Organization and expression of agonistic and socio-sexual behavior in golden hamsters over the estrous cycle and after ovariectomy

Paris of hamsters were housed in large enclosures that contained separate male and female living areas and observed over the 4-day estrous cycle and after ovariectomy. Agonistic elements exhibited frequently by females included on-back, boxing, lateral posturing, and biting, whereas males engaged frequently in boxing and on-back patterns of behavior. Furthermore, on-back and boxing by females were significantly higher on estrus than on any other day of the estrous cycle. Agonistic acts performed after ovariectomy did not differ in occurrence from those shown by animals on diestrus and proestrus. Vaginal marking increased during diestrus and attained a peak 24 hr prior to sexual receptivity. Both vaginal marking and mating occurred more frequently in the female's than male's home area suggesting that vaginal marks on days preceding behavioral estrus serve to attract males to the nest of females. Males also organized their marking patterns by location as shown by more flank marking in their own than their partner's area, albeit the significance for this difference in location is not known. The results demonstrate that when heterosexual paris of hamsters are tested in large and partially familiar habitats, a wide range of behavior is exhibited and organized in a manner that is not observed in small and unfamiliar cages.     

帕金森病模型大鼠中脑腹侧被盖区多巴胺能神经元改变的实验研究

目的：探讨帕金森病（Parkinson’s disease，PD）大鼠模型中脑腹侧被盖区（ventral tegmentalarea，VTA）多巴胺能神经元的改变。方法：应用6-羟基多巴胺（6-hydroxydopamine，6-OHDA）注射右侧黑质致密区（substantia nigra compacta，SNc）制作PD大鼠模型，进行阿朴吗啡（apomorphine，APO）诱发行为学观察、电镜、尼氏染色观察中脑VTA神经元的改变、酪氨酸羟化酶（tyrosine hydroxylase，TH）免疫组织化学ABC观察其DA能神经元的改变并进行图像分析。结果：APO诱发PD大鼠模型异常旋转行为，尼氏染色见PD大鼠中脑VTA有神经细胞肿胀、坏死等变化，VTA TH阳性神经元数量减少，形态学改变。结论：中脑VTA DA能神经参与PD模型大鼠的改变；APO能诱导6-OHDAPD模型大鼠的旋转行为，其强弱可能与TH^＋神经元数量直接相关。     

Changes in myocardial capillary diffusion capacity during infusion of vasoactive drugs

The present study investigated how variations in coronary vascular resistance and metabolic demand affected myocardial capillary diffusion capacity. Hearts from Wistar rats were perfused with Krebs-Henseleit-albumin buffer in a Langendorff preparation, where heart rate (HR), contractility (dP/dt_max) and myocardial oxygen consumption (MVO₂) were recorded continuously. Myocardial capillary diffusion capacity was measured as the permeability surface area product (PS) for Cr-EDTA and vitamin B₁₂ by the single injection colorimetric indicator dilution method. After base-line recordings without drugs, angiotensin II + arginine-vasopressin was infused, which increased coronary vascular resistance by 90%, stimulated HR by 11%, decreased dP/dt_max by 21% and reduced MVO₂ by 4%. PS_Cr-EDTA and PS_B12, decreased by 24 and 27%, respectively, leaving the ratio PS_Cr-EDTA/PS_B12 unchanged indicating unaltered capillary permeability. Moreover, the reductions in MVO₂ and PS correlated significantly. During vasodilation: (1) nitroprusside-NA stimulated HR by 7% and decreased dP/dt_max by 14%; (2) adenosine reduced dP/dt_max by 37% and decreased MVO₂ by 9%; and (3) isoproterenol increased HR, dP/dt_max and MVO₂ by 53, 76 and 9%, respectively. However, all three vasodilators reduced PS_Cr-EDTA and PS_B12 in parallel by 7–25% leaving PS_Cr-EDTA/PS_B12 unchanged. Thus, maximal estimated diffusion capacities were obtained during spontaneous coronary vascular tone, most likely reflecting maximal capillary recruitment in the Krebs-Henseleit-albumin perfused heart. The derecruiting effects of the vasoconstrictors were partly overridden by metabolic factors, while the reductions of PS after vasodilation more likely were due to increased heterogeneity in coronary flow.     

