The loss of muscle weight in the soleus (
SOL) and extensor digitorum longus (EDL) muscles was compared after
denervation and in the course of reflex
muscle atrophy induced by unilateral fracture of metatarsal bones of the paw and local injection of 0.02 ml
turpentine oil subcutaneously. This so-called reflex
atrophy is significantly greater after 3 days than that after
denervation. Seven days after the nociceptive stimulus, reflex and
denervation atrophy are grossly similar in both muscles. This also applies in case that the nociceptive stimulus had been repeated on the third day. The EDL:
SOL enzyme activities of energy supply metabolism reflect the differences between a glycolytic-aerobic (EDL) and predominantly aerobic type (
SOL) of muscle. No consistent changes were found in either type of
atrophy after 3 days. In 7 days'
denervation, the activity of hydroxyacetyl-
CoA-
dehydrogenase (HOADH) and
citrate synthase (CS) was decreased in the
SOL, while
glycerolphosphate:
NAD dehydrogenase (GPDH) was enhanced. In the EDL, the activity of
triosephosphate dehydrogenase (TPDH), GPDH,
malate dehydrogenase (MDH), CS and HOADH was decreased.
Acid phosphatase (AcP) was greatly increased in both muscles. Seven days after application of the nociceptive stimulus, all
enzyme activities were altered in a grossly analogous manner as after
denervation.