Developmental changes of keratin expression in chick embryo olfactory epithelium in relation to cellular differentiation and neurogenesis in vivo and in vitro.

Olfactory embryogenesis was studied using an anti-chick keratin antibody on chick embryo sections as well as in vitro. Olfactory placodes form at embryonic day 3 (ED3) in the anterior facial ectoderm and invaginate to form the nasal pits. At ED5, the epidermal ectoderm and respiratory epithelium show the same dense cytokeratin immunoreaction.

Expression of insulin-like growth factor-I (IGF-I) and IGF-II in the avian brain: relationship of in situ hybridization patterns with IGF type 1 receptor expression.

Insulin-like growth factors (IGFs) are expressed in defined spatiotemporal patterns during the development of the mammalian central nervous system (CNS). Since IGF expression in avian species is less well documented, we studied here the expression of IGF-I and IGF-II during chicken CNS development, using in situ hybridization and reverse transcriptase-PCR, and compared the results with the expression of the IGF type 1 receptor (IGF-1R). IGF-II expression started early in embryonic life, shortly after the onset of IGF-1R expression.

Mild kainate toxicity produces selective motoneuron death with marked activation of CA(2+)-permeable AMPA/kainate receptors.

Motoneuron death could be produced by higher sensitivity to excitoxicity during the development and pathological conditions. We report here that in ventral spinal cord cultures mild kainate exposure (12.5 microM, 20 min or 100 microM, 2.

Changes in IGF-1 receptors in the hippocampus of adult rats after long-term adrenalectomy: receptor autoradiography and in situ hybridization histochemistry.

Alteration of insulin-like growth factor-1 (IGF-1) receptor and its mRNA after long-term adrenalectomy (ADX) was studied in the hippocampus by in vitro receptor autoradiography and in situ hybridization histochemistry, respectively. Significantly, decreased levels of IGF-1 receptor and its mRNA was noted in the dentate and CA1-CA4 regions of the hippocampus of the ADX animals, suggesting that the level and expression of IGF-1 receptors in the hippocampus is influenced by adrenal hormones.