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1.
Nitric oxide (NO) is produced by nitric oxide synthases (NOSs) and plays an important role in all levels of reproduction from the brain to the reproductive organs. Recently, it has been discovered that all germ cells and Leydig cells in the cat testis exhibit stage‐dependent nuclear and cytoplasmic endothelial (eNOS) and inducible (iNOS)‐NOS immunoreactivity and cytoplasmic nicotinamide adenine dinucleotide phosphate‐diaphorase (NADPH‐d) reactivity. As a continuation of this finding, in this study, cellular localization of NADPH‐d and immunolocalization and expression of all three NOS isoforms were investigated in the intratesticular (tubuli recti and rete testis), and excurrent ducts (efferent ductules, epididymal duct and vas deferens) of adult cats using histochemistry, immunohistochemistry and western blotting. NADPH‐d activity was found in the midpiece of the spermatozoa tail and epithelial cells of all of ducts, except for nonciliated cells of the efferent ductules. Even though the immunoblotting results revealed similar levels of nNOS, eNOS and iNOS in the caput, corpus and cauda segments of epididymis and the vas deferens, immunostainings showed cell‐specific localization in the efferent ductules and region‐ and cell‐specific localization in the epididymal duct. All of three NOS isoforms were immunolocalized to the nuclear membrane and cytoplasm of the epithelial cells in all ducts, but were found in the tail and the cytoplasmic droplets of spermatozoa. These data suggest that NO/NOS activity might be of importance not only for the functions of the intratesticular and excurrent ducts but also for sperm maturation. Microsc. Res. Tech. 79:192–208, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   

2.
This study described the anatomy and histology of the male reproductive system in Chrysomela populi, which is an economically important species belonging to the family Chrysomelidae. Therefore, reproductive biology has been studied to combat this insect. As well as, the characters associated with the reproductive tract have been potential to discuss aspects of the system and to better understand the reproductive dynamics. The male reproductive system of C. populi has a pair of testes, a pair of vas efferentia and deferentia, a pair of seminal vesicles, a pair of accessory glands, an ejaculatory bulb, an ejaculatory duct, and an aedeagus. The testis consists of two flower-shaped lobes. Each testis has 20 sperm tubules (testicular follicles) containing cysts of germ cells at various developmental stages within the light orange peritoneal sheath. Testicular follicles are composed of three different (growth, maturation, and differentiation) zones. In the middle region of each testis joins with the vas efferens. The testis is attached to the seminal vesicle by a small stalk like vas efferens. In the lumen of the vas efferens, seminal vesicle, and vas deferens, sperms form clumps in the form of thin threads. The proximal end of the vas deferens is connected to the common ejaculatory duct. It joins with the ejaculatory bulb. Around the ejaculator bulb, there is a pair of convoluted, flat-surface tubular structure accessory glands. Posterior ejaculatory duct joins with the aedeagus.  相似文献   

3.
The histomorphology of the reproductive system and the germ cells has been useful to establish phylogenetic relationships in many insects. However, these elements remain little known in the Curculionidae. In this study, histomorphological structure of the male reproductive system of Tanymecus dilaticollis, which is economically important, is described, illustrated using stereomicroscopy, light microscopy, and scanning electron microscopy techniques, and discussed in relation to other Coleoptera species. Results showed that distinctive features of the male reproductive system of T. dilaticollis consist of a pair of yellowish testes, a pair of seminal vesicles, a pair of vasa deferentia, an ejaculatory duct, accessory glands, prostate glands, and aedeagus. Each testis is subdivided into two testicular follicles, enclosed by a peritoneal sheath. Each follicle of the mature testes is full sperm cysts with germ cells at various stages development of spermatogenesis. The testes have four types of germ cells (spermatogonia, spermatocytes, spermatids, and spermatozoa). They are occupied by the growth zone containing spermatogonia and spermatocytes, the maturation zone containing spermatids, while differentiation zone containing spermatozoa. There is a seminal vesicle at the center of each testis. Most mature sperms are stored in the seminal vesicle. Each testis is attached to the vas deferens by a stalk‐like seminal vesicle. In the distal part, vasa deferentia fuse with the ejaculatory duct. It is linked to the aedeagus. The provided results will contribute to the understanding of the reproductive cell biology of Curculionidae.  相似文献   

