ISSN:
1432-0878
Keywords:
Hippocampus
;
Mossy fibers
;
Picrotoxin
;
Ultrastructure
;
Rat (Wistar)
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary Ultrastructural changes in hippocampal granule cells, mossy fibers and mossy fiber boutons were examined following the administration of picrotoxin in adult rats. Generalized seizures occurred within 5–10 min after the intraperitoneal injection of picrotoxin. The electron-microscopic examination of hippocampal tissues from rats that had been perfused with fixative during the seizure revealed that the large dense-core vesicles increased in number and accumulated on the presynaptic membranes of mossy fiber boutons; some of these vesicles appeared to be fused with the membranes, and omega-shaped exocytotic profiles were frequently seen. Furthermore, greatly increased numbers of coated vesicles (60–90 nm in diameter) were observed on the maturing faces of Golgi fields of granule cells. Thus, our study not only indicates an increased incidence of exocytosis of large dense-core vesicles during picrotoxin-induced seizures, but also suggests that these vesicles are replaced in excess from the perikaryon of the granule cell.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00224107
