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F Mascarello

Publications and source records attributed to F Mascarello.

At least 37 records · Page 2Linked to original sources
PubMed1992

Tertiary myotubes in postnatal growing pig muscle detected by their myosin isoform composition.

The postnatal development of skeletal muscles was studied in growing pigs from 8 to 210 d of age. Indirect immunoperoxidase staining of frozen sections of porcine semimembranosus muscle and longissimus muscle revealed a distinct population of small fibers (tertiary myotubes) that were stained specifically by an antibody (anti-NE) selective for the developmental (embryonic and neonatal) isoforms of muscle myosin. At 8 d of age the other larger fibers were already anti-NE negative and differentiated into Types I and II. A gradual decrease in the number of anti-NE positive fibers together with a gradual increase in area of the remaining positive fibers was observed throughout the pigs' growth. These results may indicate that hyperplastic growth does not cease at birth. Possible mechanisms to explain the origin of these tertiary myotubes containing developmental isoforms of myosin are suggested.

Adenosine Triphosphatases↗
PubMed1991

Neonatal myosin in bovine and pig tensor tympani muscle fibres.

In previous studies of middle ear muscles, the classification of fibre types by histochemical methods was particularly difficult in the bovine and porcine tensor tympani muscle, suggesting the presence of immature fibres. We therefore reexamined the tensor tympani from pigs and cattle of various ages immunohistochemically, using a panel of antimyosin antibodies, including one (anti-NE) specific for neonatal and embryonic myosins. Fibres positive to anti-NE were found in tensor tympani in both species in all ages examined; only a few of these fibres reacted exclusively with this antibody; some also contained slow myosin and the majority also contained adult fast (type IIA) myosin. Furthermore, although the remaining fibres included some of the classical types I and IIA, the majority of them showed a mismatch between their histochemical and immunohistochemical profiles. The morphological appearance of the muscle, the widespread presence of neonatal myosin (often together with another myosin in the same fibre) and the persistence of this composition from birth to adulthood, could be explained by an incomplete development of the muscle fibres, resulting in a 'muscle' much better suited to the role of a ligament.

Aging↗
PubMed1990

Hyperplastic and hypertrophic growth of lateral muscle in Dicentrarchus labrax (L.). An ultrastructural and morphometric study.

In this EM study of lateral muscle in Dicentrarchus labrax, we observed that during the larval period, growth of the presumptive red and white muscle layers occurs both by hypertrophy (as fibres already present at hatching complete their maturation) and by production of new fibres in germinal zones specific to the two muscle layers. In the first half of larval life the presumptive white muscle increases in thickness by the addition, superficially, of new fibres derived from a germinal zone of presumptive myoblasts lying beneath the red muscle layer. In the second half of larval life new fibres produced in this same zone form the intermediate (or pink) muscle layer. Dorsoventrally the myotome grows throughout larval life, largely by addition of new fibres from germinal zones at the hypo- and epi-axial extremities. Towards the end of larval life all these germinal zones are becoming exhausted, but another source of fibres arises as satellite cells, associated with large-diameter presumptive white muscle fibres, are activated to produce new fibres. The addition of small, new fibres gives the white muscle its mosaic appearance. Morphometric analysis of fibre diameters in the white muscle confirms that whereas these hyperplastic processes are important during the larval and juvenile periods, when growth is very rapid, they have ceased by the time the adult stage is attained. By contrast, fibre hypertrophy continues through into adult life. The presumptive red muscle consists initially of a monolayer of fibres present only near the lateral line, and during larval life it grows hypo- and epi-axially by addition of fibres derived from myoblasts already present in these areas at hatching. Lying superficially to the presumptive red muscle monolayer there is a near-continuous layer of external cells with a "flattened" profile. During the second half of larval life, differentiation of these external cells into myoblasts provides the source of new fibres which are added to the red muscle layer. This process, which occurs initially in the region around the lateral line and later spreads outwards, is responsible for the increase in thickness of the red muscle.

Animals↗
PubMed1989

The adductor mandibulae muscle in teleost fish with protrusible or non protrusible jaws: a histochemical and immunohistochemical study.

