基因多态性（下）（Polymorphisms PartⅡ）

以绘制人类基因单体型图为目标的国际Hapmap计划也接受尾声。 基于SNP信息的基因组药理学已经开始实际应用。 个性化医疗在现实医疗中正在生根发芽。 接着上回由东大医科研的中村祐辅教授继续进行讲解。[编者按]     

中国蝴蝶新种记述（Ⅰ）（鳞翅目）

记载采自湖南省的中国蝴蝶3新种,模式标本保存在湖南省东安县第一中学。     

中国蝴蝶新种记述（Ⅱ）（鳞翅目）

记载采自河南省、四川省和云南省的中国蝴蝶8新种,模式标本保藏在河南省科学院和河南师范大学生物系。     

正（误）、宜用（不宜用）的部分生理学名词（术语）

在杂志和书刊上经常见到一些误用或不宜用的生理学术语,自然科学专业名词(包括医学名词)一律以全国自然科学名词审定委员会公布的名词为标准。考虑到有些专业名词多年来未审定,根据近年来科学出版社、高等教育出版社的图书编写要求,中华医学杂志和中国药理学报的投稿要求,     

后记（英文）

正Half a century ago,the first discovery of the Paleocene vertebrates at Dinghuawu,Xiaoshi,Huaining County opened a door for understanding the Paleocene vertebrate fauna in the Qianshan Basin,Anhui Province,China.Since 1970,colleagues from the Institute of Vertebrate Paleontology and Paleoanthropology(IVPP),Chinese Academy of Sciences have carried out a long term and continuous investigations to the Qianshan Paleocene,with     

病毒（一）

病毒的化学成分,形态结构,增殖等特点,均显示出它是一种独特的生命形式。     

表观遗传学解析（上）（基因组概况之一）

由哺乳类所代表的多细胞生物，由于来自一个受精卵（也就是说只有一个细胞），对于体内的任何组织的任何细胞来说，除免疫细胞等特殊情况之外，其中的任何细胞的基因组序列都相同。[第一段]     

方程N′（t）=r（t）N（t）（1—bN（t—T）—cN^2（t—T））正平衡点的全局吸引性

本文给出保证平方Logistic方程N′（t）=r(t)N(t)(1-bN(t-T)-cN^2(t-T))的每一正解N（t)趋于正平衡点N^*的一组充分条件。改进了Gapalsamy,Ladas和罗交晚等人的结果。     

促黄体素(LH)和人绒毛膜促性腺激素(hCG)在原索动物神经系统、哈氏窝和性腺中的分布

用抗人LH和hCG特异性抗体对原索动物神经系统、哈氏窝和性腺进行了免疫细胞化学定位。结果表明,文昌鱼脑泡和神经管中有两种不同LH-和hCG-样免疫反应阳性细胞,而皱瘤海鞘神经节对LH和hCG抗体则显免疫阴性反应。同时,首次发现在原索动物性腺(卵巢和精巢)发育早期均存在LH-和hCG-样免疫反应阳性细胞,阳性物分布在原索动物卵原细胞的胞质、核质和核仁膜以及精巢中早期生精细胞。后来,随卵巢发育和成熟,这些阳性物仍分布在卵母细胞质膜、胞质、核膜和核质上,而精巢中精细胞和精子则显免疫阴性。这些结果可为LH和hCG直接参与调节原索动物性腺发育和成熟提供形态学的新证据。     

雌激素受体α和β亚型在文昌鱼神经系统、哈氏窝和性腺中的定位

用兔抗人ER-α和ER-β多克隆抗体对文昌鱼神经系统、轮器哈氏窝和性腺进行免疫细胞化学的定位研究。结果揭示幼年和成年两性不同发育时期文昌鱼在这些部位分布ER-α和ER-β蛋白。ER-α定位在端脑、中脑、后脑和神经管中大多数神经细胞核,少数在胞质及其突起和神经纤维,ER-β则定位在细胞质或细胞膜上,少数在核内。ER—α免疫阳性物质主要分布在哈氏窝下层的上皮细胞核,少数在上层细胞质,β受体则在上层细胞核。在性腺,ER-α分布在卵巢中卵原细胞和小生长期卵母细胞胞质与核仁,生发泡(核)显免疫阴性,在大生长期卵母细胞核膜和核仁的免疫阳性显著增强,成熟期则在卵细胞生发泡表达,ER-β免疫阳性物质分布在卵原细胞和早期卵母细胞质以及成熟卵细胞的卵被膜检测到,生发泡显免疫阴性。在精巢,这两种ER亚型均定位在精原细胞、初级与次级精母细胞和足细胞质,精子细胞在胞核,精子显免疫阴性。另外,双染结果还揭示ER-α和ER-β在上述部位多数共存于同一细胞,少数在不同细胞表达,且在细胞定位有不同。首次发现这两种雌激素受体亚型在文昌鱼有广泛分布,它们介导雌激素对文昌鱼神经内分泌组织的调节作用。α和β受体在靶细胞定位的不同,提示两者在介导雌激素信号路线和基因转录机制可能有不同生理作用。     

Photoperiodic modulation of testicular LH receptors in the bank vole (Clethrionomys glareolus)

