scholarly journals Effects of Ovarian Extract on the Growth of Ovarian Wall Cells from Kuruma Prawn

1997 ◽  
Vol 63 (6) ◽  
pp. 1042-1043
Author(s):  
Isao Yano ◽  
Hiroki Yotsuhashi
Keyword(s):  
Ovarian Wall

scholarly journals The Bdkrb2 gene family provides a novel view of viviparity adaptation in Sebastes schlegelii

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jingjing Niu ◽  
Weihao Song ◽  
Rui Li ◽  
Haiyang Yu ◽  
Jian Guan ◽  
...  
Keyword(s):  
Protein Structure ◽  
Vascular System ◽  
Critical Role ◽  
Future Research ◽  
Breeding Cycle ◽  
Exterior Surface ◽  
Black Rockfish ◽  
Vascular Regulation ◽  
Sebastes Schlegelii ◽  
Ovarian Wall

Abstract Background Black rockfish (Sebastes schlegelii) is a viviparous teleost. We proposed that the rockfish ovarian wall had a similar function to the uterus of mammals previously. In the present study, the well-developed vascular system was observed in the ovarian wall and the exterior surface of the egg membrane. In gestation, adaptation of the ovary vasculature to the rising needs of the embryos occurs through both vasodilation and neovascularization. Bdkrb2, encoding a receptor for bradykinin, plays a critical role in the control of vasodilatation by regulating nitric oxide production. Results Eight Bdkrb2 genes were identified in the black rockfish genome. These genes were located on chromosome 14, which are arranged in a tandem array, forming a gene cluster spanning 50 kb. Protein structure prediction, phylogenetic analysis, and transcriptome analysis showed that eight Bdkrb2 genes evolved two kinds of protein structure and three types of tissue expression pattern. Overexpression of two Bdkrb2 genes in zebrafish indicated a role of them in blood vessel formation or remodeling, which is an important procedure for the viviparous rockfish getting prepared for fertilization and embryos implantation. Conclusions Our study characterizes eight Bdrkb2 genes in the black rockfish, which may contribute to preparation for fertilization and embryo implantation. This research provides a novel view of viviparity adaptation and lays the groundwork for future research into vascular regulation of ovarian tissue in the breeding cycle in black rockfish.

Comparative morpho-anatomical studies of the female gonoduct within the Pratylenchidae (Nematoda: Tylenchina)

Nematology ◽  
2003 ◽  
Vol 5 (2) ◽  
pp. 293-306 ◽  
Author(s):  
Gaëtan Borgonie ◽  
Wim Bert ◽  
Ruben Van Gansbeke ◽  
Etienne Geraert ◽  
Myriam Claeys
Keyword(s):  
Electron Microscopy ◽  
Germ Cells ◽  
The Other ◽  
Radopholus Similis ◽  
Cell Extension ◽  
Anatomical Studies ◽  
Transmission Electron ◽  
Wall Cell ◽  
Ovarian Wall ◽  
Nacobbus Aberrans

AbstractThe cellular morphology of the gonoduct of six Pratylenchus species, three Pratylenchoides species, Radopholus similis, Zygotylenchus guevarai, Hirschmanniella loofi and Nacobbus aberrans was revealed by dissection and light microscopy. Except for Nacobbus aberrans, all studied species show an overall similarity in gonoduct construction, i.e., an ovary often ending with a ring of cells, an oviduct formed from two rows of four cells and a 12-celled spermatheca followed by a tricolumella containing 16-24 cells. Pratylenchoides magnicauda and Z. guevarai did not diverge from the other Pratylenchidae in this respect, although their gonoduct differs from that of Amplimerlinius and Meloidogyne, both formerly postulated as related genera. The spermatheca structure observed in N. aberrans has not been reported elsewhere in the Nematoda, although the uterus is similar to that reported within the Heteroderinae and Meloidogyninae and the uterus comprises more than 300 cells, enlarging from a tricolumella to a polycolumella. Transmission electron microscopy of Z. guevarai revealed details of the cytoplasmatic contact between epithelial cells and the germ cells; a finger-like ovarian wall cell extension was found penetrating the oocyte. The oviduct lacks a preformed lumen and comprises eight cells with highly plicated cell membranes. The spermatheca is constructed from flattened wall cells and is followed by columnar uterus cells where evidence of eggshell formation was demonstrated.

scholarly journals MECHANISM OF STARFISH SPAWNING. IV. TENSION GENERATION IN THE OVARIAN WALL BY 1-METHYLADENINE AT THE TIME OF SPAWNING

1981 ◽  
Vol 161 (1) ◽  
pp. 172-179 ◽  
Author(s):  
HIROKO SHIRAI ◽  
YASUAKI YOSHIMOTO ◽  
HARUO KANATANI
Keyword(s):  
Ovarian Wall ◽  
Tension Generation

Gametogenesis in capelin, Mallotus villosus (Müller), in the northwest Atlantic Ocean

2003 ◽  
Vol 81 (9) ◽  
pp. 1511-1523 ◽  
Author(s):  
S R Flynn ◽  
M P.M Burton
Keyword(s):  
Atlantic Ocean ◽  
Reproductive Biology ◽  
Mallotus Villosus ◽  
Northwest Atlantic ◽  
Important Prey ◽  
Resource Managers ◽  
Capelin Mallotus Villosus ◽  
Ovarian Wall ◽  
History Of ◽  
Post Spawning

