Autoradiographic localization of [3H]thiocolchicoside binding sites in the rat brain and spinal cord.

Thiocolchicoside is used in humans as a myorelaxant drug with anti-inflammatory and analgesic activity. Recently we established the experimental conditions that allowed the identification of [3H]thiocolchicoside binding sites in synaptic membranes of rat spinal cord and cerebral cortex. The pharmacological characterization of these sites indicated that GABA and several of its agonists and antagonists, as well as strychnine, were able to interact with [3H]thiocolchicoside binding in a dose-dependent manner and with different affinities.

[Signaling pathways regulating the expression of proteases during tumor progression].

Deregulation of several signaling pathways have been found to be critical for the development of different types of tumors, both in transgenic and spontaneous models. The role of proteases and adhesion molecules during the early stages of tumor progression induced by oncogenes in epithelial and mesenchymal tumors has remained relatively unexplored. This review summarizes recent work showing that different but overlapping signaling effector modules (PKC, v-Ras-RalA-PLD1 or v-Src-RalA-PLD1) induce changes in the production of proteases (uPA and MMPs) and adhesion molecules (fibronectin, CD44, beta 1-integrin) in normal epithelial or mesenchymal cell lines, associated with tumor development in vivo.

The time of tumor cell division and death depends on the site of growth.

We show here, for the first time, in two very different murine tumors, a mammary one (ectoderm) and a lung one (endoderm), that: tumors have day/night differences of spontaneous apoptosis additional to the well-known circadian rhythm of mitosis. The times of maximal and minimal mitosis and apoptosis changed for a tumor cell line when growing in different organs (as metastasis) or anatomical sites. Both tumor lines, have identical circadian curves when growing in a specific organ or anatomical site.

Long-lasting behavioral alterations following a hypoxic/ischemic brain injury in neonatal rats.

The characterization of motor and cognitive dysfunctions following a neonatal ischemic injury is a prerequisite to investigate putative pharmacological interventions. To this end, in the present study, we evaluated the long-lasting behavioral alterations occurring after a hypoxic/ischemic injury obtained by the combination of monolateral carotid ligation and exposure to 8% oxygen for 3 h in 7-day-old rats. These animals show a different degree of damage in the side ipsilateral to the occluded artery.

K562 erythroid and HL60 macrophage differentiation downregulates polycystin, a large membrane-associated protein.

Polycystin, the PKD1 gene product mutated in autosomal dominant polycystic kidney disease, is a large membrane protein which is important in the differentiation of epithelial tubular structure. Furthermore, PKD1 mRNA is expressed in various tissues and in neoplastic cell lines particularly, suggesting that polycystin might be involved in differentiation and/or proliferation of other cell types. Therefore, in order to investigate such a possible role, polyclonal antibodies against a recombinant polycystin peptide were raised and used to study polycystin expression in human leukemia cell lines committed to differentiation.