INVESTIGADORES
BARRANTES Francisco Jose
artículos
Título:
Ultrastructure of Psammobatis exenta (Rajidae) electrocytes and cytochemical localization of acetylcholinesterase, acetylcholine receptor and F-actin
Autor/es:
PRADO FIGUEROA M; VIDAL A; BARRANTES FJ
Revista:
BIOCELL
Editorial:
INST HISTOL EMBRIOL-CONICET
Referencias:
Lugar: Mendoza; Año: 1995 vol. 19 p. 113 - 123
ISSN:
0327-9545
Resumen:
1. The electrocytes from the electric organ of the Patagonian ray P. extenta
are very unusual cells: semicircular in shape, multinucleated and
highly polarized. They have an anterior, concave, innervated face, which
exhibits positive histochemical reactions for acetylcholinesterase and for the nicotinic acetylcholine receptor.
Multiple nerve-endings are covered with Schwann cell projections,
similar to those present in skeletal muscle. Their posterior face is
convex, non-innervated and is in contact with collagen fibres. 2. The
cytoplasm of these electrocytes possesses abundant filamentous actin (F-actin), orderly distributed in the cell and exhibiting intense fluorescence with NBD-phallacidin. The F-actin
is in contact with Z-lines as in muscle, and in contrast with Torpedo
(Kordeli et al., 1986, 1987) and Discopyge (Vidal et al., 1986, 1989a)
electrocytes, where it is confined to the non-innervated face. 3.
Electrocytes of this Rajidae are an ideal model for the study of F-actin
because of the similar embryological origin with skeletal muscle tissue
and also because of the peculiar characteristics of their cytoplasm,
packed full with F-actin. In addition, electric organs could constitute an alternative biological source for the study of the cholinergic synapse.