Histochem J. 2001 Apr; 33(4): 213-9.

Nitric oxide synthase isoforms I, III and protein kinase-Ctheta in skeletal muscle fibres of normal and streptozotocin-induced diabetic rats with and without Ginkgo biloba extract treatment.

Punkt K, Zaitsev S, Park JK, Wellner M, Buchwalow IB.

Institute of Anatomy, University of Leipzig, Germany.

The expression of nitric oxide synthase (NOS) isoforms I, III and protein kinase-Ctheta (PKCtheta) in rat vastus lateralis muscle was demonstrated immunohistochemically and then correlated to the physiological metabolic fibre types: SO (slow-oxidative), FOGI, FOGII (fast-oxidative glycolytic; I more glycolytic, II more oxidative), and FG (fast-glycolytic). NOS expression in muscles from different experimental groups (normal and diabetic rats, with and without Ginkgo biloba extract treatment) was assayed by Western blotting. Generally, NOS I and PKCtheta were co-expressed in fibres with predominantly oxidative metabolism (SO, FOGII). This suggests an interplay of PKCtheta and NOS I in nitric oxide production by oxidative fibres. NOS III was more highly expressed in fibres with predominantly glycolytic metabolism (FOGI, FG). A somewhat lower NOS I immunoreactivity was also found in NOS III positive fibres suggesting that NOS III and NOS I are co-expressed in these fibres. Western blotting revealed that NOS I as well as NOS III expression in the vastus lateralis muscle was down-regulated in diabetes and increased after Ginkgo biloba extract treatment. These effects may be associated with a diminished glucose uptake by myocytes of diabetic musclesand with an improved muscle function after Ginkgo biloba treatment.