Effect of ecdysterone and juvenoid on the developmental involution of flight muscles in Acheta domestica

Morphogenesis and degeneration of the flight muscles in Acheta domestica was studied. The dorso-longitudinal flight muscles (DLMs) degenerate during the fourth day after adult ecdysis and the dorso-ventral flight muscles (DVMs) on the fifteenth day. In the presence of an intact innervation the degeneration of the DLMs can be retarded for 2 days by the injection of ecdysterone into very young adults. This retardation may also result in hypertrophy of the muscle fibres. The injection of ecdysterone, even in high doses, did not affect the flight muscle remnants. No notable changes have been found in the degeneration of DLMs by ovarectomy. Thus, the degeneration of flight muscles and the development of ovaries appear to be independent processes.The DLMs are homogeneous in fibre pattern in respect to succinic dehydrogenase, an important oxidative enzyme, and to ATPase activity, but the muscle fibres do not show any phosphorylase activity.     

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.     

A histochemical study of cervical motor neurons and the posterior latissimus dorsi muscle in normal and dystropic chickens.

A chromatolysis study, 14 to 21 days following denervation, showed the spinal cord representation of the nerve to the posterior latissimus dorsi muscle to be in the ventrolateral cell column between cervical ganglia 14 and 15. to characterize cevical neruos nt undergoing chromatolysis, histochemical stuies were done the cords of additional nondenervated animals. Staining reactions for beta-hydrocybutyrate dehydrogenase, succinic dehydrogenase and cholinesterase did not reveal any quantitative differences between motor neurons in cervical segments 14 and 15 of normal and dystrophic birds. Motor neurons are positive for beta-hydroxybutyrate dehydrogenase and succinic dehydrogenase, but the surrounding neuropil is positive for the latter only. No pseudocholinesterase activity is found in the ventral horn cells, but true cholinesterase is present in most of the neurons...     

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.     

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.     

Succinic dehydrogenase activity of the respiratory muscles of a fresh-water teleost, Bagarius bagarius (Ham.) (Sisoridae, Pisces).

Functional morphology including the origin, insertion, and innervation of the respiratory muscles in relation to buccal pressure pump and opercular suction pumps in a fresh-water bottom dwelling siluroid fish, Bagarius bagarius have been studied. Histochemical studies were made on the succinic dehydrogenase activity of adductor mandibulae, retractor tentaculi, levator operculi, dilatator operculi, adductor operculi, intermandibularis, interhyoideus, hyohyoideus superior and constrictor branchialis. The intensity of reaction reveals the presence of three types of muscle fibres in some of the respiratory muscles. The muscle containing red muscle fibres are mostly innervated by the branches of the VIIth cranial nerve. The retractor tentaculi consists of superficial white muscle fibres and the interior part is dominated by red muscle fibres. The muscles (adductor operculi, levator operculi, dilatator operculi, interhyoideus, hyohyoideus superior) concerned with the opercular suction pumps are of mixed type and consist of white and red muscle fibres, whereas adductor mandibulae and intermandibularis are made up entirely of white muscle fibres. The adductor muscle bundles of the constrictor branchialis, which are responsible for movement of gill filaments, are dominated by the red muscle fibres. The abductor part, however, is made up entirely of white muscle fibres.     

THE DISTRIBUTION OF HISTOCHEMICALLY DEMONSTRABLE SUCCINIC DEHYDROGENASE AND OF MITOCHONDRIA IN TONGUE AND SKELETAL MUSCLES

Various skeletal muscles show considerable variations in histochemically demonstrable succinic dehydrogenase activity. In muscles from the lower extremities, the back, and the abdominal wall, only some fibers reveal evidence of enzymatic staining. In the diaphragm and masseter more fibers react positively. In the tongue, however, all fibers show marked activity comparable to that found regularly in the heart. There is a close similarity in the distribution of histochemically demonstrable succinic dehydrogenase and stainable mitochondria in tissue sections.     