The temporal changes in testicular binding of 125I-labelled hCG in juvenile bank voles (18 days of age, born and reared in a 18L:6D photoperiod) exposed to a long (18L:6D, Group L) or short (6L:18D, Group S) photoperiod for 0, 3, 7, 14 and 42-56 days were investigated. During testicular maturation, in Group L, there was a slight initial decrease in LH receptor numbers per testis followed by a marked prepubertal rise during the initial phase of rapid testicular growth after which a decrease took place. In Group S, during testicular regression, the temporal changes in LH receptor numbers per testis resembled those of Group L except that the corresponding increase in hCG binding during the initial week was considerably less marked and the receptor numbers remained thereafter at a significantly lower level than in Group L. Leydig cell count indicated that the observed changes in LH receptors per testis were due to changes in the number of Leydig cells as well as in LH receptors per Leydig cell. The present results indicate, that (1) photoperiod is an important modulator of testicular LH receptor numbers in this species, (2) photoperiod or age has no significant effect on the binding affinity of LH receptors, (3) short photoperiods arrest the induction of LH receptors as well as the increase in Leydig cell numbers associated with normal testicular maturation, and (4) changes in LH receptor numbers per testis correlate well with the photoperiod-induced changes in androgen biosynthesis, spermatogenesis and Leydig cell morphology observed in our previous studies.     

Orexin-B-like immunoreactivity localized in both luteinizing hormone- and thyroid-stimulating hormone-containing cells in the Nile tilapia (Oreochromis niloticus) pituitary

Immunohistochemical techniques were employed to examine orexin-like immunoreactivities in the pituitary of the Nile tilapia (Oreochromis niloticus). Rabbit anti-orexin-A serum and mouse anti-orexin-B monoclonal antibodies were used as primary antibodies. Orexin-B immunoreactive cells corresponded to luteinizing hormone (LH)- or thyroid-stimulating hormone (TSH)-containing cells, and all LH- and TSH-containing cells were immunoreactive for orexin-B. However, we found no orexin-A immunoreactive cells in the pituitary. In the Nile tilapia, an orexin-B-like substance may be secreted from LH- or TSH-containing cells and may regulate pituitary function, rather than the orexin-A-like substance in the pituitaries of Japanese seaperch and medaka.     

Luteinizing hormone receptor-mediated effects on initiation of spermatogenesis in gonadotropin-deficient (hpg) mice are replicated by testosterone

Testosterone (T) is an absolute requirement for spermatogenesis and is supplied by mature Leydig cells stimulated by LH. We previously showed in gonadotropin-deficient hpg mice that T alone initiates qualitatively complete spermatogenesis bypassing LH-dependent Leydig cell maturation and steroidogenesis. However, because maximal T effects do not restore testis weight or germ cell number to wild-type control levels, additional Leydig cell factors may be involved. We therefore examined 1). whether chronic hCG administration to restore Leydig cell maturation and steroidogenesis can restore quantitatively normal spermatogenesis and testis development and 2). whether nonandrogenic Leydig cell products are required to initiate spermatogenesis. Weanling hpg mice were administered hCG (0.1-100 IU i.p. injection three times weekly) or T (1-cm subdermal Silastic implant) for 6 weeks, after which stereological estimates of germinal cell populations, serum and testicular T content, and testis weight were evaluated. Human CG stimulated Leydig cell maturation and normalized testicular T content compared with T treatment where Leydig cells remained immature and inactive. The maximal hCG-induced increases in testis weight and serum T concentrations were similar to those for T treatment and produced complete spermatogenesis characterized by mature, basally located Sertoli cells (SCs) with tripartite nucleoli, condensed haploid sperm, and lumen development. Compared with T treatment, hCG increased spermatogonial numbers, but both hCG and T had similar effects on numbers of spermatocytes and round and elongated spermatids per testis as well as per SC. Nevertheless, testis weight and germ cell numbers per testis and per SC remained well below phenotypically normal controls, confirming the involvement of non-Leydig cell factors such as FSH for quantitative normalization of spermatogenesis. We conclude that hCG stimulation of Leydig cell maturation and steroidogenesis is not required, and that T alone mostly replicates the effects of hCG, to initiate spermatogenesis. Because T is both necessary and sufficient for initiation of spermatogenesis, it is likely that T is the main Leydig cell secretory product involved and that additional LH-dependent Leydig cell factors are not essential for induction of murine spermatogenesis.     

Leucine-enkephalin-like immunoreactivity is localized in luteinizing hormone-producing cells in the axolotl (Ambystoma mexicanum) pituitary

In this study, we used immunohistochemical techniques to determine the cell type of leucine-enkephalin (Leu-ENK)-immunoreactive cells in the axolotl (Ambystoma mexicanum) pituitary. Immunoreactive cells were scattered throughout the pars distalis except for the dorso-caudal portion. These cells were immuno-positive for luteinizing hormone (LH), but they were immuno-negative for adrenocorticotrophic, growth, and thyroid-stimulating hormones, as well as prolactin. Immunoelectron microscopy demonstrated that Leu-ENK-like substance and LH co-localized within the same secretory granules. Leu-ENK secreted from gonadotrophs may participate in LH secretion in an autocrine fashion, and/or may participate in the release of sex steroids together with LH.     

