Author/Editor | Trinkaus, M; Pregelj, P; Trkov, S; Sketelj, J | |
Title | Neural regulation of acetylcholinesterase-associated collagen Q in rat skeletal muscles | |
Type | članek | |
Source | J Neurochem | |
Vol. and No. | Letnik 105 | |
Publication year | 2008 | |
Volume | str. 2535-44 | |
Language | eng | |
Abstract | Acetylcholinesterase-associated collagen Q is expressed also outside of neuromuscular junctions in the slow soleus muscle, but not in fast muscles. We examined the nerve dependence of muscle collagen Q expression and mechanisms responsible for these differences. Denervation decreased extrajunctional collagen Q mRNA levels in the soleus muscles and junctional levels in fast sternomastoid muscles to about one third. Cross-innervation of denervated soleus muscles by a fast muscle nerve, or electrical stimulation by 'fast' impulse pattern, reduced their extrajunctional collagen Q mRNA levels by 70-80%. In contrast, stimulation of fast muscles by 'slow' impulse pattern had no effect on collagen Q expression. Calcineurin inhibitors tacrolimus and cyclosporin A decreased collagen Q mRNA levels in the soleus muscles to about 35%, but did not affect collagen Q expression in denervated soleus muscles or the junctional expression in fast muscles. Therefore, high extrajunctional expression of collagen Q in the soleus muscle is maintained by its tonic nerve-induced activation pattern via the activated Ca(2+)-calcineurin signaling pathway. The extrajunctional collagen Q expression in fast muscles is independent of muscle activation pattern and seems irreversibly suppressed. The junctional expression of collagen Q in fast muscles is partly nerve-dependent, but does not encompass the Ca(2+)-calcineurin signaling pathway. | |
Descriptors | ACETYLCHOLINESTERASE COLLAGEN MUSCLE, SKELETAL NEUROMUSCULAR JUNCTION MUSCLE DENERVATION RNA, MESSENGER ELECTRIC STIMULATION TACROLIMUS CYCLOSPORINE POLYMERASE CHAIN REACTION RATS |