Trypanosoma cruzi: histochemical characterization of parasitized skeletal muscle fibers

C57B1/6 mice were infected with Brasil strain Trypanosoma cruzi trypomastigotes. The leg muscles of the mice were serial-sectioned with a cryostat, and individual fibers were classified histochemically as type I or type II on the basis of succinic dehydrogenase or adenosine triphosphatase activity. Although markedly more type II fibers were present in the leg muscles, the percentage of infected type I fibers was nearly five-fold higher than type II. This is the first demonstration of a preferential in vivo distribution of T. cruzi in muscle fibers based upon muscle type.     

Examination of chronically de-efferented cat muscle spindles for cholinesterase activity

Summary Cat tenuissmus muscles were deprived of motor nerve supply for three months by sectioning of the appropriate ventral spinal roots. Muscle spindles were located in the chronically de-efferented muscles and examined histochemically in serial transverse sections. Staining for nicotinamide adenine dinucleotide tetrazolium reductase showed that the spindle sensory innervation was preserved. The de-efferented intrafusal muscle fibers retained their differential staining with the reaction for myosin adenosine triphosphatase. However, all cholinesterase-active areas that are normally found along nuclear bag and nuclear chain intrafusal fibers demonstrated loss of the enzyme activity in the chronically de-efferented spindles. It is concluded that all histochemically demonstrable cholinesterase activity within the cat muscle spindle is dependent upon the continuous presence of motor innervation.     

Trypanosoma cruzi: Histochemical Characterization of Parasitized Skeletal Muscle Fibers1

C57B1/6 mice were infected with Brasil strain Trypanosoma cruzi trypomastigotes. The leg muscles of the mice were serial-sectioned with a cryostat, and individual fibers were classified histochemically as type I or type II on the basis of succinic dehydrogenase or adenosine triphosphatase activity. Although markedly more type II fibers were present in the leg muscles, the percentage of infected type I fibers was nearly five-fold higher than type II. This is the first demonstration of a preferential in vivo distribution of T. cruzi in muscle fibers based upon muscle type.     

REGENERATION OF PIGEON FAST AND SLOW MUSCLE FIBER TYPES AFTER PARTIAL EXCISION AND MINCING

The pigeon's metapatagialis muscles, containing fast fibers in two slips and slow fibers in another slip, were excised for a third of their length, minced, and replaced into their previous sites. After regeneration, the pattern of fiber types and their ATPase and oxidative enzymes were examined histochemically. Ultrastructural examination was carried out on the fast fibers. After 4–17 wk the muscles had regenerated into patterns histochemically similar to the controls only within the slip containing fast fibers. The slow slip was much less regenerated, and had a histochemically embryonic composition. Fiber types were characterized and their cross-sectional areas measured, and the degree of atrophy was greatest in the large fast fibers and the slow fibers. Ultrastructural studies revealed a number of alterations of the mitochondria, including dense and light areas in the matrix and an altered pattern of the cristae into parallel tubular or vesicular aggregations. Other changes included dilated sarcoplasmic reticulum, myofibril disorganization, and a compaction of filaments. The slow fibers were thought to be slower in their regeneration rates because of the pattern of multiple innervation's producing a more complex regenerative pattern.     

OXIDATIVE AND HYDROLYTIC ENZYMES IN THE NEPHRON OF NECTURUS MACULOSUS : Histochemical, Biochemical, and Electron Microscopical Studies

