Differential fos activation in virgin and lactating mice in response to an intruder

Lactating (L) mice display fierce aggression towards novel, male mice, while virgin (V) mice do not. This study compares patterns of brain activation in V and L mice in response to a novel intruder using immunohistochemical detection of Fos (Fos-IR). Animals were sampled 120 min after either a sham or real 10 min test with a male intruder. L mice were aggressive towards intruders, but V mice were not. In general, Fos-IR for both groups increased with exposure to an intruder, with L mice showing higher increases in Fos-IR than V mice. In only medial preoptic nucleus and ventral portion of bed nucleus of stria terminalis (BNST) was Fos-IR significantly increased in both groups with testing. In V mice, testing resulted in Fos-IR increases in an additional 10 regions examined that did not reach significance in L mice, including lateral septum, lateral and medial preoptic areas, and anterior hypothalamus. Fos-IR also increased with testing in nine regions unique to L mice, including the mitral and granular layers of accessory olfactory bulb, regions of the amygdala, dorsal BNST, and caudal portions of the hypothalamic attack area. These increases in Fos-IR with testing suggest alterations in the circuitry governing response to pheromonal cues and imply some commonalities between the circuitries governing maternal aggression and intermale aggression. These results support the hypothesis that pregnancy and lactation induce substantial changes in brain circuitry and function; changes that enable maternal defense of offspring by altering the neural response to an intruder male.     

面神经颞支的应用解剖学研究

目的:为预防额颞区手术和翼点入路的颅内手术损伤面神经颞支提供解剖学资料。方法:60侧成人头部标本,解剖观测面神经颞支的分支、行程及层次。结果:(1)面神经颞支多为2~4支,占95.00％(57侧)。(2)面神经颞支离开腮腺上缘后向前上走行,从颧弓浅面跨过进入额颞区,后走行于浅筋膜和颞筋膜浅层之间;在腮腺上缘及颧弓上缘处面神经颞支的最后1支距耳屏尖的距离分别为(23.79±0.27)mm和(30.67±0.37)mm。结论:面神经颞支入肌前在颧弓以下一段位置较深、以上表浅。从耳屏尖向前23mm范围内无该神经通过,为手术安全区。     

旋股外侧动脉升支阔筋膜张肌支髂骨瓣的解剖学研究及临床意义

目的 :探讨带旋股外侧动脉升支阔筋膜张肌支髂骨瓣的解剖及应用要点。方法 :在 2 5侧经动脉灌注红色乳胶的成人下肢标本上 ,重点观测旋股外侧动脉升支阔筋膜张肌支的走行、分支、发出点和外径等。结果 :旋股外侧动脉升支的阔筋膜张肌支上行支发出点距髂前上棘平面 7.1± 2 .3cm ,外径 1.2± 0 .8mm ,该支又分出 2～ 3支外径在 0 .3mm～ 0 .5mm的小分支从阔筋膜张肌后份进入肌质 ,上行至肌起始处达髂骨 ;其下行支发出点距髂前上棘平面 7.9± 1.8cm ,外径 1.3± 0 .8mm。结论 :旋股外侧动脉升支阔筋膜张肌支髂骨瓣具有手术可行性和实际应用价值     

