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E L Battenberg

Publications and source records attributed to E L Battenberg.

12 recordsLinked to original sources

The hypocretins: hypothalamus-specific peptides with neuroexcitatory activity.

We describe a hypothalamus-specific mRNA that encodes preprohypocretin, the putative precursor of a pair of peptides that share substantial amino acid identities with the gut hormone secretin. The hypocretin (Hcrt) protein products are restricted to neuronal cell bodies of the dorsal and lateral hypothalamic areas. The fibers of these neurons are widespread throughout the posterior hypothalamus and project to multiple targets in other areas, including brainstem and thalamus. Hcrt immunoreactivity is associated with large granular vesicles at synapses. One of the Hcrt peptides was excitatory when applied to cultured, synaptically coupled hypothalamic neurons, but not hippocampal neurons. These observations suggest that the hypocretins function within the CNS as neurotransmitters.

Amino Acid Sequence↗

Four structurally distinct neuron-specific olfactomedin-related glycoproteins produced by differential promoter utilization and alternative mRNA splicing from a single gene.

Four structurally related neuron-specific 1B426b mRNAs, designated AMY, BMY, AMZ, and BMZ, have been isolated from rat brain cDNA libraries. The four mRNAs are related to one another by their shared M region and by two pairs of alternative 5' (A, B) or 3' (Y, Z) regions. All four possible combinations were detected. The four transcripts are derived by differential promoter utilization (to generate A or B 5' ends) and alternative splicing (to generate Y or Z 3' ends) of the primary transcripts of the single D2Sutle gene. All four mRNAs were detected in most brain regions, but were enriched within the cortex and hippocampus. In the pituitary only the two A-type and in the adrenal glands only the two B-type mRNAs were detected. In situ hybridization shows a highly heterogeneous distribution across brain regions, paralleling the Northern blot results and additionally identifying the reactive cells as neurons. The cDNAs encode related glycoproteins of 125, 153, 457, and 485 amino acids, which have been detected immunochemically. The AMZ and BMZ proteins show significant sequence similarity with olfactomedin, an extracellular matrix protein of bullfrog olfactory epithelium, suggesting the possibility of a matrix-related function for these rat glycoproteins in neurons and neurosecretory cells.

Animals↗

1G5: a calmodulin-binding, vesicle-associated, protein kinase-like protein enriched in forebrain neurites.

We have characterized cDNA clones of 1G5, an mRNA highly enriched in the mammalian forebrain that encodes a 504-residue protein found in association with perikaryal membranes and neurites. The protein, which accumulates predominantly postnatally, is associated with vesicles in both axons and dendrites. The sequence of the 1G5 protein highly resembles those of protein kinases with serine/threonine specificity; however, although most residues universally conserved among protein kinases are present, a few signature residues are absent from the 1G5 protein. Furthermore, although recombinant 1G5 protein binds calmodulin in the presence of calcium, it lacks kinase activity with a sample substrate.

Amino Acid Sequence↗

Viral infection of neurons can depress neurotransmitter mRNA levels without histologic injury.

Neonatal mice inoculated with lymphocytic choriomeningitis virus (LCMV) have non-lytic persistent neuronal infection and disturbed behavior. We now show that LCMV replicates in neurons containing the neurotransmitter somatostatin without morphologic evidence of injury and that persistent neuronal LCMV infection in mice is attended by a decrease in brain levels of somatostatin mRNA. Brain levels of mRNA for another neurotransmitter peptide, cholecystokinin, are not decreased. These data are the first to localize a virus to a specific neurotransmitter-containing cell during in vivo infection and suggest that persistent viral infections could cause neurologic or psychiatric diseases through selective effects on brain levels of neurotransmitter mRNAs.

Animals↗

Immunocytochemical mapping of 1B236, a brain-specific neuronal polypeptide deduced from the sequence of a cloned mRNA.