The distribution of oxidative and hydrolytic enzyme activities along the nephron of Necturus maculosus Rafinesque was studied histochemically. The proximal tubule possessed all the demonstrable enzyme activities associated with the hexose-monophosphate shunt and glycolysis, but lacked detectable succinic dehydrogenase and cytochrome oxidase activities. Krebs cycle enzymes other than succinic dehydrogenase were easily detectable. The distal tubule, on the other hand, possessed no detectable hexose-monophosphate shunt enzyme activities, but all demonstrable glycolytic and Krebs cycle enzymes and cytochrome oxidase were present in high activity. These data indicate that the proximal tubule of Necturus probably cannot depend, as can the distal tubule, on the Krebs cycle and cytochrome system to provide energy for its transport processes, an inference supported, in general, by available physiological evidence. The question of the importance of the hexose shunt to proximal tubular function arises. Evidence is presented that the proximal tubular blood supply is primarily venous in nature, a hypothesis which would correlate well with its anaerobic metabolic pattern. In addition, the absence of cytochrome oxidase and succinic dehydrogenase from the proximal tubular cells implies either that they possess very few mitochondria, or that their mitochondria have a very unusual enzymatic pattern. Electron microscopical observations and data obtained from the measurement of the enzyme activities of homogenates of Necturus kidney are presented which indicate that the second hypothesis is more probably correct.     

A histochemical study of postnatal differentiation of skeletal muscle with reference to functional overload.

Postnatal differentiation and growth of the fibers comprising the tonic soleus and phasic plantaris muscles, were investigated histochemically in kittens. Compensatory hypertrophy was induced by ablation of the synergistic gastrocnemius muscle.At birth both muscles consist of relatively homogeneous fiber populations as demonstrated by myosin ATPase and succinic dehydrogenase activities and glycogen content (PAS method). Differential myosin ATPase activities become evident during the first week (soleus and plantaris), while diversification of fiber types according to SDH and glycogen develop gradually and independently during the first 2 mo of life (plantaris).Compensatory hypertrophy is associated with a substantial enlargement of both dark and light fibers (incubated for myosin ATPase) and, with increases in SDH activity which are most notable in fibers that normally are low in this enzyme. The normal growth associated reduction in the percentage of fibers with high myosin ATPase activity is significantly accelerated in the hypertrophic soleus, while the hypertrophic plantaris, which normally undergoes only a slight reduction in the percentage of such fibers, is unaffected. These results underline the paramount role of the nerve fiber in the process of differentiation but also indicate that functional overload exerts a modifying influence on this process.     

Variation of phosphorylase distribution in skeletal muscles

Summary Glycogen phosphorylase, glycogen alpha-4 UDP-glucosyl transferase, glycogen, and some enzymes were histochemically examined in rat skeletal muscles. Phosphorylase activity was abundantly demonstrated not only in large fibers of the white muscle, but also in small red fibers of soleus muscle and those in the deep fascicles of gastrocunemius and quadriceps femoris muscles. Small fibers with high phosphorylase activity did not always revealed high LDH activity.Native glycogen was abundant mostly in small fibers or in middlesized fibers. Neither glycogen synthetase, nor glycogenolytic enzyme activity was directly proportionate to native glycogen content.On Leave from Cancer Research Institute, Faculty of Medicine, Kyushu University, Fukuoka, Japan.     

Enzyme histochemistry of the mesocoxal muscles of Periplaneta americana

Histochemical techniques have been employed to characterize enzymatic activity in the mesocoxal muscles of the cockroach, Periplaneta americana. Through our studies of the enzymes myosin-ATPase, NADH reductase, succinic dehydrogenase (SDH), and lactic dehydrogenase (LDH), we were able to classify fibers within these muscles according to criteria established for muscle fibers of vertebrates. Many of the mesocoxal muscles possess two different and distinct populations of fibers, whereas the remaining muscles are homogeneous with respect to their constituent fibers. The data presented here indicate biochemical heterogeneity for muscles of differing structural and functional features and possible neurotrophic influences upon oxidative enzymes and myosin-ATPase isozymes.     

