Immunohistochemical studies of the localization of neurons containing the enzyme that synthesizes dopamine, GABA, or gamma-hydroxybutyrate in the rat substantia nigra and striatum.

gamma-Hydroxybutyrate (GHB) is an endogenous metabolite of gamma-aminobutyric acid (GABA), which is synthesized in the neuronal compartment of the central nervous system. This substance possesses several properties that support its role as a neurotransmitter/neuromodulator in brain. In particular, it is synthesized by a specific pathway that transforms GABA into succinic semialdehyde via GABA-T activity; then succinic semialdehyde is converted into GHB by a specific succinic semialdehyde reductase (SSR).

Astrocytes induce several blood-brain barrier properties in non-neural endothelial cells.

The passage of immunocompetent cells across the blood-brain barrier (BBB) is regulated at the level of the cerebral capillaries which have specific morphological and biochemical properties. We have developed and characterized an in vitro model of the BBB using immortalized human endothelial cells (ECV 304) induced by rat astrocytes. In this model, endothelial cells are attached together by continuous intercellular junctions with numerous tight junctions, develop a permeability barrier having a significant transcellular electrical resistance, possess high activities of gamma-glutamyl transpeptidase (gamma-GTP) and express the brain-type glucose transporter 1 (GLUT-1).

Inositol 1,4,5-trisphosphate receptor is located to the inner nuclear membrane vindicating regulation of nuclear calcium signaling by inositol 1,4,5-trisphosphate. Discrete distribution of inositol phosphate receptors to inner and outer nuclear membranes.

Transient rise in nuclear calcium concentration is implicated in the regulation of events controlling gene expression. Mechanism by which calcium is transported to the nucleus is vehemently debated. Inositol 1,4,5-trisphosphate (InsP3) and inositol-1,3,4,5-tetrakisphosphate (InsP4) receptors have been located to the nucleus and their role in nuclear calcium signaling has been proposed.

Membrane retrieval following exocytosis in isolated neurosecretory nerve endings.

In the neurosecretory nerve endings of the neurohypophysis depolarization-induced exocytosis is followed by endocytosis of vacuole-like structures with diameter similar to that of neurosecretory granules. However, it remains unknown whether the membrane of the endocytotic vacuoles is comprised primarily of retrieved secretory granule membrane, plasma membrane or of a mixture of the granule and plasma membrane. In the present paper membrane retrieval following depolarization-induced exocytosis has been studied in isolated neurosecretory nerve endings from the rat neurohypophysis.

An improved method for the preparation of rat cerebellar glomeruli.

Cerebellar glomeruli consist of large portions of the mossy fiber giant terminal, granule cell dendrites and Golgi neuron terminals. By modifying previously reported procedures we have developed a new method for bulk preparation of this polysynaptic complex from rat cerebellum. We obtained well preserved isolated glomeruli of satisfactory purity and homogeneity as indicated by electron microscopy and by determination of appropriate biochemical markers.