A study was made of the morphology and fibre type composition of the adductor mandibulae (AM) muscle in Teleosts with very protrusible (carp), moderately protrusible (cod) and non-protrusible (trout and cat-fish) jaws. In contrast to the trout and cat-fish, in which the AM is formed by only 2 components (mandibular and mental), in the carp and cod there is a third portion (maxillary) which is more or less developed in relation to the extent of jaw protrusion. Fibre types were identified by means of histochemical staining for succinate dehydrogenase and myosin ATPase activities, and by immunohistochemistry with anti-sera specific for fish fast and slow myosins. In all the species AM is composed principally of white (fast) fibres, with a smaller proportion of red (slow) fibres. The red fibres, which appear in the deep layers only of the muscle are not found in all of the components, and in the different species are not always present in the same parts. In those parts of the AM which are mixed, a transition zone lies between the red and white areas, and is usually composed of a third, or intermediate, type of fibre with histochemical and immunohistochemical properties similar to those of the pink zone of lateral muscle. The anatomical characteristics and different fibre type compositions of the various components forming the AM are discussed in relation to the extent of jaw protrusion and the relevant physiological data concerning other movements in which this muscle participants.

Animals↗
PubMed1988

Developmental transitions of myosin isoforms and organisation of the lateral muscle in the teleost Dicentrarchus labrax (L.).

In Dicentrarchus labrax (the sea bass) the differentiation of lateral muscle fibres occurs at different stages and in different ways in the superficial (red), intermediate (pink) and deep (white) regions of the myotome. At hatching the myotomes are composed of presumptive white and red fibres, the latter forming a superficial monolayer present only near the transverse septum. At this stage, differences between the fibre types are mainly ultrastructural. From their different reactions with isoform-specific antibodies to mullet myosin, and the appearance of histochemical mATPase activity, it appears that in both red and white muscle fibres there is a transition in myosin composition from an early larval form (L1R and L1W respectively) to a late larval form (L2R and L2W) and then to the isoforms typical of adult red and white muscle. The transition from L1W to L2W in the deep muscle occurs very rapidly and early in larval life (between 10 and 28 days), whereas the equivalent transition in the superficial muscle (from L1R to L2R) is a gradual process beginning in fibres near the transverse septum and spreading hypo- and epi-axially as this layer grows around the deep muscle. The definitive adult forms (AR and AW), distinguishable by the appearance of characteristic histochemical myosin ATPase activity, are present in the superficial red muscle by 80 days, but later in the deep white muscle (by 20 months), respectively. Compared to the superficial red and deep white muscle, the intermediate (pink) muscle layer first appears relatively late (80 days), but then acquires the histo- and immunohistochemical profile characteristic of the adult form much more rapidly.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗
PubMed1988

Muscle-spindle distribution in relation to the fibre-type composition of masseter in mammals.

The various parts of the masseter muscle complex (pars superficialis, pars profunda, zygomaticomandibularis, maxillomandibularis) in the rat, guinea-pig, rabbit, cat and macaque monkey were examined to discover whether they showed any relationship between the distribution of muscle spindles and extrafusal fibre types. Intrafusal (spindle) and extrafusal fibre types in masseter were compared with those in limb muscles and were identified by a combination of standard histochemical methods and indirect immunoperoxidase staining with antibodies specific for the various isoforms of myosin characteristic of fibre types in mammalian muscle. In general, the fibre-type properties of intrafusal fibres in masseter resembled those in limb muscle spindles, but the extrafusal fibre-type composition was unlike that in most limb muscles. In the rat masseter, most of the spindles were clustered together in a few very restricted areas. Extensive fusion of the external capsules of adjacent spindles, resulting in the formation of giant spindles, was seen in the cat and monkey masseter; this was sometimes accompanied by the enclosure of extrafusal fibres within the fused spindles. Common to all species, but strongest of all in the rat, was a close association between the distributions of muscle spindles and extrafusal Type I (slow twitch) fibres within the masseter complex. Muscle spindles and Type I fibres were either absent or rarest in the superficial part of masseter, but were most common in the deep layer (pars profunda) or zygomaticomandibularis. The functional significance of these observations is discussed.

Animals↗
PubMed1987

Fibre types in extraocular muscles: a new myosin isoform in the fast fibres.