Distribution of three types of muscle fiber in the skeletal muscles of Rana temporaria frogs (according to histochemical findings)]

On 15 skeletal muscles with different functional profile (flexors and extensors, trunk muscles and muscles of the head) and different embryonic origin (somatic and visceral), it has been shown that muscles of R. temporaria are mixed. Muscle fibers are divided into three groups which differ in the content of lipids, the activity of succinic dehydrogenase and localization of myofibrils on a cross section. On the basis of the data obtained and those in literature, these fiber groups are qualified as phasic, tonic and transitional (slow phasic) ones. Both phasic and tonic fiber groups are uniform, whereas transitional fibers form a broad specturm. Most of the muscles studied contain all the three types of fibers. In muscles of the extremities (especially in flexors), tonic fibers together with transitional ones usually form more or less compact bundles. The highest content of tonic and transitional fibers was found in muscles which do not directly participate in locomotion. If muscles contain only two types of fibers (phasic and transitional ones), these fibers form a mosaic structure.     

Fiber subtype distribution of pharyngeal dilator muscles and diaphragm in the cat

In previous studies differences were frequently found between the pharyngeal dilator muscles and the thoracic respiratory muscles in their patterns of electrical and mechanical activity during the respiratory cycle, with both resting and stimulated breathing. However, little is known about the intrinsic properties of the pharyngeal muscles and how they relate to the intrinsic properties of the diaphragm. In the present study, the fiber subtype distributions of two pharyngeal dilator muscles, the geniohyoid and the sternohyoid, were ascertained histochemically in the cat. The geniohyoid and the sternohyoid muscles had a preponderance of fast glycolytic (FG) fibers (mean 48 and 55%, respectively), a smaller number of fast oxidative-glycolytic (FOG) fibers (mean 36 and 31%, respectively), and few slow oxidative (SO) fibers (mean 16 and 14%, respectively). The percentages of SO fibers of both hyoid muscles were significantly (P less than 0.01) lower than that of the costal diaphragm, and the percentages of FOG and FG fibers were significantly higher than that of the diaphragm. In conclusion, the geniohyoid and sternohyoid muscles have histochemical characteristics usually associated with fast contraction and intermediate endurance properties.     

Morphofunctional and histochemical characteristics of the hindlimb muscles of the Rana temporaria in ontogeny

Mixed muscles of adult frogs respond to the increase in external potassium and to Ach by polyphasic contracture which is due to asynchronous activity of various groups of muscle fibers (fast phasic, intermediate and tonic ones). In the developing in vivo hindlimb muscles, the predominance of phasic contractile response and relatively weak tonic one were noted. In contrast to definitive muscles, in which maximum potassium and acetylcholine contractures are identical, growing muscles produce weak contractile reaction to Ach. Ach sensitivity of the developing muscles (as revealed by the contracture) is lower than in the definitive ones. Histochemical (studies on the lipid content and the activity of succinate dehydrogenase) and morphometric (the ratio of muscle fibers of different types at different stages of development, comparison of their diameters, relative size of tonic bundle, etc.) studies indicate that the development of morphological substrate for tonic contractions (tonic and intermediate muscle fibers) takes place at a lower rate as compared to the development of the substrate for phasic contractions. However, histochemically tonic fibers may be revealed already at the stage of myotubes.     

A histochemical and enzymatic study of the muscle fiber types in the water monitor, Varanus salvator