Epidemiologic survey and genetic analysis of endemic hepatitis C virus infection in a Japanese town with a high prevalence of hepatitis B virus carriers

Mass screening for hepatitis C virus antibody was carried out in 875 inhabitants (313 men and 562 women) of a town in Japan with a high rate of hepatitis B virus infection. The overall rate of positivity for anti-HCV was 8.8% (6.4% in men and 10,1% in women). The rate of positivity for hepatitis B virus surface antigen was 11.2%. Five subjects (0.6%) were positive for both markers. HCV-RNA was detected in 65 (88.4%) of 77 individuals who were positive for anti-HCV and in 1 (1.5%) of 60 individuals negative for anti-HCV. The genotype of the HCV genome was determined by PCR analysis using type-specific primers in 60 individuals. HCV type 1b was detected in 51 subjects (85%), type 2a in 3 subjects (5%), and type 2b in 6 subjects (10%). None of the individuals was infected with more than one genotype. The nucleotide sequences of the partial nonstructural 5 region of HCV type 1b genotype obtained from 6 individuals showed at least 92.0% homology in the nucleotide sequence, and 94.8% homology in the amino acid sequence. Homology among these clones was greater than their homology with previously described type 1 b sequences. The findings suggest that there was a specific local origin of HCV infection, although it was not possible to identify any single source of HCV infection. The results also indicate the presence of asymptomatic HCV carriers. © 1995 Wiley-Liss, Inc.     

Acute thermoregulatory effects of unilateral electrolytic lesions of the medial and lateral preoptic area in rats

Unilateral anodal lesions of the medial or lateral preoptic area (POA) in unanesthetized rats had opposite thermoregulatory effects immediately after the lesions were made. Lesions of the medial POA evoked hyperthermias and accompanying cold defense responses, including vasoconstriction of the tail, increased oxygen consumption, shivering, and heat conservation postures. The hyperthermias had latencies of 0–30 minutes and reached maximum values within 120 minutes postlesion. They were independent of ambient temperature and dissociable from the hyperactivity often seen after such lesions. Damage to the lateroventral POA elicited acute falls in body temperature, as well as vasodilation of the tail, decreased oxygen consumption, inhibition of shivering in cool environments, and prone body extension. Unilateral cathodal lesions throughout the POA yielded only hyperthermia. These results suggest a possible anatomical segregation of heat and cold defense functions within the anterior basal forebrain.     

肱骨头两维平面激光投影测量

本文报道用激光对100例成人肱骨头进行两维平面测量,即正位、侧位、左、右45°斜位肱骨头的半径、关节面高度、张角及表面面积等。其结果为:1.肱骨头关节面的张角平均为144.48±11.93°。2.肱骨头半径及高度分别为2.15±0.16 cm、1.56±0.24 cm。肱骨头关节面高度占近似球体直径的36.05％。3.肱骨头关节面的表面积为21.02±4.03 cm~2。4.激光测量比接触测量客观、准确,可以重复并易取得统一标准,为骨胳测量提供一种较好方法。根据所测肱骨头半径与关节面张角,即能绘出肱骨头关节面的图形,计算出关节面曲率。本文对设计、制造肱骨头提供了国人数据,也可为肱骨头生物力学的研究提供参考。     

Somatotopic organization of corticospinal and corticotrigeminal neurons in the rat

