Changes in serum enzyme activities after injection of bupivacaine
into the rat tibialis anterior.
Nosaka, Kazunori.
Exercise and Sports Science, Department of Environmental Science,
Yokohama City University, 22-2, Seto, Kanazawa-ku, Yokohama, 236,
Japan
APStracts 3:0171A, 1996.
This study investigated the time course of changes in serum creatine
kinase (CK), aspartate aminotransferase (AST), and alanine
aminotransferase (ALT) activities after intramuscular injection of
bupivacaine into the tibialis anterior (TA) of rats. Morphological
changes in muscle cells, relationships between the amount of increase
in the enzyme activities and the muscle mass damaged, and responses
of serum enzymes to additional injections of BPVC were also examined.
Adult Wistar male rats (24 wk) were placed into one of the four
groups. Group A (n=7) was a control and no injection was applied. 0.5
ml of 0.9 % saline solution was injected into the right TA for Group
B (n=5). 0.5 ml of 0.5% bupivacaine hydrochloride (BPVC) was injected
into the right TA for Group C (n=9), and into both the right and left
TA for Group D (n=9). No increases in CK, AST, and ALT were observed
for Groups A and B. After BPVC injection, Groups C and D showed
significant (p<0.01) increases in serum enzyme activities. CK
peaked 4 hours after BPVC injection, and AST and ALT peaked 12 hours
post- injection, then returned to the baseline by the time when
infiltration of mononuclear cells into the damaged muscle cells
progressed. The amount of enzyme increase was significantly larger
(p<0.01) for Group D compared to Group C. Injection of BPVC into
the right then to the left TA 4 hours later displayed a bipolar
response, and the second injection to the TA 12 weeks after the first
injection resulted in smaller increase in serum enzyme activities. It
appeared that increases in serum enzyme activities reflected muscle
damage, however changes in enzymes occurred in the early stage of
myonecrosis.
Received 3 April 1995; accepted in final form 19 March 1996.
APS Manuscript Number A368-5.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 1 April 96