Capelin (Mallotus villosus) can be regarded as the most important prey item in the northwest Atlantic Ocean. The health and availability of this species are of fundamental importance for the successful growth and reproduction of many other fishes, whales, and birds. In spite of the clear need to understand this species, the life history of the capelin, especially its reproductive biology, is not well understood. This study substantially improves our knowledge of the reproductive biology of capelin and should be of particular interest to resource managers and administrators. Capelin gonads were analysed over three successive seasons using fish collected during beach spawning (June and July 1993, July 1994, July 1995) or trawled between spawnings, with 11 separate samples (fall, winter, and spring from October 1993 to June 1995). Few immature fish were collected in the trawls; 13/130 (10%) males and 3/150 (2%) females. No recovering (postspawning) males were found in the trawls, but 8/150 (5.3%) recovering females were identified on the basis of large residual oocytes (ovulated or unovulated) and (or) (in the fall) a thicker ovarian wall. Recovering females were identified as late as 10 months post spawning on the basis of residual oocytes. The essential semelparity of males was supported by a lack of apparent spermatogonia during advanced spermatogenesis, whereas the females' capacity to spawn in a subsequent year (iteroparity) was confirmed by the presence of small nonvitellogenic oocytes when other cells were in late oogenesis, in addition to the identification of recovering fish. Oocytes were separable into four stages (potential year classes) and changes occurred in all oocyte stages throughout the cycle of oogenesis. Gametogenesis was more advanced in longer fish, indicating that larger fish spawn earlier than smaller fish.

Micro Structure Analysis of the Ovaries of Common Carp, Cyprinus Carpio L. Inhabiting a Polluted Reservoir, Umiam in Meghalaya, India

2014 ◽  
Vol 20 (5) ◽  
pp. 1404-1410 ◽  
Author(s):  
Bashida Massar ◽  
Sudip Dey ◽  
Karabi Dutta
Keyword(s):  
Electron Microscopy ◽  
Cyprinus Carpio ◽  
Structural Damage ◽  
Histological Analysis ◽  
Fresh Water Fish ◽  
Micro Structure ◽  
Common Carp Cyprinus Carpio ◽  
Transmission Electron ◽  
Water Fish ◽  
Ovarian Wall

AbstractThe study uses microscopy to analyze damage caused to the ovaries of a fresh water fish, Cyprinus carpio L., owing to its exposure to municipal wastes in a polluted reservoir, Umiam in Meghalaya, India. Histological analysis of the ovary showed atretic oocytes, detached ovarian wall, detached follicular linings, and necrosis of nuclei. Scanning electron microscopy revealed deformed oocytes with a rough and distorted surface. Transmission electron microscopy showed a poorly developed chorion, presence of relatively less electron-dense materials as compared with control, multinucleation in some cells surrounding the oocytes, and distorted and condensed mitochondria. The importance of microscopy in its different forms in analyzing histological, surface microstructural and fine structural damage to fish ovaries in response to environmental pollution owing to municipal wastes and city garbage is discussed with the help of available literature.

Fine Structure of Oogenesis in the Snail Tarebia Granifera (Melaniidae)

1977 ◽  
Vol 35 ◽  
pp. 610-611
Author(s):  
Michael T. Matthes ◽  
Robert V. Blystone
Keyword(s):  
Osmium Tetroxide ◽  
Ovarian Tissue ◽  
Uranyl Acetate ◽  
Early Prophase ◽  
Sodium Cacodylate ◽  
En Bloc ◽  
Late Prophase ◽  
Ovarian Wall ◽  
Fresh Water Snail ◽  
Tarebia Granifera

The ovary of the fresh-water snail, Tarebia granifera, is found in the caudal upper whorls of the shell. Careful dissection was required to separate the ovary from the digestive gland which shared a common epithelial covering with the ovary. The ovarian tissue was fixed in sodium cacodylate buffered 3% glutaraldehyde, post-fixed in 1% osmium tetroxide, en bloc stained with 0.5% uranyl acetate, dehydrated, and embedded in Epon-Araldite plastic.This study indicated that oocytes of T. granifera were found only in prophase stages of maturation along the length of the ovarian tube. A similar observation has been documented for the closely related snail Melanoides. The T. granifera oocytes were situated in the ovary in such a way that the immature early prophase oocytes were found near the outer ovarian wall and the more mature late prophase oocytes were seen developing toward the center of the ovarian tubular structure.

Extrafollicular mediation of oocyte maturation by radial nerve factor in starfish Pisaster ochraceus

Zygote ◽  
2000 ◽  
Vol 8 (4) ◽  
pp. 359-368 ◽  
Author(s):  
Allen W. Schuetz
Keyword(s):  
Oocyte Maturation ◽  
Radial Nerve ◽  
Actinomycin D ◽  
Ovarian Tissue ◽  
Germinal Vesicle ◽  
Follicle Cells ◽  
Pisaster Ochraceus ◽  
Ovarian Wall

In starfish ovaries follicle cells that envelop each oocyte are thought to mediate the production of a maturation inducing substance (MIS), identified as 1-methyladenine, that induces maturation and spawning of oocytes after exposure to a gonadotropic substance secreted by the radial nerve (RNF). Studies were carried out to assess the possible role of extrafollicular cells within the ovarian wall in mediating this signal transduction process in the ovary of Pisaster ochraceus. Oocyte maturation and spawning occurred following the addition of RNF to intact ovarian tissue in vitro whereas no maturation occurred following the addition of RNF to germinal vesicle (GV) oocytes or GV oocytes surrounded by follicle cells. In contrast, oocyte maturation occurred when small ovarian wall fragments, lacking mature follicles, were incubated with GV oocytes and RNF. Neither actinomycin D nor cycloheximide altered RNF induction of oocyte maturation in the presence of the ovarian wall tissue whereas preheating (boiling water for 5 min) the tissue obliterated its response to RNF. Non-ovarian tissues failed to produce MIS in response to RNF. Results suggest that ovarian components other than the follicle cells that envelop fully grown immature oocyte are responsive to RNF and represent a significant and previously unrecognised intra-ovarian source of MIS.

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