Histochemical analysis of five muscles from the water monitor, Varanus salvator, identified three major classes of fibers based on histochemical activities of the enzymes myosin ATPase (mATPase), succinic dehydrogenase (SDH), and alpha-glycerophosphate dehydrogenase (alpha GPDH). Fast-twitch, glycolytic (FG) fibers were the most abundant fiber type and exhibited the following reaction product intensities: mATPase, dark; SDH, light; alpha GPDH, moderate to dark. Fast-twitch, oxidative, glycolytic (FOG) fibers were characteristically mATPase, dark; SDH, light; alpha GPDH, moderate to dark. The third class of fibers had the following histochemical characteristics: mATPase, light; SDH, moderate to dark; alpha GPDH, light. These fibers were considered to be either slow twitch, or tonic, and oxidative (S/O). Pyruvate kinase (PK), alpha GPDH, and citrate synthase (CS) activities were measured in homogenates of the same muscles studied histochemically. There was a positive relationship between both PK and alpha GPDH activities and the percentage of glycolytic fiber types within a muscle. Likewise, CS activities were greater in muscles high in FOG and S/O content. Based on CS activities, Varanus S/O fibers were eight-fold more oxidative than FG fibers within the same muscle. PK/CS ratios suggested that FG fibers possess high anaerobic capacity, similar to the iguanid lizard Dipsosaurus. The fiber type composition of the gastrocnemius muscle, relative to that of other lizard species, suggests that varanid lizards may possess a greater proportion of FOG and S/O fibers than other lizards.     

Antennal muscles and fast antennal movements in ants

The antennal movements of eight ant species (subfamilies Ponerinae, Myrmicinae, and Formicinae) are examined by high-frequency videography. They show a wide range of antennal velocities which is generated by antennal muscles composed of particularly diverse muscle fibers. Fiber diameter, sarcomere length and histochemically assessed myosin ATPase activity suggest that some thin fibers are fairly slow, while the bulk of antennal muscle fibers show intermediate or fast properties. These morphological properties correlate with the antennal movement velocities measured for the respective species. Based on their morphology, the fibers that generate the fast antennal retraction in some trap-jaw ants appear particularly fast and comprise the shortest sarcomeres yet described (1.1 μm). Accepted: 2 January 1997     

Succinic dehydrogenase and cholinesterase activities in the skeletal muscles of the desert rat and the albino rat

The deltoid and gluteus maximus of the desert rat and the albino rat were examined histochemically for the distribution of succinic dehydrogenase (SDH) and cholinesterase (ChE). SDH activity showed that the deltoid and gluteus maximus muscles of the two animals consisted of three types of muscle fibres, with a predominance of muscle fibres that have higher SDH activity in both the deltoid and gluteus maximus muscles of the desert rat than in the albino rat. The mean diameter of all muscle fibres in the deltoid and gluteus maximus muscles and their ratios to the average body weight were determined in both animals. The desert rat showed a statistically significant increase in those ratios compared with the corresponding ratios for the albino rat. ChE activity showed that the deltoid and gluteus maximus muscles are richly innervated by intensely positive ChE motor end-plates with a predominance of plaque-like terminals. The mean diameters of the end-plates and the ratios of these diameters to the diameter of the muscle fibres together with their ratios to the body weight were determined. A correlation between these values and the histological findings is proposed.     

Changes in the metabolic profile of the equine gluteus medius as a function of sampling depth

1. Cross sections from the middle of the gluteus medius were removed from 10 adult horses and used to evaluate changes in histochemically determined muscle fiber type and biochemically determined metabolic enzyme activities as a function of sample depth. 2. Muscle fiber types determined using histochemical methods for myosin ATPase (pH 9.4) and succinic dehydrogenase (SDH) activity indicated percent fast-twitch glycolytic (FG) muscle fibers decreased and slow-twitch oxidative (SO) fibers increased as a function of increasing sampling depth. 3. Percent histochemically determined fast-twitch oxidative glycolytic (FOG) fibers decreased slightly only in the deepest region of the gluteus medius. 4. Citrate synthase (CS) enzymatic activity, used as a marker for mitochondrial oxidative potential, increased 2.5-fold in activity per g of muscle protein from 1 to 8 cm sampling depth. 5. 3-hydroxyacyl-CoA dehydrogenase (HAD) enzymatic activity, used as a marker for lipid oxidation potential, increased 3-fold in activity per g of muscle protein when the depth increased from 1 to 8 cm. 6. Phosphorylase (PS) enzymatic activity, used as a marker for potential glycogen utilization, decreased 50% in activity per g of muscle protein when going from 1 to 8 cm. 7. Lactate dehydrogenase (LDH) enzymatic activity, used as a marker for anaerobic glycolytic potential, decreased about 50% in activity as the sampling depth increased from 1 to 8 cm. 8. In summary, the superficial portion of the equine gluteus medius was found to be more glycolytic and less aerobic in its metabolic profile than deeper regions. The muscle became progressively more aerobic and less glycolytic with increasing sampling depth.     

