Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.8.1.4 (diaphorase)
 2,754 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A reexamination of the question of specificity of reinnervation of fast and slow muscle was undertaken using the original "self" nerve supply to the fast lateral gastrocnemius (LG) and slow soleus muscles in the rat hindlimb. This paradigm takes advantage of the unusual situation of a common nerve branch, which supplies both a fast and slow muscle, and of the opportunity to keep the reinnervating nerve in its normal position. In addition it provides a test of the effects of cross-reinnervation among muscles of the same functional group. The properties of soleus and LG muscles and of individual muscle units were characterized in normal rats and in rats 4-14 mo after cutting the lateral gastrocnemius-soleus (LGS) nerve and suture of the proximal stump to the dorsal surface of the LG muscle. Individual muscle units were functionally isolated by stimulation of single motor axons to LG or soleus muscle contained in teased filaments in the L4 and L5 ventral roots. Motor units were classified as fast contracting fatiguable (FF), fast contracting fatigue resistant (FR), and slow (S) on the basis of criteria described in the cat by Burke et al. and applied to rat muscle units by Gillespie et al. Muscle fibers were classified as fast glycolytic (FG), fast oxidative glycolytic (FOG), and slow oxidative (SO) on the basis of histochemical staining for myosin ATPase, nicotinamide-adenine dinucleotide diaphorase (NADH-D), and alpha-glycerophosphate (alpha-GPD). Reinnervated muscles developed less force and weighed less in accordance with having fewer than normal motor units and having lost denervated muscle fibers. Normal LG contained a small proportion of S-type motor units (9%), whereas the majority (80%) of control soleus units were S type. After reinnervation, each muscle contained similar proportions of fast and slow motor units with S-type units constituting 30% of units in both muscles. When compared with the normal motor-unit sample, there was no significant change in average twitch and tetanic force in reinnervated muscles for each type of motor unit. However, the range within each type was greater, and there was considerable overlap between types. Twitch contraction time was inversely correlated with force in normal and reinnervated muscles as shown previously in self- and cross-reinnervated LGS in the cat. Changes in proportions of motor units in reinnervated LG were accompanied by corresponding changes in histochemical muscle types. This contrasted with reinnervated soleus in which the proportion of muscle fiber types was not significantly changed from normal despite significant change in motor-unit proportions.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Motor units and histochemistry in rat lateral gastrocnemius and soleus muscles: evidence for dissociation of physiological and histochemical properties after reinnervation. 295 72

The purpose of this study was to evaluate the effect of endurance exercise on the histochemistry and wet weight of the reinnervating rat plantaris muscle. Two groups of young female Wistar rats (6 weeks old), 1 sedentary denervated control (n = 13) and 1 exercised denervated experimental (n = 17), were denervated unilaterally by cutting and resecting the sciatic nerve. To effect reinnervation a skin grafting operation was carried out on the nerve so that the gap caused by resection was bridged. The third group was the sedentary non-denervated normal control (n = 10). A progressive training program of 18 weeks of treadmill running was carried out by the experimental group. Approximately 5 months after denervation, the plantaris muscles were studied histochemically for reduced nicotinamide adenine dinucleotide diaphorase (NADH-D) and mitochondrial alpha-glycerophosphate dehydrogenase (alpha-GPD) activities. Fibres were classified as "red", "white", or "intermediate" with NADH-D. Alpha-GPD differentiates "intermediate" from "red" fibre types in case of difficulty in differentiating these fibre types from each other with NADH-D. The weight of the reinnervated plantaris muscle increased significantly after exercise. The exercise did not change the fibre type proportions--including "red" fibre type--in the deep region of the reinnervating plantaris. There were significant differences between normal control and denervated control or experimental groups in histochemical fibre populations in the deep region of the plantaris. The findings of this study suggest that: treadmill running did not increase the oxidative capacity of the deep region of the reinnervating rat plantaris muscle; treadmill training did not damage the reinnervating plantaris.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Effect of endurance exercise on fibre type composition and muscle weight of reinnervating rat plantaris muscle. 358 51

1. This report describes selected histochemical and physiological properties of the motor units of adult cat soleus muscle approximately one year after self- and cross-reinnervation with the nerve of the heterogenous flexor hallucis longus (f.h.l.). Self-reinnervated f.h.l. motor units are also considered. Whole muscles were tested for fibre reaction to alkaline pre-incubated ATPase, alpha-glycerophosphate dehydrogenase (alpha-GPD) and reduced nicotinamide adenine dinucleotide diaphorase (NADH-D). Motor units were isolated and studied by splitting the ventral root in acute preparations.2. The histochemical fibre type profile in the self-reinnervated muscle was comparable to normal muscle as was mean twitch contraction time, twitch-tetanus ratio and fatigue index. The mean tetanic tension of the soleus self- and cross-reinnervated motor units appeared close to a normal soleus whereas the mean tetanic tension of the f.h.l. self-reinnervated units was significantly less than a normal f.h.l.3. An average of 14% of the fibres of the soleus cross-reinnervated muscles had high ATPase and a alpha-GPD staining intensity in contrast to normal and self-reinnervated soleus in which such fibres are absent. Thus alkaline lability of myofibrillar ATPase increased in some fibres of what was originally a homogeneous population. The small increase in the number of densely staining fibres for ATPase at an alkaline pH (14%) was associated with a 73% decrease in (mean) contraction time (41 +/- 11 ms) of the thirty-three cross-reinnervated muscle units studied, with no unit's contraction time greater than 60 ms. Mean contraction times for the self-reinnervated soleus and f.h.l. muscles were 78 +/- 31 ms and 27 +/- 8 ms respectively.4. All fibres of the soleus cross-reinnervated muscles showed intense reaction to NADH-D, as was true of self-reinnervated soleus. This staining pattern is typical of normal soleus. In concordance, these motor units consistently demonstrated a high resistance to fatigue when stimulated for a four-minute period.5. These results suggest that in the adult self-and cross-reinnervated soleus muscle, there is some active mechanism which regulates the eventual size of motor units as reflected by tetanic tension.6. Change in contraction time from that typical for a soleus unit to that similar to an f.h.l. unit remains incomplete one year after cross-reinnervation. Within this time this partial change in single motor units reflects incomplete neural control of this property rather than a mixture of self- and foreign-innervation.7. A greater degree of independence from neural control to conversion of the histochemically demonstrated myofibrillar ATPase activity exists than is the case for contraction time.
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PMID:Histochemical and physiological properties of cat motor units after self-and cross-reinnervation. 715 31

The dorsal root ganglion (DRG) neurons were classified in the rat on the basis of their metabolic enzyme properties as determined by quantitative analysis in histochemical staining. In particular, nicotinamide adenine dinucleotide-diaphorase (NADH-d) and alpha-glycerophosphate dehydrogenase (alpha-GPD) activities were examined on two serial sections from the same neurons in the lumbar (L4) DRG. The DRG neurons were classified into three groups based on the soma diameter distribution; small, intermediate and large size DRG neurons. The NADH-d activity showed a unimodal distribution in all size groups, while the alpha-GPD activity clearly showed a bimodal distribution in the intermediate and large size neurons, but not in the small size neurons.
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PMID:Metabolic properties of the sensory neurons in the rat dorsal root ganglion. 917 28