This article is a US Government work and, as such, is in the public domain in the United States of America.
Expression of Trk receptors in the oculomotor system of the adult cat†
Article first published online: 23 APR 2004
Published 2004 Wiley-Liss, Inc.
Journal of Comparative Neurology
Volume 473, Issue 4, pages 538–552, 7 June 2004
How to Cite
Benítez-Temiño, B., Morcuende, S., Mentis, G. Z., de la Cruz, R. R. and Pastor, Á. M. (2004), Expression of Trk receptors in the oculomotor system of the adult cat. J. Comp. Neurol., 473: 538–552. doi: 10.1002/cne.20095
- Issue published online: 23 APR 2004
- Article first published online: 23 APR 2004
- Manuscript Accepted: 6 JAN 2004
- Manuscript Revised: 30 DEC 2003
- Manuscript Received: 30 OCT 2003
- Ministerio de Ciencia y Tecnología-Fondo Europeo de Desarrollo Regional (MCYT-FEDER). Grant Number: BF12003-01024
- Fundación Eugenio Rodríguez Pascual
- Fondo de Investigacion Sanitaria (FIS) in Spain. Grant Number: 01/0193
- abducens nucleus;
- tyrosin protein kinases
We examined the expression of the three Trk receptors for neurotrophins (TrkA, TrkB, and TrkC) in the extraocular motor nuclei of the adult cat by using antibodies directed against the full-Trk proteins in combination with horseradish peroxidase retrograde tracing. The three receptors were present in all neuronal populations investigated, including abducens motoneurons and internuclear neurons, medial rectus motoneurons of the oculomotor nucleus, and trochlear motoneurons. They were also present in the vestibular and prepositus hypoglossi nuclei. TrkA, TrkB, and TrkC immunopositive cells were found in similar percentages in the oculomotor and in the trochlear nuclei. In the abducens nucleus, however, a significantly higher percentage of cells expressed TrkB than the other two receptors, among both motoneurons (81.8%) and internuclear neurons (88.4%). The percentages obtained for the three Trk receptors in identified neuronal populations pointed to the colocalization of two or three receptors in a large number of cells. We used confocal microscopy to elucidate the subcellular location of Trk receptors. In this case, abducens motoneurons and internuclear neurons were identified with antibodies against choline acetyltransferase and calretinin, respectively. We found a different pattern of staining for each neurotrophin receptor, suggesting the possibility that each receptor and its cognate ligand may use a different route for cellular signaling. Therefore, the expression of Trk receptors in oculomotor, trochlear, and abducens motoneurons, as well as abducens internuclear neurons, suggests that their associated neurotrophins may exert an influence on the normal operation of the oculomotor circuitry. The presence of multiple Trk receptors on individual cells indicates that they likely act in concert with each other to regulate distinct functions. J. Comp. Neurol. 473:538–552, 2004. Published 2004 Wiley-Liss, Inc.