Cell-Cell Recognition in the Regenerating Neuromuscular System of the Cockroach

SYNOPSIS. The neuromuscular system of the cockroach containsmotor neurons and muscles that can be identified in all individualinsects When the axons of these motor neurons are damaged theyregenerate and eventually reform synapses only with the originaltarget muscles However at early times after axotomy transientinappropriate functional connections are made between regeneratingneurons and muscles that theynever normally innervate Laterthe inappropriate synapses are inactivated, the inappropriateaxon branches eliminated and the original innervation patternreformed A cellcell recognition between identified motor neuronsand muscles is required to explain these observations, particularlyin light of experiments demonstrating the absence of competitionbetween appropriate and inappropriate axon terminals withinthe muscle. A minimum biochemical requirement of such a cell-cell recognitionis the existence of molecules whose presence in muscles correlateswith the innervation by identified motor neurons Using fluoresceinlabelled plant lectins to detect muscle surface glycoproteinssuch molecules have been identified In addition, there shouldbe molecular differences among the surfaces of the axon terminalsof the various identified motor neurons Hybrid oma techniqueshave enabled us to obtain monoclonal antibodies that bind tosurfaces of axon terminals of some motor neurons and not othersThese lectin receptors and antigens are good candidate recognitionmacromolecules Other molecules essential for axonal regenerationhave been identified by their presence in embryonic and adultregenerating neurons and their absence from intact adult neurons.     

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.     

Protein composition of cockroach muscles: Identification of candidate recognition macromolecules

The protein composition of each of the coxal depressor muscles from the leg of the cockroach, Periplaneta americana, was analyzed by SDS polyacrylamide gel electrophoresis. The proteins from each muscle were fractionated according to their extractability in Ringer's solution, 1% Triton X-100 and 1% SDS. The gel protein patterns of the fractionated muscles revealed some biochemical differences that could be correlated with mechanical and ultrastructural differences observed among the muscles. In addition, proteins were detected that were considered to be candidate recognition macromolecules that are responsible for the intercellular recognition process that enables regenerating motor neurons to specifically recognize and make stable, functional connections only with the muscles to which they were originally connected. The major evidence for this identification of candidate recognition macromolecules was that their presence in the muscle could best be correlated with innervation by an identified motor neuron. In addition, these proteins remain present in denervated muscles for at least as long as it takes for the original innervation pattern to be reformed by the regenerating motor neurons.     

Musculature and innervation of the neck of the desert locust,Schistocerca gregaria (Forskål)

The innervation of each of the muscles involved in mediating head movement in the desert locust Schistocerca gregaria is described in detail. The number of motor neurones to each muscle and the neutral pathway and ganglion of origin of each are deduced from both histological and electrophysiological evidence. Only two of the muscles are, on histological evidence, innervated by as few as four different neurones, while several receive more than ten, and one at least 13. Individual muscles are shown physiologically to receive, in a few cases, as many as six different motor neurones. At least six muscles are innervated by motor neurones originating in more than one ganglion. One group of four muscles consisting in total of less than 100 muscle fibres receives more than 20 different motor neurones from three different ganglia through three or four different nerve roots. In these muscles, many single muscle fibres receive innervation from at least two different ganglia. It is concluded that the segmental nature of an insect muscle can not be deduced solely from a knowledge of the ganglion of origin of the motor innervation to that muscle. The innervation patterns that exist today must reflect past evolutionary development, but changes in the peripheral distribution of motor neurones, or migration of motor neurone cell bodies from one ganglion to another, or the development of additional motor neurones, or several of these factors together, must have formed a part of that development.     

