Groups of pregnant rats were injected with two successive daily doses of 3H-thymidine from gestational day 12 and 13 (E12 + 13) until the day before parturition (E21 + 22) in order to label in their embryos the proliferating precursors of neurons. At 60 days of age the proportion of neurons generated (or no longer labeled) on specific embryonic days was determined quantitatively in 14 nuclei of...

Hair cells, the sensory receptors of auditory and vestibular systems, use a transducer apparatus that renders them remarkably sensitive to mechanical displacement as minute as 1 nm. To study the embryonic development of the transducer apparatus in hair cells of the chick auditory papilla, we examined hair cells that have been labeled with N-(3-triethylammoniumpropyl)-4-(4-(dibutylamino)styryl) ...

We examined the expression of basic helix-loop-helix transcription factors NSCL1 and NSCL2 in the olfactory epithelium (OE) and the vomeronasal organ (VNO) during development. As detected by in situ hybridization, at embryonic day (E) 10 NSCL1 was weakly expressed in the entire olfactory placodes. From E12 to postnatal day (P) 3, NSCL1 was expressed in olfactory receptor neurons (ORNs) and rece...

Comparative embryonic studies are the most effective way to discern phylogenetic changes. To gain insight into the constitution and evolution of mammalian somatosensory thalamic nuclei, we first studied how calbindin (CB) and parvalbumin (PV) immunoreactivities appear during embryonic development in the first-order relaying somatosensory nuclei, i.e., the ventral posteromedial (VPM) and postero...

The Edinger-Westphal nucleus (EW) in birds is responsible for the control of pupil constriction, accommodation, and choroidal blood flow. The activation of EW neurons is mediated by the neurotransmitter glutamate, in large part through AMPA-type glutamate receptors (GluRs), whose behavior varies according to the subunit composition. We investigated the developmental expression of the GluR subun...

1869. [3] Malin M. C. and Edgett K. S. (2000) Science, 290, 1927-1937. [4] Golombek M. P. et al. (2003) JGR, 108, E12. [5] Christensen P. R. (1986) Icarus, 68, 217-

We examined the expression of the neurotrophins (NTFs) and their receptor mRNAs in the rat trigeminal ganglion and the first branchial arch before and at the time of maxillary nerve growth. The maxillary nerve appears first at embryonic day (E)10 and reaches the epithelium of the first branchial arch at E12, as revealed by anti-L1 immunohistochemistry. In situ hybridization demonstrates, that a...