Cholinergic growth factor from skeletal muscle elevated following denervation.
ABSTRACT The effect of skeletal muscle extracts upon cholinergic neuron in vitro survival was investigated. All muscle soluble protein extracts elicited survival of neurons above that of neurons alone in culture and were found to be active below a protein concentration of 1.0 mg/ml. However, skeletal muscle which had been previously denervated, was found to contain higher amounts of survival activity than innervated muscle extracts. This elevation of survival activity was greatest within the first 7 days post-denervation, but subsequently declined towards the innervated level.
- Archives of Physiology and Biochemistry 08/1998; 106(3):161-202.
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ABSTRACT: The expression and content of calcitonin gene-related peptide (CGRP) and secretogranin II (SgII) in adult rat motor neurons were examined by in situ hybridization, Northern blot analysis, and immunocytochemistry. Normal motor nerve terminals did not contain detectable CGRP or SgII. Ten to 15 days after a peripheral nerve crush about 80% of the motor nerve terminals reinnervating the soleus (SOL) muscle contained detectable CGRP but no SgII. Thereafter, the percentage of CGRP-positive terminals declined towards zero. In the spinal cord, CGRP expression was higher than normal 1 d after a sciatic nerve crush and increased during the next few days. No increase in SgII expression was observed. Nerve blocks by tetrodotoxin (TTX) and botulinum toxin (BoTX) increased CGRP content and expression in motor neurons but had no effect on SgII. After 10 d of BoTX treatment and 33 d of TTX treatment (the longest time points studied), more than 90% of the motor nerve terminals stained for CGRP. The density of large dense core vesicles (LDCVs) was also higher than normal in such terminals. Some increase in CGRP content and expression occurred in the nontreated side. In a group of rats, the peroneal nerve was stimulated electrically with brief, intermittent pulse trains at 100 Hz. The stimulation was applied below a TTX block that had started 7 or 19 d earlier. One minute of such stimulation was sufficient to remove CGRP from most of the terminals.(ABSTRACT TRUNCATED AT 250 WORDS)Journal of Neuroscience 02/1995; 15(1 Pt 2):520-8. · 6.91 Impact Factor
- Annals of the New York Academy of Sciences 12/2006; 495(1):378 - 395. · 4.38 Impact Factor