Neuroanatomy of the sucking pump of the moth, Manduca sexta (Sphingidae, Lepidoptera)

Knowledge of the neuroanatomy of the sucking pump of Manduca sexta (Sphingidae) is valuable for studies of olfactory learning, pattern generators, and postembryonic modification of motor circuitry. The pump comprises a cibarial valve, a buccal pump, and an esophageal sphincter valve. Cibarial opener and closer muscles control the cibarial valve. Six pairs of dilator muscles and a compressor muscle operate the buccal pump. The cibarial opener and one pair of buccal dilator muscles are innervated by paired neurons in the tritocerebrum, and the cibarial opener has double, bilateral innervation. Their tritocerebral innervation indicates that these muscles evolved from labro-clypeal muscles. The remaining paired buccal dilator muscles each are innervated by an unpaired motor neuron in the frontal ganglion. These motor neurons project bilaterally through the frontal connectives to dendritic arborizations in the tritocerebrum. These projections also have a series of dendritic-like arborizations in the connectives. The cibarial closer and buccal compressor muscles are also innervated by motor neurons in the frontal ganglion, but only the closer muscle neuron projects bilaterally to the tritocerebrum. The innervation of the pump muscles indicates that they are associated with the stomodaeum, and, therefore, the buccal pump evolved from the anterior stomodaeum rather than from the cibarium.     

Comparative microspectrophotometric study of the activity of oxidative enzymes in separate types of fibers of the skeletal muscle of rats in the normal state and in experimental ischemia]

Microspectrophotometrical investigation of the activity of oxidative enzymes (glutamatdehydrogenase, cytoplasmic and mitochondrial alpha-glycerol phosphate dehydrogenase, succinic acid dehydrogenase and glucose-6-phosphatedehydrogenase) in certain types of muscular fibres of m. soleus, gastronemius and quadriceps of rats during experimental stenosins of the abdominal part of the aorta has shown the existence of certain cyclic changes in the enzymic activity of different periods after graded constriction which may be associated with arising of adaptational reactions of metabolic systems in striated muscles in response to chronic hypoxia.     

The effects of pre- and perinatal undernutrition on the succinic dehydrogenase content of muscle fibres from fast and slow rat muscles

Summary Male rats were subjected to early undernutrition by limiting the mothers' food supply by 50% during pregnancy and lactation. At age 36 weeks, quantitative cytochemical determinations of succinic dehydrogenase activity were made in muscle fibres from the anterior tibialis and soleus muscles. Marked decreases were found in the former muscle but relatively little decrease was seen in the latter. This response of the muscles to early undernutrition was discussed with reference to other studies on pre and post-natal starvation.     

Histochemical demonstration of enzymatic heterogeneity within the mesocoxal and metacoxal muscles of Periplaneta americana

Enzymatic activity in the mesocoxal and metacoxal muscles of the cockroach, Periplaneta americana, has been characterized using histochemical techniques. Our interpretation of the histochemical stains for myosin-ATPase (pre-incubated at pH 9.4, 10.4 and 4.3). NADH reductase, succinic dehydrogenase (SDH), and lactic dehydrogenase (LDH) has enabled us to classify fibres within these muscles according to established fibre typing strategies. The results reaffirm the biochemical heterogeneity reported for the mesocoxal muscles and allow us to confirm the expected heterogenity in the homologous metacoxal muscles. These techniques have proven to be an effective tool for assessing the biochemical properties of muscle fibres.     

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.     

Plasticity in mammalian skeletal muscle.

While it has been recognized for many years that different limb muscles belonging to the same mammal may have markedly differing contractile characteristics, it is only comparatively recently that it has been demonstrated that these differences depend upon the motor innervation. By appropriately changing the peripheral nerve innervating a mammalian skeletal muscle, it is possible to change dramatically the contractile behaviour of the reinnervated muscle. The manner by which the motor innervation determines the nature of a muscle fibre's contractile machinery is not completely understood, but it appears that the number and pattern of motor nerve impulses reaching the muscle play an important role. The biochemical changes occurring within muscle fibres whose contractile properties have been modified by altered motor innervation include the synthesis of different contractile proteins.     

