 4 to 36 months), sex ratio was equal, and 43% were complex (13 of 30). Among these 30 secondary FS cases, the mean number of FSs was 2.1, half had only a single FS, and none had afebrile seizures. Penetrance was 0.67, approximately the same as in our previous larger group of 40 multicase FS families (0.64). The occurrence of DPT encephalopathy in a sib of a patient with FS raises the possibility that these two etiologies are related. Linkage studies showed that one of the four families (Family 1) was linked to chromosome 19p markers, none of the families was linked to chromosome 8q markers, and the largest FS family (Kindred 6) was unlinked to either 19p or 8q markers, supporting the hypothesis of genetic heterogeneity for FS. Am. J. Med. Genet. 79:354–361, 1998. © 1998 Wiley-Liss, Inc.     

苯巴比妥联合地西泮治疗急诊小儿惊厥的效果观察

目的 观察苯巴比妥联合地西泮治疗急诊小儿惊厥的临床效果.方法 94例惊厥患儿,采用随机数字表法分为对照组和研究组,各47例.对照组给予地西泮治疗,研究组给予苯巴比妥联合地西泮治疗.比较两组患儿临床疗效、惊厥症状控制时间、实验室相关指标及复发率.结果 研究组总有效率95.74％高于对照组的72.34％,差异有统计学意义(...