Author/Editor     Donoghue, Pamela; Ribarič, Samo; Moran, Brendan; Čebašek, Vita; Eržen, Ida; Ohlendieck, Kay
Title     Early effects of denervation on Ca2+-handling proteins in skeletal muscle
Type     članek
Source     Int J Mol Med
Vol. and No.     Letnik 13
Publication year     2004
Volume     str. 767-72
Language     eng
Abstract     The adaptive response of skeletal muscle fibres dcpcnds on a variety of biological factors including loading conditions and neuromuscular activity. An extreme type of atrophy-inducing change in contractile activity is represented by the physical disconnection between the motor nerve and its respective fibre unit. Since fibre type alterations have a striking effect on the Ca2+-regulatory apparatus, we havc investigated the fate of a key Ca2+-pump and essential Caz'binding proteins in extcnsor digitorum longus spccimens two weeks after nerve crush or complete denervation. In contrast to increased levels of sarcalumenin, immunoblotting revealed that the expression of the fast SERCAI Caz+-ATPase isoform is drastically decreased and fast calsequestrin is slightly reduced. Analysis of myosin heavy chain isoforms agreed with this result and showed a fast-to-slow fibre type shifting process Pollowing denervation. Hence, changes in muscle activity appcar to have a profound effect on the abundance and isoform expression pattern of Ca2+-handling elements.
Descriptors     MUSCLE, SKELETAL
MEMBRANE PROTEINS
MUSCLE CONTRACTION
CALCIUM
CA(2+)-TRANSPORTING ATPASE
RATS, WISTAR
SCIATIC NERVE
NERVE CRUSH
MYOSIN HEAVY CHAINS
MUSCLE FIBERS, SLOW-TWITCH
MUSCLE FIBERS, FAST-TWITCH
MUSCLE DENERVATION