Efferent connections of the medial prefrontal cortex in the rabbit

The different cytoarchitectonic regions of the medial prefrontal cortex (mPFC) have recently been shown to play divergent roles in associative learning in rabbits. To determine if these subareas of the mPFC, including areas 24 (anterior cingulate cortex), 25 (infralimbic cortex), and 32 (prelimbic cortex) have differential efferent connections with other cortical and subcortical areas in the rabbit, anterograde and retrograde tracing experiments were performed using thePhaseolus vulgaris leukoagglutinin (PHA-L), and horseradish peroxidase (HRP) techniques. All three areas showed local dorsal-ventral projections into each of the other areas, and a contralateral projection to the homologous area on the other side of the brain. All three also revealed a trajectory through the striatum, resulting in heavy innervation of the caudate nucleus, the claustrum, and a lighter projection to the agranular insular cortex. The thalamic projections of areas 24 and 32 were similar, but not identical, with projections to the mediodorsal nucleus (MD) and all of the midline nuclei. However, the primary thalamic projections from area 25 were to the intralaminar and midline nuclei. All three areas also projected to the ventromedial and to a lesser extent to the ventral posterior thalamic nuclei. Projections were also observed in the lateral hypothalamus, in an area just lateral to the descending limb of the fornix. Amygdala projections from areas 32 and 24 were primarily to the lateral, basolateral and basomedial nuclei, but area 25 also projected to the central nucleus. All three areas also showed projections to the midbrain periaqueductal central gray, median raphe nucleus, ventral tegmental area, substantia nigra, locus coeruleus and pontine nuclei. However, only areas 24 and the more dorsal portions of area 32 projected to the superior colliculus. Area 25 and the ventral portions of area 32 also showed a bilateral projection to the parabrachial nuclei and dorsal and ventral medulla. The dorsal portions of area 32, and all of area 24 were, however, devoid of these projections. It is suggested that these differential projections are responsible for the diverse roles that the cytoarchitectonic subfields of the mPFC have been demonstrated to play in associative learning.     

The paraventricular nucleus of hypothalamus mediates the pressor response to noradrenergic stimulation of the medial prefrontal cortex in unanesthetized rats

The medial prefrontal cortex (MPFC) is a structure that is also involved in cardiovascular modulation. The injection of norepinephrine (NE) into the prelimbic (PL) area of the MPFC of unanesthetized rats evokes a pressor response which is mediated by acute vasopressin release. Vasopressin is synthesized by magnocellular cells of the paraventricular (PVN) and supraoptic nucleus (SON) of the hypothalamus. In the present study, we endeavored to determine which vasopressin-synthesizing hypothalamic nucleus is involved in the pressor pathway activated after NE injection into the PL area of the MPFC. We report here that lidocaine microinjection into the SON did not change the pressor response evoked by NE injection into the PL. However, the response to NE was blocked by prior injection of lidocaine or CoCl₂ into the PVN, indicating that this area is responsible for the mediation of this pressor response. A neuroanatomic experiment in which the neuronal tracer biotinylated dextran amine (BDA) was microinjected into the MPFC showed a lack of axons or neuronal cell bodies in the PVN, indicating that there are no direct connections between the PL area of the MPFC and the PVN. The results suggest that the PVN is involved in the mediation of the pressor response to NE in the PL area and that this pathway must relay in other brain structures before reaching the PVN.     

尺动脉腕背支升支皮瓣的应用解剖学研究

目的　为临床应用尺动脉腕背支升支皮瓣修复手部创面 ,提高治疗效果提供解剖学基础。方法　用新鲜成人男性上肢标本 1 6侧 ,采用显微解剖学技术 ,对尺动脉腕背支升支的起始、走行、分支及分布进行解剖学观察和测量。结果　尺动脉腕背支起始于尺动脉的尺侧 ,距豌豆骨上方 4 2 .6 0± 8.2 0mm ,起始处外径1 .4 6± 0 .32mm ,长 1 1 .4 6± 8.2 0mm。尺动脉腕背支与尺神经手背支伴行 ,穿过尺侧腕屈肌腱的深面 ,从掌侧向后内侧斜行 ,两者成锐角 ,平均 38.6 0± 8.2 0°,行至 1 1 .4 6mm处分为升支与降支。升支穿深筋膜进入皮下组织 ,沿前臂内侧缘上行 1 2 2 .4 0± 1 3.80mm处再分为细小分支 ,升支起始部的外径为 0 .6 2± 0 .2 8mm。结论　尺动脉腕背支升支皮瓣是以尺动脉腕背支升支为蒂 ,可在前臂尺侧设计大面积岛状皮瓣 ,通过转位修复腕部和手部创伤及挛缩瘢痕切除术后的创面 ,不牺牲前臂主要血管 ,手术操作易于掌握     