Metabolic differentiation of homologous leg muscles of two aquatic birds at the level of enzymatic organization

The quantitative determination of succinic dehydrogenase (SDH), hexokinase (HK), phosphorylase, phosphofructokinase (PFK), glycerol-3-phosphate dehydrogenase (G-3-PDH) and lactate dehydrogenase (LDH) was carried out in the homologous leg muscles of two aquatic Birds. It appears that the leg muscle fibres of the coot, a surface swimmer are more oxidative in nature and appear to utilize glucose as source of energy. The leg muscles of the dabchick, a diving Bird, on the other hand, seem to depend on glycogen as source of energy. The relative activity levels of HK, phosphorylase and PFK support the accepted r?le of glycogen as primary substrate of carbohydrate catabolism in the leg muscles. The ratio of G-3-PDH/LDH in the leg muscles revealed that glycerol 3-phosphate cycle appears to be insufficient to account for the major part of NADH oxidation. However, the LDH activity is quite high in all the muscles. These results led us to believe that glycerol 3-phosphate cycle may function during rest, when the rate of glycolysis will be low.     

Plagiorchis elegans: Histochemical localization of dehydrogenases in the cercarial stage

Cercariae of Plagiorchis elegans Rudolphi 1802 collected from experimentally infected snails, Lymnaea palustris, were subjected to various histochemical tests for dehydrogenase systems. A high degree of activity was demonstrated for succinic dehydrogenase (EC 1.3.99.1), malic dehydrogenase (EC 1.1.1.37), isocitric dehydrogenase (EC 1.1.1.41), α-glycerophosphate dehydrogenase (EC 1.1.1.8), and glucose 6-phosphate dehydrogenase (EC 1.1.1.49). These enzymes were present in the tegument, tail, caudal pocket, excretory bladder, acetabulum, and oral sucker, particularly in the muscles around the stylet. Only moderate activity was obtained for lactic dehydrogenase (EC 1.1.1.27) and 6-phosphogluconate dehydrogenase (EC 1.1.1.44) at these sites, glutamic dehydrogenase (EC 1.4.1.2) was localized only in the tails of the cercariae and tests for alcohol dehydrogenase (EC 1.1.1.1) were completely negative. The cerebral ganglia and its commissures stained intensely in the tests for succinic, isocitric, α-glycerophosphate, and glucose 6-phosphate dehydrogenase systems. The results indicate the possibility that several energy-producing sequences may be available to these cercariae.     

Neural control of embryonic acetylcholine receptor and skeletal muscle

The manner by which motor neurons exert control over the distribution and number of acetylcholine receptors, and muscle development was investigated in the superior oblique muscle of white Peking duck embryos. Clusters of receptors in the normally developing muscle first appeared on day 10 of incubation as determined with I125 alpha-bungarotoxin autoradiography. The initial appearance of receptor clusters coincided with the arrival of motor nerve fibers in the muscle. Clusters of receptors also appeared in normal fashion in muscles made aneural by destruction of motor neurons on day 7. But after day 14 these clusters had disappeared and no new clusters were seen thereafter in the aneural muscle. Receptor clusters persisted throughout development in muscle in which neuromuscular transmission was blocked with either curare or botulinum toxin and in muscles denervated on day 10.5, i.e., shortly after the initial nerve-muscle contact but prior to the onset of muscle activity. A progressive increase in the total number of receptors and in the total amount of protein occurred during the course of normal development. However, the specific activity of the receptor protein declined sharply following innervation on day 10. The total number of receptors and the specific activity of the receptor was affected depending on whether the motor neurons were destroyed before or after innervation and following chronic blockade of neuromuscular transmission. The half-life of the receptor protein was similar in normal, aneural, and paralyzed muscles (26, 25, 26 h, respectively). Measurements of total protein indicated that essentially no muscle growth occurred in the complete absence of innervation. Paralyzed muscles continued to develop but at a slower pace.