The 318-amino acid, carboxy-terminal sequence of the putative brain-specific polypeptide 1B236 was deduced from the nucleotide sequence of its cloned brain-specific mRNA. Antisera raised against selected synthetic peptide fragments of this protein were used to map the cellular location of the presumptive gene product in the brains of normal or colchicine-pretreated adult rats. Antisera directed against any of three C-terminally located, but nonoverlapping, nonhomologous, synthetic peptide segments (P5, P6, or P7) produced virtually identical maps of intensely immunoreactive neuropil staining. The immunoreactivity was distributed heterogeneously and was most pronounced within olfactory, somatosensory, and limbic systems, and was more modest in certain motor and auditory structures. In colchicine-pretreated rats, large, multipolar perikarya were observed within the amygdala, caudate-putamen, cingulate, parietal, and piriform cortices, as well as in particular diencephalic and pontine nuclei. Smaller immunoreactive neurons with more limited dendritic extensions were observed in the olfactory bulb, the cerebellar cortex, and the dorsal horn and intermediolateral cell columns of the spinal cord. No immunoreactivity was observed in visceral structures innervated by the autonomic nervous system or in non-neural tissues. In addition to the virtually superimposable maps produced by antisera to all three synthetic fragments selected from the C-terminus of 1B236, some uniquely reactive sites were seen. Antisera to the most N-terminal of the three synthetic immunogens (P5) were reactive with neurons of the medial trapezoid nucleus and in nerve terminals surrounding the deep cerebellar nuclei. Antisera against the most C-terminal synthetic immunogen (P7) were reactive with neurons of the paraventricular and supraoptic hypothalamic nuclei. These data demonstrate that the 1B236 protein is located within selected neuronal elements within functionally related cellular circuits established more formally by other methods. Our data show that protein 1B236-immunoreactive cells share at least the expression of this protein and suggest that these cells may also be related epigenetically or evolutionarily. These data, together with other subcellular, ultrastructural, and electrophysiological properties of 1B236, suggest that this protein could be considered as a prohormone capable of yielding several final candidate transmitter products.

Animals↗

Monoclonal antibodies against vasoactive intestinal polypeptide: studies of structure and related antigens.

Hybridomas secreting monoclonal anti-vasoactive intestinal polypeptide (VIP) antibodies were constructed from spleen cells sensitized to VIP in vitro. The secreted antibodies were characterized by binding to VIP in indirect radioimmunoassays and enzyme-linked immunosorbent assays. Two monoclonal antibodies, characterized for their binding activities with synthetic fragments of VIP, were found to bind different sites on the VIP molecule. These monoclonal antibodies may recognize tertiary structures of the VIP. A search was conducted for antigens recognized by the monoclonal antibodies in brain: brain proteins separated on polyacrylamide gels were electroblotted onto nitrocellulose filters and were reacted first with the mouse antibody and then with goat anti-mouse immunoglobulin coupled to horseradish peroxidase as a means of detection. The monoclonal antibodies were found to react with a protein of molecular weight 60,000, which was also recognized by polyclonal antibodies, although the latter reacted with a number of additional proteins. The relationship of the protein of molecular weight 60,000 to VIP is discussed.

Adrenal Gland Neoplasms↗

A fluorescent histochemical study of changes in noradrenergic neurons following experimental cerebral infarction in the rat.

Following surgical ligation of the middle cerebral artery in the rat, central catecholamine containing neurons were studied using the glyoxylic acid histochemical technique. By 5 days after the ischemic lesion, the density of fluorescent varicosities decreased in both uninjured cerebral cortex and the cerebellar cortex and the intensity of fluorescence of somata in the ipsilateral and contralateral locus coeruleus decreased as compared with controls. At 20 days afer lesioning, catecholamine containing neurons looked normal under fluorescence microscopic examination, except fine varicose fluorescent axons were present for the first time among the cellular debris of the lesion and appeared to have sprouted into the lesion site. However, by 40 days after surgery, there was a marked increase in the density of fluorescent varicosities in the uninjured ipsilateral cerebral cortex, in the contralateral cerebral cortex, and in the cerebellum. These observations confirm the view that an ischemic cortical lesion can lead to profound changes in cetecholamine containing neurons in distant areas of the brain which are uninjured by the local infarction.

Animals↗

A rapid, simple and more sensitive method for the demonstration of central catecholamine-containing neurons and axons by glyoxylic acid induced fluorescence: I. Specificity.

Perfusion fixation with a mixture of paraformaldehyde and glyoxylic acid facilitates the histochemical demonstration of catecholamine-containing brain neurons. With this fixation, sections can be cut reproducibly with a cryostat and the fluorophore developed by immersion in glyoxylic acid without freeze-drying. Large sections of brain can be examined by fluorescence microscopy within 1 hour of fixation or stored for later examination. The properties of the fluorophore and the location of the fluorescent elements is identical with the neurons and terminal arborizations demonstrated by previous glyoxylic acid methods. Monoamine oxidase inhibition before fixation results in moderately increased fluorescence of terminals and perikarya, while all glyoxylic acid induced fluorescence is abolished by pre-treatment with reserpine. The rapidity and simplicity of this technique may make fluorescence histochemistry of central catecholamine pathways more accessible to psychopharmacologists.

Animals↗