The method of retrograde axonal transport of horseradish peroxidase was employed to examine the topographic organization of corticospinal and corticotrigeminal neurons in the rat. In both the first somatic sensory (SI) area and the motor (MI) area of the cortex these labeled corticofugal neurons, all of which are found in layer V, are grouped in a well organized, somatotopic pattern. Corticospinal projections which extend to lumbar levels of the spinal cord originate only from neuronal somata located in the hindlimb representation of SI and MI. Those neurons projecting to the cervical enlargement have somata mainly in the forelimb representation of SI and MI and the ventrolateral part of the trunk representation within SI. Cortical projections to the rostral cervical spinal segments appear to originate mainly from the neck and posterior head representations of SI and MI, though this conclusion is clearest for SI. Finally, neurons located exclusively within the head, muzzle, and vibrissal representation of SI project to the spinal trigeminal complex. Corticofugal neurons near the frontal pole and in an area of cortex ventrolateral to SI also project to the spinal cord. The areas involved are probably homologous to the supplementary motor (MII) and second somatic sensory (SII) areas respectively. The corticospinal and corticotrigeminal projections from these areas also appear to be organized in a somatotopic manner.It is concluded that in the rat, as in other species, the corticospinal and corticotrigeminal neurons in the sensorimotor cortex are arranged somatotopically. The somatotopic pattern found correlates remarkably well with that determined by single unit, evoked potential and cortical stimulation techniques.     

Dependence of the anterior olfactory area self-stimulation upon the lateral hypothalamic area

The functional relation between the anterior olfactory area (AO) and the lateral hypothalamic area (LH) was examined in a self-stimulation situation. Bar-pressing responses for AO sitmulation were suppressed by unilateral injection of procaine, and enhanced by glutamate, into LH. Neither procaine nor glutamate injected into AO had any influence upon LH self-stimulation. It is unlikely that the procaine effect was due to motor disturbance because similar injection of procaine into LH did not disturb the performance of a one-way avoidance task. It appears that the rewarding effect of AO stimulation is dependent upon the excitation of the more caudal structures including LH.     

大鼠视前内侧区的传出性神经纤维联系—WGA—HRP法研究

应用WGA-HRP顺行轴突运输研究大鼠视前内侧区传出性神经纤维投射。结果表明:视前内侧区的上行投射向嘴侧经斜角带进入外侧隔核;经髓纹进入缰核;经无名质进入杏仁前区及经终纹进入杏仁内侧核,另有标记纤维经内侧前脑束向外下行,经视束上方进入杏仁内侧核。下行投射经内侧前脑束进入下丘脑室旁核、外侧区、内侧核、后核、弓状核、乳头体前腹核和乳头体上核。继续向尾侧,标记纤维进入中脑腹侧背盖区,并投射到中缝正中核及中缝背核。     

儿童及青少年中央颞区放电的临床分析

目的:探讨儿童及青少年中央颞区癎样放电的特征和临床意义。方法:回顾分析近9年在同步录像脑电图(VEEG)或动态脑电图(AEEG)监测中具有中央颞区癎样放电的儿童和青少年的临床表现及与神经影像学异常的关系。结果:具有中央颞区癎样放电的儿童和青少年共452例,占同期接受EEG监测儿童及青少年的9．5％,占EEG各种癫癎样异常的15．4％。监测到中央颞区放电的平均年龄为7．28±3．15岁(1-17岁)。临床诊断包括伴中央颞区棘波的儿童良性癫癎(BECT)179例(39．6％),症状性或隐源性癫癎154例(34．1％),热性惊厥21例(4．7％),从无癫癎发作98例(21．7％)。在354例有癫癎发作者中235例(66％)为部分运动性发作,102例(28．7％)为全身强直阵挛发作;其他发作类型包括不典型失神发作9例(2．5％),肌阵挛发作6例(1．7％),负性肌阵挛发作4例(1.1％),痉挛发作3例(0．8％)。少数患者有一种以上发作形式。在283例有神经影像学记录的患者中,50例(17．7％)异常,其中仅10例异常部位与放电部位基本一致。结论:儿童及青少年中央颞区放电具有以下特点:①明显的年龄依赖性;②病因具有高度异源性,包括特发性、隐源性和症状性病因;③各种病因的中央颞区癎样放电均有一部分不伴有临床发作;④仅根据发作类型和EEG特征难以区分特发性和症状性病因,需要结合全面的临床资料作出诊断;⑤静止性脑结构病变不一定与中央颞区放电有直接关系。