Biomaterial Database

Exocytosis of cortical granules from activated oocytes of the toad, Bufo arenarum. 1984

M I Gómez, and R C Santolaya, and M O Cabada

Observation of the cortical region of oocytes of Bufo arenarum by transmission electron microscopy reveals modifications on their surface and in the contents of the cortical granules (CG) during activation. In non-activated oocytes only amorphous cortical granules (ACG) can be observed. Activated oocytes display ACG, intermediate cortical granules containing both amorphous and membranous material (ICG), and a third type containing only membranous material (MCG). During exocytosis, CG release their contents into the perivitelline space, where the amorphous and membranous materials are found. The three types of CG found during oocyte activation suggest transformation of ACG to MCG and indicate that the different components of the cortical granules, when released into the perivitelline space, might play different roles in prevention of polyspermy.

UI	MeSH Term	Description	Entries
D008854	Microscopy, Electron	Microscopy using an electron beam, instead of light, to visualize the sample, thereby allowing much greater magnification. The interactions of ELECTRONS with specimens are used to provide information about the fine structure of that specimen. In TRANSMISSION ELECTRON MICROSCOPY the reactions of the electrons that are transmitted through the specimen are imaged. In SCANNING ELECTRON MICROSCOPY an electron beam falls at a non-normal angle on the specimen and the image is derived from the reactions occurring above the plane of the specimen.	Electron Microscopy
D009865	Oocytes	Female germ cells derived from OOGONIA and termed OOCYTES when they enter MEIOSIS. The primary oocytes begin meiosis but are arrested at the diplotene state until OVULATION at PUBERTY to give rise to haploid secondary oocytes or ova (OVUM).	Ovocytes,Oocyte,Ovocyte
D002025	Bufonidae	The family of true toads belonging to the order Anura. The genera include Bufo, Ansonia, Nectophrynoides, and Atelopus.	Bufo,Toads, True,Bufos,Toad, True,True Toad,True Toads
D003594	Cytoplasmic Granules	Condensed areas of cellular material that may be bounded by a membrane.	Cytoplasmic Granule,Granule, Cytoplasmic,Granules, Cytoplasmic
D005089	Exocytosis	Cellular release of material within membrane-limited vesicles by fusion of the vesicles with the CELL MEMBRANE.
D005260	Female		Females
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia