Working capacity and expression of myosin heavy chain isoforms in skeletal muscle of chronic alcoholic men without liver disease after 1 day and 4 weeks of alcohol abstinence.
1. The aim of this study was to examine the effect of chronic alcohol ingestion on working capacity and on the expression of myosin heavy chain isoforms in fibre types of human skeletal muscle. 2. Six alcoholic men having drunk more than 240 g of alcohol/day for more than 10 years underwent a test for working capacity and a muscle biopsy on the first day of alcohol abstinence (test 1) and again after 4 weeks of abstinence (test 2). The biopsies were analysed using histochemical, immunochemical and gel-electrophoretic techniques, and the results were compared with those from eight age-matched non-alcoholic control subjects. 3. The area of type IIB muscle fibres was decreased by 33% in the alcoholic patients compared with normal control subjects at both test 1 and test 2. The area of type IIA fibres was lower (13%) in alcoholic patients at test 1 than in the control group, and increased to the normal level at test 2. 4. The relative proportion of fibres expressing only myosin heavy chain type IIB isoforms was one-third of normal in the alcoholic patients at both tests 1 and 2. The relative proportion of fibres expressing only myosin heavy chain type IIA isoforms was the same in alcoholic patients at test 1 and in normal control subjects, but increased by 25% between test 1 and 2 in the alcoholic group.(ABSTRACT TRUNCATED AT 250 WORDS)
Sestoft
L
L
Department of Medicine F, Gentofte Hospital, Hellerup, Denmark.
Iversen
P
P
Nordgaard
I
I
Amris
S
S
Joen
T
T
Overgaard
O
O
Klitgaard
H
H
D000328:Adult; D000437:Alcoholism / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology*; D002908:Chronic Disease; D006801:Humans; D008297:Male; D008875:Middle Aged; D009132:Muscles / Q000201:enzymology* / Q000473:pathology / Q000503:physiopathology*; D009218:Myosins / Q000378:metabolism*; D005082:Physical Exertion / Q000502:physiology*; D013997:Time Factors
D009218:Myosins