Is CAG sequence length in the androgen receptor gene correlated with finger-length ratio?

Manning, Bundred, Newton, and Flanagan reported a significant correlation of .29 in a sample of 50 British males between the length of a repeated sequence on the androgen receptor gene and 2D:4D finger-length ratio on the right hand. We report a 2nd failure to replicate this result. Ours was a sample of 182 Australian male twins studied for other purposes, for whom both measures were available. The result was a nonsignificant correlation of −.055. A similar result was obtained for female twins, and for comparisons within sibling pairs. Correlations are also reported for left hands and right-left differences--the last showed a weak tendency toward replication.     

Memory-Enhancing Treatments Do Not Reverse the Impairment of Inhibitory Avoidance Retention Induced by NMDA Receptor Blockade

The aim of the present research was to verify whether the impairment of retention induced by the N-methyl-d-aspartate (NMDA) receptor blocker (+)-10,11-dihydro-5-methyl-5H-dibenzo[a,d]cycloheptene-5,10 imine (MK-801) can be reversed by memory-enhancing treatments. Adult female Wistar rats were trained and tested in a step-down inhibitory avoidance task (0.3-mA foot shock, 24-h training-test interval). Animals were given an ip injection of saline (SAL) or MK-801 (0.0625 mg/kg) 30 minutes before training, and an ip injection of SAL, epinephrine (EPI) (25 microg/kg), the opioid receptor antagonist naloxone (NAL) (0.4 mg/kg), the glucocorticoid receptor agonist dexamethasone (DEX) (0.3 mg/kg), or glucose (GLU) (320 mg/kg) immediately after training. There was an impairment of inhibitory avoidance retention in the MK-801-SAL, MK-801-EPI, MK-801-NAL, MK-801-DEX, and MK-801-GLU groups. There was an enhancement of retention in the SAL-EPI, SAL-NAL, SAL-DEX, and SAL-GLU groups. A control experiment showed that the amnestic effects of MK-801 could not be attributed to decreased reactivity to the foot shock. The results suggest that memory-enhancing treatments directed at modulatory mechanisms do not reverse the memory impairment induced by NMDA receptor blockade.     

催产素及受体基因与社会适应行为

作为一种在哺乳动物分娩和泌乳中起神经调节作用的激素, 催产素(oxytocin, OT)在人类的母婴关系和社会关系中也发挥着重要作用。研究发现催产素及其受体基因与人类的社会适应行为关系密切。催产素会影响亲子依恋和父母教养行为, 也能促进人际信任及慷慨行为; 同时, 不同催产素受体(oxytocin receptor, OXTR)基因型的个体, 在亲子关系和一些亲社会行为方面都表现出了差异。来自于激素和基因水平的研究提示我们, 催产素及其受体基因可能是通过促进社会识别、调节共情以及降低恐惧、减缓焦虑来影响人类一系列的社会适应行为。未来的研究应考虑结合分子遗传学和神经科学的研究方法, 从基因－激素－行为三个层面系统的研究催产素影响社会行为的分子过程和认知神经过程。     

治疗糖尿病创新药物研究

本论文从治疗2型糖尿病药物应用现状出发,通过对2型糖尿病病理的认识,新发现的主要受体和相关药靶等方面进行分析。指出随着对糖尿病认识的深入发展,治疗糖尿病创新药物研究的发展趋势也发生了相应的变化,就是从局部治疗到全身综合考虑,从药物外部直接地干预到增强自身调节功能。为治疗2-型糖尿病药物发展指明了方向。     

鼻咽癌组织VEGF、TNF—α及其受体VEGFR1、P55的表达及意义

观察鼻咽癌黏膜上皮中血管内皮生长因子（VEGF）、肿瘤坏死因子α（TNF—α）及受体血管生长因子1（VEGFR1）,肿瘤坏死生长因子受体蛋白55（P55）的表达情况,探讨其在鼻咽癌发病及进展中的意义。我们应用免疫组化SP法检测60例鼻咽癌和60例正常鼻黏膜上皮组织VEGF、TNF—α及VEGFR1、P55表达情况,分析其在鼻咽癌组织中的表达变化及意义。结果显示鼻咽癌黏膜上皮的VEGF、TNF—α、VEGFR1、P55表达高于正常鼻黏膜上皮。因此VEGF、TNF—α及其受体VEGFR1、P55在鼻咽癌黏膜上皮中过度表达,可能参与鼻咽癌的发病及疾病进展,对于鼻咽癌的预防及治疗具有重要意义。     

Post-training infusion of glutamate into the bed nucleus of the stria terminalis enhanced inhibitory avoidance memory: An effect involving norepinephrine

This study examined an interaction between glutamate and norepinephrine in the bed nucleus of the stria terminalis (BNST) in modulating affective memory formation. Male Wistar rats with indwelling cannulae in the BNST were trained on a one-trial step-through inhibitory avoidance task and received pre- or post-training intra-BNST infusion of glutamate, norepinephrine or their antagonists. Results of the 1-day test indicated that post-training intra-BNST infusion of dl-2-amino-5-phosphonovaleric acid (APV) impaired retention in a dose- and time-dependent manner, while infusion of glutamate had an opposite effect. Co-infusion of 0.2 μg glutamate and 0.02 μg norepinephrine resulted in marked retention enhancement by summating non-apparent effects of the two drugs given at a sub-enhancing dose. The amnesic effect of 5.0 μg APV was ameliorated by 0.02 μg norepinephrine, while the memory enhancing effect of 1.0 μg glutamate was attenuated by 5.0 μg propranolol. These findings suggest that training on an inhibitory avoidance task may alter glutamate neurotransmission, which by activating NMDA receptors releases norepinephrine to modulate memory formation via β adrenoceptors in the BNST.     