Formation and ultrastructural organization of gonads in Oikopleura gracilis Lohmann, 1896 (Urochordata: Appendicularia)

This study deals with the formation and ultrastructural organization of the gonads in a common species of appendicularian, Oikopleura gracilis, from Peter the Great Bay. Light microscopy observations show that the gonads develop from a transparent primordium that is located in the basolateral part of the gonad cavity; the primordium increases in size in the process of development and differentiates into the testis and ovary. The testis is covered by a single layer of ultrastructurally uniform follicular epithelium and contains a population of proliferating male gonocytes. The ovary contains two types of germ line nuclei, which are large polyploid nuclei that belong to the auxiliary cells and small meiotic nuclei of the oocytes. The two nuclei types, together with a common cytoplasm, form a syncytium of the ovary, or the coenocyst. As in the dioecious Oikopleura dioica, the coenocyst of O. gracilis produces naked oocytes that are devoid of a type III follicular membrane. The coenocyst is covered by a single-layered follicular epithelium, in which two cell types can be distinguished ultrastructurally. Thus, the synchronous maturation of sex products in O. gracilis is achieved by the formation of the germ-line syncytium in the testis and the coenocyst in the ovary, which generates a large number of simultaneously ripening oocytes that are competent for fertilization.     

Regulation of 5 alpha-reductase activity in cultured immature leydig cells by human chorionic gonadotropin

The present studies examined the hormonal regulation of 5 alpha-reductase activity in cultured immature rat Leydig cells. Within the testis 5 alpha-reductase was concentrated in the interstitial cell compartment, and among interstitial cells, the enzyme was localized primarily in Band 3 of Percoll density gradients, which contains the majority of Leydig cells. Among various factors reported previously to stimulate testicular 5 alpha-reductase activity when administered in vivo to immature rats (LH/hCG, FSH, luteinizing hormone releasing hormone or prolactin), only LH/hCG directly stimulated 5 alpha-reductase activity of cultured immature Band 3 cells. Neither growth hormone which was reported previously to stimulate hepatic 5 alpha-reductase activity, nor insulin, insulin-like growth factor-I, or epidermal growth factor, which have been reported to modulate Leydig cell function, had any effect on 5 alpha-reductase activity of Band 3 cells. These studies suggest that the major factor directly stimulating 5 alpha-reductase activity in Leydig cells during early maturation is LH. However, it is possible that other factors acting indirectly may modulate the maturational rise in 5 alpha-reductase activity.     

Structural proteins in sexual differentiation of embryonic gonads

Sexual differentiation of embryonic gonads was studied by immunocytochemical analysis of cytoskeleton, basement membrane and extracellular matrix. The epithelial cells of the prospective gonadal region in both sexes contained vimentin and desmin intermediate filament proteins but not cytokeratin. Basement membrane components laminin, collagen types IV and V, heparan sulfate proteoglycan, and fibronectin were seen in an unorganized form in the extracellular space. The development of the gonads started by proliferation of the pregonadal epithelial cells, which formed separate clusters and loose mesenchyme. In the male gonad the clusters joined together into elongated cords, outlined by basement membrane components. The cord cells became polarized epithelial cells, and cytokeratin appeared with the disappearance of desmin in their cytoplasm. Desmin and vimentin remained in the interstitial cells. In the female gonad the clusters were smaller, and the cords were irregular in shape and size. Desmin disappeared from the cord cells and cytokeratin appeared, but more slowly and less well polarized than in the testis. The present results show that after common early development, the sexual differences in gonads emerge as different organization of the internal epithelial tissue with different timing of changes in intra- and extracellular components.     

Comparison of monoclonal luteinizing hormone (LH) receptor antibody and LH binding sites in vibratome sections of rat ovary by immunohistochemistry

To identify luteinizing hormone (LH) receptors, a monoclonal antibody (MAb) was produced by immunization of Balb/c mice with rat luteal cell membranes. Hybridomas, produced by a method for proteins of low antigenicity, were selected by competition with [125I]-hCG (LH) for luteal membrane binding. Conditions for analysis of LH receptor antibody (IgG2b isotype) binding by immunohistochemistry with an avidin-biotin-peroxidase complex were examined and results compared to localization of bound hCG, to detect receptors. By light microscopy, both bound hCG and the LH receptor antibody were located on luteal cell surfaces. In addition, the LH receptor antibody was associated with luteal cell cytoplasm. Cell surface membrane binding, but not cytoplasmic staining, was reduced in ovaries from rats injected with hCG. By electron microscopy, LH receptor antibody was observed in patches on luteal cell surface membranes and was associated with polysomes, small vesicles, and occasionally with discrete areas of endoplasmic reticulum. Therefore, detection of LH receptors with bound hCG may be limited to receptors found on cell surfaces, while additional LH receptors are revealed by use of a receptor antibody. The cytoplasmic LH receptor may represent stages in the processing of receptor protein. Furthermore, the methodology used in this study should be generally useful for immunohistochemistry with other MAb to receptors.