Avtor/Urednik     Tekavčič, M
Naslov     Korelacija med tipom težke verige miozina in energetsko presnovo v mišičnem vlaknu podgane
Prevedeni naslov     Correlation between myosin heavy chain isoforms and prevailing metabolic pathways in rat muscle fibres
Tip     članek
Vir     Med Razgl
Vol. in št.     Letnik 34, št. 4
Leto izdaje     1995
Obseg     str. 431-7
Jezik     slo
Abstrakt     In the present research we tried to prove, that specific myosin heavy chain is related to a prevalent metabolic type and that activities of succinate-dehydrogenase and a glycerophosphate dehydrogenase in the same fibre types can be different in different muscles. We defined the muscle fibre types (I, IIA and IIB) on transversal sections of frozen muscles according to their myofibrillar ATPase activity in alkaline and acidic media. We excised extensor digitorum longus, tibialis anterior and diaphragm muscles of five Wistar rats. In the same fibres we immunohistochemically demonstrated myosin heavy chains (MHC) I, IIA, IIB and IIX and histochemically and histophotometrically determined the activities of succinate-dehydrogenase and glycerophosphate dehydrogenase. On the basis of the measured values we differentiated fibres in oxydative, glycolytic and oxydative-glycolytic. We found out, that MHC I are present in type I fibres (in extensor digitorum longus muscle aiso in type IIA fibres), MHC IIA and IIB are present in IIA fibres and also in IIB fibres in all muscles. We defined MHC IIX in fibres which are histochemically type I, IIA and I IB. Anyhow, we found no pure IIX fibres. The greatest percentage of oxidative fibres was found in diaphragm, of glycolytic in extensor digitorum longus and of oxydative-glycolytic in the outer portion of tibialis anterior muscle. Fibres, containing MHC I, IIA or IIB belong to all three metabolic types, although the percentage of oxydative, glycolytic and oxydative-glycolytic fibres can be different in different muscles. Most fibre types present in diaphragm posess higher succinate-dehydrogenase activity than do the same fibre types in other muscles.
Deskriptorji     MUSCLE FIBERS
MYOSIN
RATS
IMMUNOHISTOCHEMISTRY