We report on the existence of a myosin heavy chain (MHC) isoform with unique structural properties in extraocular (EO) muscles. Differences in MHC composition are apparent using a polyclonal antibody prepared against myosin isolated from bovine EO muscle myosin. In enzyme immunoassays and western blotting experiments, this anti-EO myosin antibody reacted specifically with the heavy chains of EO muscle myosin and not with the heavy chains of other myosins. The distribution of this new MHC isoform in the globe rotating muscles from different mammalian species was analysed using a panel of specific anti-myosin antibodies and comparing the histochemical myosin ATPase profile of muscle fibres with their isomyosin content. Most fibres which display a type 2 ATPase reaction pattern were selectively labelled by anti-EO antibodies. A few type 2 fibres were found to react with both anti-EO and anti-2A myosin antibodies and others, located almost exclusively in the orbital layers, reacted with anti-foetals as well as anti-EO antibodies. The presence of a distinct form of myosin in EO muscle fibres is probably related to the particular functional characteristics of these muscles, which are known to be exceptionally fast-contracting but display a very low tension output.

Animals↗
PubMed1986

Histochemical and immunohistochemical profile of pink muscle fibres in some teleosts.

The pink muscle of several Teleosts was examined immunohistochemically using antisera specific for the myosins of red and white muscle, and histochemically using various methods for demonstrating myosin ATPase (mATPase) activity. In the catfish the pink muscle consists of 2 different layers of fibres. The superficial layer has a low mATPase activity after both acid and alkali pre-incubation, whereas the deeper layer has a high mATPase activity after acid and alkali pre-incubation, being more resistent to these conditions even than is the white muscle. In the trout the pink muscle is composed of fibres with the same mATPase activity as in the superficial pink muscle of the catfish, whereas in the rock goby, goldfish, mullet and guppy the pink muscle is like the deep pink layer of the catfish. Immunohistochemically the fibres of the pink muscle behave like the white muscle fibres except in the guppy and rock goby in which at the level of the lateral line there occurs a transition zone between red and pink fibres. The fibres of this region react with both anti-fast and (to a lesser extent) anti-slow myosin antisera, and have a mATPase activity which, going from the superficial to the deeper fibres, gradually loses the red muscle characteristics to acquire those of the main pink muscle layer.

Adenosine Triphosphatases↗
PubMed1985

Comparative study of myosins present in the lateral muscle of some fish: species variations in myosin isoforms and their distribution in red, pink and white muscle.

Myosin isoforms and their distribution in the various fibre types of the lateral muscle of eight teleost fish (representing a wide range of taxonomic groups and lifestyles) were investigated electrophoretically, histochemically and immunohistochemically. Polyclonal antisera were raised against slow (red muscle) and fast (white muscle) myosins of the mullet, and used to stain sections of lateral muscle. Antisera specific for fast and slow myosin heavy chains only (anti-FHC and anti-SHC respectively) and for whole fast and slow myosins (anti-F and anti-S respectively) were obtained, and their specificity was confirmed by immunoblotting against electrophoretically separated myofibrillar proteins. The ATPase activity of myosin isoforms was examined histochemically using methods to demonstrate their acid- and alkali-lability and their Ca-Mg dependent actomyosin ATPase. As expected, the predominant myosin (and fibre) type in the red muscle showed an alkali-labile ATPase activity, reacted with the anti-S and anti-SHC sera (but not anti-F or anti-FHC) and contained two 'slow' light chains, whereas the predominant myosin (and fibre) type in the white muscle showed an alkali-stable ATPase activity, reacted with anti-F and anti-FHC sera (but not anti-S or anti-SHC) and contained three 'fast' light chains. However, superimposed upon this basic pattern were a number of variations, many of them species-related. On analysis by two-dimensional gel electrophoresis fish myosin light chains LC1s, LC2s and LC2f migrated like the corresponding light chains of mammalian myosins, but fish LC1f consistently had a more acidic pI value than mammalian LC1f. Fish LC3f varied markedly in Mr in a species-related manner: in some fish (e.g. eel and mullet) the Mr value of LC3f was less than that for the other two light chains (as in mammalian myosin), whereas in others it was similar to that of LC2f (e.g. cat-fish) or even greater (e.g. goldfish). Species differences were also seen in the relative intensity of LC1f and LC3f spots given by the fish fast myosins. In most of the fish examined the red muscle layer showed some micro-heterogeneity, containing (in addition to the typical slow fibres) small numbers of fibres with a histo- and immunohistochemical profile typical of white muscle (fast) fibres. However, other immunohistochemically distinct minority fibres were found in the red muscle of the goldfish. Three types of pink muscle were distinguished: a mosaic of immunohistochemically typical red and white fibres (e.g. grey mullet).(ABSTRACT TRUNCATED AT 400 WORDS)

Anguilla↗
PubMed1984

The fibre type composition of the striated muscle of the oesophagus in ruminants and carnivores.