4.
Laser microdissection of individual mammalian chromosomes (> 2 µm) has been achieved though the use of a microscope slide coated with a polyethylene naphthalate (PEN) membrane. Although these slides have proved sufficient for larger chromosomes, they are insufficient for small chromosomes (< 1 µm). We have developed a new type of slide which allows laser microdissection of single Japanese quail microchromosomes (0.5 µm) and macrochromosomes (3–4 µm). To test the usefulness of these slides, a Japanese quail single nucleus, a macrochromosome, and a microchromosome were collected with Laser pressure catapulting, the B-actin gene was PCR amplified, and sequenced. The resulting PCR product was confirmed by nucleotide sequencing to be B-actin. These newly developed slides were shown to facilitate the laser microdissection of both Japanese quail macrochromosomes and microchromosomes.  相似文献   

5.
This work presents the male reproductive system morphology and histology of the water strider Gerris lacustris (Linnaeus 1758) (Gerridae, Heteroptera) using light microscopy and scanning electron microscopy. The male reproductive system of G. lacustris comprise of a pair of testes, two vasa deferentia, two seminal vesicles, an ejaculatory duct. There is no bulbus ejaculatorius and the long vas deferantia uniting to form a simple ductus ejaculatorius which is connected to the aedeagus. The testes are white colored and this cylindiric‐shaped structure lies along genital abdominal segment. The testicular follicles have three different development zones (growth zone, maturation zone, differentiation zone). Each testis has two follicles, which are not lined by a common peritoneal sheath and involving many cysts arranged in a progressive order of maturation from the distal to the proximal region; spermiogenesis occurs in mature males, finishing with the organization of sperm bundles. The testes are connected to the seminal vesicles, specialized sperm storage places, by the vas deferentia.  相似文献   

6.
Bauhinia forficata is a medicinal plant that has flavonoid components with hypoglycemic, antioxidant, hepatoprotective, antibacterial, antiviral and anti‐inflammatory action. Aim of this study is to evaluate the action of B. forficata alcoholic extract in the male genital system of adult male Wistar rats. For that, 20 adult male Wistar rats were distributed into two experimental groups: the B. forficata group, receiving B. forficata alcoholic extract (0.1 ml/10 g body weight/day) on alternate days, and the control group, receiving just the vehicle for 30 days straight both via gavage. On the 31st day, the animals were euthanized, and the testis and epididymis were collected for histopathological, biochemical, morphometric, and sperm count analysis. Mass spectrometry identified new compounds in the extract: trans‐caffeic acid, liquiritigenin, gallocatechin, and 2,4,6‐trihydroxyphenanthren‐2‐glycoside. Biochemical analysis showed higher total cholesterol levels in the testis and lower malondialdehyde levels in the testis and epididymis, in the B. forficata group. The mast cell count showed a reduction in degranulated mast cells in the caput region of the epididymis, in the B. forficata group. The luminal compartment of the caput and the epithelial of the epididymis cauda were reduced, whereas the stromal region of the epididymis caput was increased in the B. forficata group, compared with the control group. The testicular tissue was less impaired, considering that all the histological analyses were similar to the control. We believe that B. forficata alcoholic extract in the male genital system showed antioxidant action, especially in the epididymal tissue.  相似文献   

7.
Evolutionary significance of myosin heavy chain heterogeneity in birds   总被引:1,自引:0,他引:1  
This article reviews the complexity, expression, genetics, regulation, function, and evolution of the avian myosin heavy chain (MyHC). The majority of pertinent studies thus far published have focussed on domestic chicken and, to a much lesser extent, Japanese quail. Where possible, information available about wild species has also been incorporated into this review. While studies of additional species might modify current interpretations, existing data suggest that some fundamental properties of myosin proteins and genes in birds are unique among higher vertebrates. We compare the characteristics of myosins in birds to those of mammals, and discuss potential molecular mechanisms and evolutionary forces that may explain how avian MyHCs acquired these properties.  相似文献   