Olfaction as a model system for the neurobiology of mammalian short-term habituation

Olfaction represents an ideal model system for the study of mammalian habituation given that it is an anatomically relatively simple system with strong reciprocal connections to the limbic system, driving both reflexive and non-reflexive (motivated) behaviors that are easily quantifiable. Data are reviewed here demonstrating short-term habituation of the odor-evoked heart-rate orienting reflex described according to the criteria for habituation outlined by Thompson and Spencer [Thompson, R. F., & Spencer, W. A. (1966). Habituation: A model phenomenon for the study of neuronal substrates of behavior. Psychological Reviews, 73(1), 16–43]. A necessary and sufficient mechanism of short-term habituation is then described, which involves a metabotropic glutamate receptor mediated depression of afferent input to the piriform (primary olfactory) cortex. Finally, evidence for, and a mechanisms of, dishabituation of the orienting reflex and cortical adaptation are described.     

The ameliorating effect of oroxylin A on scopolamine-induced memory impairment in mice

Oroxylin A is a flavonoid and was originally isolated from the root of Scutellaria baicalensis Georgi., one of the most important medicinal herbs in traditional Chinese medicine. The aim of this study was to investigate the ameliorating effects of oroxylin A on memory impairment using the passive avoidance test, the Y-maze test, and the Morris water maze test in mice. Drug-induced amnesia was induced by administering scopolamine (1 mg/kg, i.p.) or diazepam (1 mg/kg, i.p.). Oroxylin A (5 mg/kg) significantly reversed cognitive impairments in mice by passive avoidance and the Y-maze testing (P<.05). Oroxylin A also improved escape latencies in training trials and increased swimming times and distances within the target zone of the Morris water maze (P<.05). Moreover, the ameliorating effects of oroxylin A were antagonized by both muscimol and diazepam (0.25 mg/kg, i.p., respectively), which are GABA(A) receptor agonists. Furthermore, oroxylin A (100 microM) was found to inhibit GABA-induced inward Cl(-) current in a single cortical neuron. These results suggest that oroxylin A may be useful for the treatment of cognitive impairments induced by cholinergic dysfunction via the GABAergic nervous system.     

Influence of chronic corticosterone and glucocorticoid receptor antagonism in the amygdala on fear conditioning

Glucocorticoid receptor activation within the basolateral amygdala (BLA) during fear conditioning may mediate enhancement in rats chronically exposed to stress levels of corticosterone. Male Sprague-Dawley rats received corticosterone (400 microg/ml) in their drinking water (days 1-21), a manipulation that was previously shown to cause hippocampal CA3 dendritic retraction. Subsequently, rats were adapted to the fear conditioning chamber (day 22), then trained (day 23), and tested for conditioned fear to context and tone (day 25). Training consisted of two tone (20s) and footshock (500 ms, 0.25 mA) pairings. In Experiment 1, muscimol (4.4 nmol/0.5 microl/side), a GABAergic agonist, was microinfused to temporarily inactivate the BLA during training. Rats given chronic corticosterone showed enhanced freezing to context, but not tone, compared to vehicle-supplemented rats. Moreover, BLA inactivation impaired contextual and tone conditioning, regardless of corticosterone treatment. In Experiment 2, RU486 (0, 0.3, and 3.0 ng/0.2 microl/side) was infused on training day to antagonize glucocorticoid receptors in the BLA. Corticosterone treatment enhanced fear conditioning to context and tone when analyzed together, but not separately. Moreover, RU486 (3.0 ng/side) selectively exacerbated freezing to context in chronic corticosterone-exposed rats only, but failed to alter tone conditioning. Serum corticosterone levels were negatively correlated with contextual, not tone, conditioning. Altogether, these suggest that chronic corticosterone influences fear conditioning differently than chronic stress as shown previously. Moreover, chronic exposure to corticosteroids alters BLA functioning in a non-linear fashion and that contextual conditioning is influenced more than tone conditioning by chronic corticosterone and BLA glucocorticoid receptor stimulation.     

Sensitivity in detecting facial displays of emotion: Impact of maternal depression and oxytocin receptor genotype

The current study examined sensitivity in detecting emotional faces among children of depressed and non-depressed mothers. A second goal was to examine the potential moderating role of the oxytocin receptor gene (OXTR rs53576), which has been linked to emotion recognition in the past. Participants included 247 children (ages 8–14). Children completed a forced choice emotion identification task. Maternal history of major depressive disorder during children's lives was associated with children's sensitivity in detecting emotional faces among children homozygous for the OXTR rs53576 G allele, but not among carriers of the A allele. Among G homozygotes, children of depressed mothers exhibited increased sensitivity in detecting sad faces, and reduced sensitivity in detecting happiness, compared to children of non-depressed mothers.