The fibre type composition of the striated muscle layer of the oesophagus of the cow, sheep, donkey, dog and cat was examined with standard histochemical methods and immunohistochemical staining using type-specific antimyosin sera. The heavy chain and light chain composition of oesophageal myosin was also examined using electrophoretic peptide mapping and 2-dimensional gel electrophoresis respectively. In the ruminants and donkey the oesophagus was composed of fibre types I, IIA and IIC with immunohistochemical characteristics identical to those of the same fibre types found in control skeletal muscle. In the ruminants there was a gradient in the proportion of type I fibres from 1% (at the cervical end) to about 30% (at the caudal end). In the carnivores the oesophageal muscle was composed of a very small percentage of type I and IIC fibres, but the predominant type was very different histochemically and immunohistochemically from all the fibre types (I, IIA, IIB, IIC) present in the control muscles. This oesophageal fibre type ( IIoes ) had an acid- and alkaline-stable m-ATPase activity, a moderate histochemical Ca-Mg actomyosin ATPase activity, and reacted weakly with anti-IIA and anti-IIB myosin sera. Although the light chains of the IIoes myosin were the same as the light chains of a mixture of IIA and IIB myosins, their respective heavy chains gave different peptide maps. Greater differences were obtained between the heavy chains of IIoes and other striated muscle myosins. These observations lead us to conclude that this predominant fibre type of the carnivore oesophageal striated muscle is of the 'fast' type, and contains a distinct isoform of myosin similar but not identical to the other fast type myosins.

Adenosine Triphosphatases↗
PubMed1983

The fibre-type composition of the first branchial arch muscles in Carnivora and Primates.

A combination of standard histochemical techniques and immunohistochemical staining using myosin type-specific antisera was used to determine the fibre-type composition of the muscles of first branchial arch origin (that is, masseter, temporalis, pterygoideus medialis and lateralis, tensor veli palatini, tensor tympani, anterior digastricus and mylohyoideus) in a wide range of the Carnivora and the Primates. The rare IIM fibre type was found in the first branchial arch muscles of most of the species examined, but never in the limb muscles used as controls for this study. The jaw-closer muscles (masseter, temporalis and pterygoideus medialis) were found to contain IIM fibres in all the Carnivora except the lesser panda and in all the Primates except man. When present, the IIM fibres were usually the predominant fibre type, and the only other fibre types present were types I, II or IIC. The presence of IIM fibres in the jaw-closer muscles of most of the Carnivora and the Primates seems to be associated with an aggressive bite which is required for predation by the former and defence by the latter. In both groups of species there was the member which does not have an aggressive bite, the lesser panda and man, respectively, and these (like all other orders of mammals such as Lagomorpha, Rodentia, etc.) were found to have no IIM fibres in the jaw-closer muscles. The two muscles of the first branchial arch group which are derived from the ventral constrictor muscles of the (phylogenetically) original mandibular arch never contained IIM fibres, and were composed of type I and II fibres similar to those found in the control muscles of the limb. Tensor veli palatini and tensor tympani showed species-dependent variations in fibre-type composition and did not always reflect the composition of the jaw-closer muscles. Thus their common origin with the jaw-closers cannot be responsible for the occurrence of IIM fibres in tensor veli palatini and tensor tympani in some species. Furthermore, in tensor tympani but not in tensor veli palatini, the presence of IIM fibres was always accompanied by immunohistochemically slow-tonic fibres. Finally, the regard to the association of oxidative activity with the fibre type as defined by the myofibrillar ATPase method and by the isoform of myosin present, we suggest that in the first branchial arch muscles this is probably not directly comparable to the situation in the typical limb muscle.