8.
Heat stress is an important influence on the male reproductive organs. Therefore, the effects of heat stress on genes or pathways related to the reproductive system of male mice were experimentally explored in this paper to further determine the effects of heat stimulation on mammals. Herein, models of heat-exposed mouse testicular tissue and heat-excited cells were successfully established. Many scorched vesicles were found after heat excitation of testis supporting cells, testicular mesenchymal (TM4) cells. Western blot, in situ terminal deoxynucleotide transferase dUTP Nick end labeling (TUNEL) and transmission electron microscopy showed that membrane rupture, mitochondrial damage and autophagic vesicles occurred in TM4 cells after thermal excitation. The N-segment fragment of the associated protein shear was increased, and the TUNEL result was positive. In conclusion, thermal excitation induced apoptosis and scorch death in TM4 cells. Thus, the Hippo pathway and apoptosis-related pathway were significantly enriched after heat stimulation in mouse testis, and the scorch death effect in TM4 cells was induced by heat excitation.  相似文献   

9.
Morphologic features may sometimes be interpreted differently by different pathologists. By introducing objective methods in the histological evaluation the subjectivity of the judgement is reduced and a higher degree of consistency achieved. In the present study three linear parameters of nasal epithelial basal cells: the largest transversal nuclear diameter, the sum of the longitudinal and transversal nucleolar axes and the basal cell width, i.e. the width of the attachment face to the basement membrane, were classified by means of three-class rulers. From this classification weighted indices were made which were then given equal weight and transformed, so that when added up their sum, the joint index (Q) to the largest possible extent was consistent with pseudostratified/stratified cuboidal, stratified squamous and dysplastic epithelium when Q ≤ 1, 1 < Q ≤ 2 and Q > 2 respectively. Tested prospectively we found 91% agreement between the morphometric and histological classification. The method presented is extremely simple and rapid to perform, and appears to have diagnostic potential in distinguishing various types of epithelial alterations of the nasal mucosa. The method may also be useful in approaching similar problems in other epithelia.  相似文献   

10.
Accumulation of pollutants in the aquatic system has a high impact on the reproductive physiology of crustaceans. The objective of the present study was to assess the possible histopathological effects of combined chlorpyrifos and cypermethrin (nurocombi) exposure on reproductive tissue in male freshwater crab Paratelphusa jacquemontii using light and electron microscopy. The testis of experimental crabs showed disorganization of testicular lobules, increased inters cellular space, necrosis, and cellular damage in both germinal cells and Sertoli cells. The treated vas deferens exhibited epithelial degeneration, misshaped spermatophores, decline in the number of spermatophores, and dehiscence of spermatophore wall. These clinical manifestations expressed in crabs following the exposure of nurocombi significantly reduce the testicular activity and substantially inhibits the seminal secretions, which ultimately lead to impairment of reproduction.  相似文献   

11.
This paper presents a discussion of the system of the measurement of the gas flow (of air or flue gases) dedicated particularly for use in rectangular ducts with short straight sections and with considerable cross-section dimensions (above 1 m). The measurement is conducted at a necking – the duct inset – with a single-point sensor such as the Prandtl tube. The measuring method may be used in newly designed air and flue gas ducts, as well as in those already in service, such as air conditioning or ventilation systems and power boilers.  相似文献   

12.
Puberty is characterized by psychosomatic alterations, whereas chronic ethanol consumption is associated with morphophysiological changes in the male reproductive system. The purpose of this study was to show the toxic effects on testis and epididymal morphophysiology after ethanol administration during peripuberty. To this end, male Wistar rats were divided into two groups: ethanol (E) group: received a 2 g dose of ethanol/kg in 25% (v/v); and control (C) group: received the same volume of filtered water; both were treated by gavage for 54 days. On the 55th day of the experiment, epididymis, and testis were collected for sperm count, histopathology, mast cell count, and morphometry. The vas deferens was collected for sperm motility analysis. The femur and testicle were used for cytogenetic analysis. Ethanol exposure caused reduction in daily sperm production (DSP) and in sperm motility, multinucleated cells or those having no chromosomal content, and late chromosome migrations. No changes were observed in the number of chromosomes in the mitotic analysis. However, some alterations could be seen in meiocytes at different stages of cell division. Stereological analysis of the epididymis indicated reorganization of its component in the 2A and 5A/B regions. The epididymal cauda had greater recruitment, and both degranulated and full mast cells showed an increase in the initial segment, in the ethanol group. In conclusion, ethanol administration during the pubertal phase affects epididymis and testis in adult rats, as indicated mainly by our new findings related to mast cell number and meiotic impact. Microsc. Res. Tech. 79:541–549, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   