Properties of standard avian slow muscle grafts following long-term regeneration

The tonic anterior latissimus dorsi (ALD) of adult pigeons was orthotopically homografted and evaluated after 11 months of regeneration for histological, histochemical, electromyographic (EMG), and mechanical properties. The resting EMG activity of the grafts was lower in amplitude than that of the controls, but showed the tonic pattern typical for these tonic muscles. The control and grafted muscles had a histochemically homogeneous population of fibers with moderate myofibrillar adenosine triphosphatase activity. Succinic dehydrogenase activity was moderate for the control muscles, but low for the grafts. The regenerated muscles had fewer and smaller fibers and had much larger intersynaptic distances. Both the regenerated and the contralateral control muscles were slow contracting and maintained tetanic tension for prolonged periods with direct electrical stimulation. The relaxation was slower in the grafted muscle than in the control. The grafts produced 40% of the maximum tension of the control muscles, but the rate of tension development was similar between the two groups. The results indicate that the tonic properties were regenerated, but the innervation pattern was altered and the grafted muscles did not have normal mature fibers even after long-term regeneration.     

去神经对快,慢肌纤维肌球蛋白ATPase影响的组织化学观察

本文用组织化学方法观察了豚鼠比目鱼肌(SOL)和腓骨第三肌(PT)在去神经后其快、慢纤维肌球蛋白ATPase特性的变化。在正常肌肉中Ⅰ型(慢)纤维和Ⅱ型(快)纤维分别具有酸和碱稳定ATPase活性。慢纤维在去神经后出现了碱稳定ATPase活性,而快纤维则无明显变化。结果表明,只有慢纤维的肌球蛋白ATPase特性才与神经支配有关。     

Muscle fiber selectivity of Trichinella spiralis and Trichinella pseudospiralis (1983)

The biceps, semimembranosus, biceps femoris, and soleus muscles of female Rockland Wistar mice infected with either 1,000 Trichinella spiralis or 1,000 Trichinella pseudospiralis larvae were removed on days 12, 14, 16, and 18 post-infection (PI), sectioned and stained histochemically for their myosin ATPase activity. Light microscopic examination of the sections revealed that larvae of T. spiralis invade only the slow twitch muscle fibers, and those of T. pseudospiralis invade both the fast twitch and the slow twitch fibers. In sections obtained from mice infected with either parasite and killed on days 16 and 18 PI, identification of the majority of the infected fibers as fast twitch or slow twitch was not possible due to pathological modification of infected fibers.     

A Histochemical Study of Normal and Denervated Red and White Muscles of the Rat

The distribution and characterization of the fibers of normal and denervated red and white muscles of the albino rat are reported in this study. Histochemical procedures for succinic dehydrogenase, lipides, adenosinetriphosphatase, esterase, and glycogen were utilized to differentiate muscle fibers, and these methods facilitated the study of the distribution of fiber types within whole muscle. Muscle fibers of the granular type (dark or red fibers) can be clearly distinguished from those with clearer sarcoplasm (light or white fibers) by methods for demonstrating succinic dehydrogenase, lipides, and esterase. The method for adenosine-triphosphatase reveals differences only under the special conditions described in the text. Additional fiber types are described in the cat's diaphragm and in the extrinsic ocular muscles of the rat. Succinic dehydrogenase and adenosinetriphosphatase activities of the soleus and biceps femoris were studied 14 days after denervation of these muscles. The histochemical findings are discussed principally in the light of current biochemical knowledge of these enzymes.