带血管股骨片作支撑体阴茎再造的解剖基础

在45侧成年男性下肢标本上,观测了股中间肌近端的动脉来源、分支,走行和旋股外侧动脉降支。股中间肌近端动脉来源较多,发于旋股外侧动脉的57.7%,其骨膜支长3.6cm,发出后向下斜行至骨面,贴骨面呈节段分布,长达6.0cm 以上。旋股外侧动脉降支外径3.2mm,长9.2cm。经尸体摹拟手术,可设计以该血管为蒂的股骨瓣作支撑体与股前外侧皮瓣转位再造阴茎。本文对手术设计、骨片切取和血管蒂的处理等有关应用解剖学要点进行了讨论。     

Mouse killing and hyperreactivity following lesions of the medial hypothalamus, the lateral septum, the bed nucleus of the stria terminalis, or the region ventral to the anterior septum

Electrolytic lesions in the medial hypothalamus, the lateral septum, or the region ventral to the anterior septum induced home cage mouse killing in 85 to 100% of rats when tested 2 days postoperatively and in 50 to 70% when tested at 21 days. When tested in a novel and larger test chamber, 100% of the rats with medial hypothalamic lesions killed mice at 2 days postoperatively but only 30% killed at 21 days postoperatively. Ten to thirty percent of animals with lesions of the lateral septum or of the region ventral to the anterior septum killed at any time in the novel environment. Lesions of the stria terminalis produced a slight increase in mouse killing in both the home cage and the novel environment. A high level of reactivity was produced by lesions of the medial hypothalamus, the lateral septum or the region ventral to the anterior septum but only that caused by the medial hypothalamic lesions was sustained over the 21 day test period. These results support previous evidence that the lateral septum, the region ventral to the anterior septum, and the medial hypothalamus are each important areas modulating mouse killing.     

LH syndrome and brain catecholamine levels after lesions of the nigrostriatal bundle

Lesions of the nigrostriatal bundle (NSB), whose fibers pass through the medial portions of the internal capsule and the immediately adjacent lateral hypothalamus (LH), produced a more severe aphagia, adipsia, and disturbance of water regulation than did lesions of the medial forebrain bundle (MFB). When deprived of food, animals with NSB lesions drank significantly less than controls and animals with MFB lesions. NSB lesions also produced greater decreases in telencephalic content of the catecholamines than MFB lesions, while the reverse was true for serotonin. Water intake during food deprivation was highly correlated with telencephalic catecholamine levels in animals with NSB lesions. Thus, the inability to regulate water intake in the absence of food, one of the characteristic and long lasting effects of the LH syndrome, appears to be due to destruction of the NSB and the consequent decline in telencephalic content of catecholamines.     

Arborization of axons in oculomotor nucleus identified by vestibular stimulation and intra-axonal injection of horseradish peroxidase

Summary Axons in the medial rectus (MR) subdivisions of the oculomotor nucleus were identified by horizontal rotation and by electrical stimulation of the vestibular nerves and abducens nuclei. Three types of axons (vestibular type I and II and abducens interneurons) were then injected intra-axonally with horseradish peroxidase (HRP). Each injected axon was reconstructed under the microscope in the frontal and horizontal planes and terminal arborization and boutons contacting with MR motoneurons were studied. The MR motoneurons were identified by retrograde uptake of HRP, HRP being injected in the MR muscle prior to the intra-axonal experiment.The main types of horizontal canal-related axons were as follows: (1) ATD-unilateral termination axons: Most type I axons were of this type. Axons ascended in ascending tract of Deiters (ATD) to the oculomotor nucleus and terminated in ipsilateral MR area. (2) ATD-bilateral termination axons: Very few secondary canal responsive axons were in this group. Axons ascended in ATD to the oculomotor nucleus and terminated in MR motoneuron areas bilaterally and in the Edinger-Westphal nucleus. (3) MLF-bilateral termination axons: Most type II neurons were in this group. Axons went up in the contralateral MLF and into both oculomotor nuclei. Their branches distributed to several motoneuron areas but only infrequently to the MR area; and to the Edinger-Westphal nucleus. (4) AB interneuron axons: Axons ascended in the MLF contralateral to cells of origin and terminated in the contralateral MR motoneuron area.Supported by USPHS Grant No. 06658