13.
Several data suggest that melatonin may influence avian reproduction by acting at the level of the hypothalamic-hypophisial-gonadal axis, and/or on neural circuits controlling reproductive behaviours. The action of melatonin is exerted through specific receptors whose distribution and pharmacological properties have been extensively investigated. This review will focus on the distribution, sexual dimorphism, and dependence upon the photoperiod of melatonin binding sites in avian species with a special emphasis on Japanese quail. Melatonin receptors are widely distributed in avian brain. They are mostly present in the visual pathways of all the investigated species and in the song controlling nuclei of oscine birds. Sexual dimorphism of melatonin binding sites (higher density in males than in females) was detected in some telencephalic nuclei of songbirds, in the visual pathways, and in the preoptic area of quail. The last region plays a key role in the activation of male quail copulatory behaviour and it hosts a large population of gonadotropin-releasing hormone-containing neurons. Sexual dimorphism of melatonin-binding sites in the above-mentioned regions suggests a differential role for this hormone in the modulation of visual perception, gonadotropin production, and seasonally activated behaviours in male and female quail. Further studies are necessary to understand interrelationships among photic cues, gonadal steroids, density, and sexually dimorphic distribution of melatonin receptors.  相似文献   

14.
Circadian organization and the role of the pineal in birds   总被引:1,自引:0,他引:1  
All organisms exhibit significant daily rhythms in a myriad of functions from molecular levels to the level of the whole organism. Significantly, most of these rhythms will persist under constant conditions, showing that they are driven by an internal circadian clock. In birds the circadian system is composed of several interacting sites, each of which may contain a circadian clock. These sites include the pineal organ, the suprachiasmatic nucleus (SCN) of the hypothalamus, and, in some species, the eyes. Light is the most powerful entraining stimulus for circadian rhythms and, in birds, light can affect the system via three different pathways: the eyes, the pineal, and extraretinal photoreceptors located in the deep brain. Circadian pacemakers in the pineal and in the eyes of some avian species communicate with the hypothalamic pacemakers via the rhythmic synthesis and release of the hormone melatonin. Often the hypothalamic pacemakers are unable to sustain persistent rhythmicity in constant conditions in the absence of periodic melatonin input from the pineal (or eyes). It has also been proposed that pineal pacemakers may be unable to sustain rhythmicity in constant conditions without periodic neural input from the SCN. Significant variation can occur among birds in the relative roles that the pineal, the SCN, and the eyes play within the circadian system; for example, in the house sparrow pacemakers in the pineal play the predominant role, in the pigeon circadian pacemakers in both the pineal and eyes play a significant role, and in Japanese quail ocular pacemakers play the predominant role.  相似文献   

15.
This study investigated the relationship among heat shock protein 70 (HSP70), proliferating cell nuclear antigen (PCNA), and testicular apoptosis during a breeding cycle of Prochilodus argenteus, a neotropical migratory characiform fish of importance in commercial fishery from the São Francisco River basin. A total of 48 (12 fish/sampling) adult males were caught using casting and drifting nets in four samplings from June 2008 to March 2009. Immunohistochemistry, Western blotting, terminal transferase‐mediated dUTP nick‐end labeling (TUNEL), enzyme‐linked immunosorbent assay (ELISA), and caspase‐3 colorimetric assay were assessed in different phases of spermatogenesis. Labeling for HSP70 occurred in spermatogonia (SPGA 18.0±1.5 and SPGB 27.9±1.0 in 100 mm2, respectively) and Sertoli cells in all sampling periods, with higher values in June (resting period) while spermatocytes were labeled in September (maturation period) and December (ripe period). For PCNA, immunoreaction was predominant in spermatogonia in June and September, while primary spermatocytes were labeled mainly in December (18.7±2.0). TUNEL‐positive reaction occurred throughout the sampling periods, and labeling was detected in the nucleus of germ cells in all developmental phases, except spermatozoa. By ELISA, total HSP70 in testis increased significantly from June to December, and decreased in March (regression period), P<0.05. Caspase‐3 activity decreased from June to December and increased in March. Taken together, our results suggest that HSP70 may protect the germ cells from caspase‐3‐dependent apoptosis during testicular activity and, reduction of HSP70 and increase of apoptosis contribute for testicular remodeling after the breeding season in wild populations of P. argenteus in the São Francisco River. Microsc. Res. Tech. 76:350–356, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

16.
A sexually dimorphic nucleus is located in the preoptic area of Japanese quail and plays a key role in the activation of male copulatory behavior. The medial preoptic nucleus (POM) is significantly larger in adult male than in adult female quail. Its volume is steroid-sensitive in adulthood and consequently decreases after castration but is restored to normal levels by a treatment with exogenous testosterone. This volumetric difference appears to result only from a sex difference in the adult hormonal milieu and is not affected by embryonic treatments that permanently modify sexual behavior (no organizational effects). In contrast, some cytoarchitectonic features of the POM such as the size of neurons in the dorso-lateral part of nucleus appear to be irreversibly affected by embryonic steroids. The POM is characterized by the presence of a wide variety of neurotransmitters, neuropeptides, and receptors and can be specifically identified by the presence of a dense cluster of aromatase-immunoreactive cells, by a high density of neurotensin-immunoreactive cells and fibers and by a dense vasotocinergic innervation. Some of these neurochemical markers of the dimorphic nucleus are themselves modulated by steroids. Many of these neurochemical changes appear to play a causal role in the control of male sexual behavior. The quail POM thus represents an excellent model for the analysis of steroid-induced brain plasticity in a behaviorally relevant context.  相似文献   

17.
以某高功耗军用加固计算机热设计为实例,介绍了热设计过程中,加固计算机主板芯片到风道这一传导路径热阻计算的具体方法,对比了军用加固计算机采用单、双风道各自的传导热阻.并用Ice-Pak热分析软件对采用单、双风道的加固计算机主板温度分布进行了仿真计算,通过实践证明了双风道散热形式在高功耗加固计算机中的可实施性和优越性.  相似文献   

18.
以某高功耗军用加固计算机热设计为实例,介绍了热设计过程中,加固计算机主板芯片到风道这一传导路径热阻计算的具体方法,对比了军用加固计算机采用单、双风道各自的传导热阻.并用IcePak热分析软件对采用单、双风道的加固计算机主板温度分布进行了仿真计算,通过实践证明了双风道散热形式在高功耗加固计算机中的可实施性和优越性.  相似文献   

19.
The male reproductive system of Eurydema ventrale Kolenati 1846 is studied morphologically and histologically by using light, scanning and transmission electron microscopes. The reproductive system of the male E.ventrale consists of a pair of testis, a pair of vas deferens, a pair of seminal vesicles, accessory glands, a bulbus ejaculatorius, a pair of ectodermal sacs, and a ductus ejaculatorius. The testicular follicles have three different development zones (growth zone, maturation zone, and differentiation zone). The testes are connected to the seminal vesicles by the vas deferens that is a specialized in sperm storage. Sperm have an elongated head and a tail (flagellum) with an axonema and two mitochondrial derivatives. Vas deferens and seminal vesicles are fine, long, and cylindrical. The seminal vesicle is connected with bulbus ejaculatorius, which is balloon shaped and surrounded with accessory glands. The bulbus ejaculatorius is continuous with ductus ejaculatorius which is connected to the aedeagus. Microsc. Res. Tech. 78:643–653, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   

20.
The human respiratory system consists of the upper and the lower respiratory tracts. Anatomically, the lower respiratory tract consists of the trachea, bronchi, bronchioles (terminal bronchioles and respiratory bronchioles), alveolar duct, alveolar duct sacs, and alveoli. Alveoli are composed of two epithelial cell types, cuboidal alveolar type 2 (AT2) cells that secrete surfactant to prevent alveolar collapse and function as stem cells to regenerate alveolar type 1 (AT1) cells during damage repair, and squamous AT1 cells that cover most of the surface area of the alveoli and mediate gas exchange. Previous studies mainly focused on AT2 cells; this review summarizes the current studies on lung development and property of AT1 cells.  相似文献   

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