Animals↗
PubMed1983

An immunohistochemical study of the middle ear muscles of some carnivores and primates, with special reference to the IIM and slow-tonic fibre types.

The middle ear muscles of several species of carnivores (cat, dog, fox, ferret and stone-marten) and some New World monkeys (Callithrix, Saimiri) and Old World monkeys (Cercopithecus, Macaca) were examined. The fibre type compositions of these muscles were determined by a combination of the standard histochemical myofibrillar ATPase method, and immunohistochemical techniques using myosintype-specific antisera. Immunohistochemically slow-tonic fibres were found in the stapedius muscles of only two carnivores, the ferret and stone-marten. In all the carnivores and the New World monkeys, tensor tympani muscle contained IIM, slow-tonic and slow-twitch fibres, but in the Old World monkeys it resembled stapedius muscle, and contained only Type I (slow-twitch) and IIA fibres. Thus, because all the species examined had IIM fibres in the jaw-closer muscles, this means that the common embryological origin of tensor tympani muscle and the jaw-closers does not necessarily result in tensor tympani muscle containing this fibre type even though IIM fibres occur only in first branchial arch muscles. This fact, together with other species differences in the fibre type composition of these muscles, shows that there is no typical composition of middle ear muscles in general, and suggests that the differences are related to very different functional requirements.

Animals↗
PubMed1982

No classical type IIB fibres in dog skeletal muscle.

To analyse the fibre type composition of adult dog skeletal muscle, enzyme histochemistry, immunohistochemistry for type I, IIA and IIB myosins, and peptide mapping of myosin heavy chains isolated from typed single according to the activity of the m-ATPase after acidic and alkaline preincubation proved to be rather difficult and was only consistently achieved after a very careful adjustment of the systems used. One of these sub-classes of type II fibres stained more strongly for m-ATPase activity after acidic and alkaline preincubation, was oxidative-glycolytic and showed a strong reaction with an anti-type IIA myosin. The other one, however, although showed a faint reaction with an anti-type IIB myosin. Peptide mapping of the myosin heavy chains of typed single fibres revealed two populations of heavy chains among the type II fibre group. Thus, in dog muscle, we are confronted with the presence of two main classes of type II fibres, both oxidative-glycolytic, but differing in the structure of their myosin heavy chains. In contrast to some reports in the literature, no classical type IIB fibres could be detected.

Adenosine Triphosphatases↗
PubMed1982

The tensor tympani muscle of cat and dog contains IIM and slow-tonic fibres: an unusual combination of fibre types.

Using recently developed highly specific antisera to the full range of known adult mammalian skeletal muscle myosins, an immunohistochemical and histochemical examination was made of the middle ear muscle tensor tympani in the dog and cat. Approximately half the fibres were of the IIM type and there was a substantial population of apparently slow-tonic fibres, both these types being rare in mammals. In addition, some type I but no IIA nor IIB fibres were detected. Moreover, as no multiple end-plate innervation, thought to be typical of slow-tonic fibres, could be demonstrated in this muscle by acetylcholinesterase staining or by Ruffini gold impregnation, it is suggested that in tensor tympani the slow-tonic fibres are focally innervated. The very short length of the fibres, only 1-2 mm, is probably sufficient to permit adequate depolarization of a whole fibre by a single centrally situated end-plate. The functional implications of this combination of very rare fibre types in tensor tympani are unclear at present.

Animals↗
PubMed1979

A comparative histochemical study of intrinsic laryngeal muscles of ungulates and carnivores.

The intrinsic laryngeal muscles of the horse, donkey, sheep, ox, pig, dog and cat were examined for myosin ATPase, following acid and alkali pre-incubation, SDH and M-alphaGPDH activities. In all laryngeal muscles two fibre types, betaR and alphaR, belonging to slow and fast-contracting, fatigue-resistant motor units (types S and FR) were present in different proportions. The alphaW fibre type, belonging to fast-contracting and fatigue-resistant motor units was absent (type FF). The alphaR fibres of the dog and the cat were subdivided into groups by the various degrees of acid stable myosin ATPase, oxidative and glycolytic activities. In the ox and pig laryngeal muscles, the same fibres showed an atypical myosin ATPase activity, as high as the fast-contracting fibres but acid-resistant like the slow-twitch fibres. The most uniform muscle was the CAD, which was formed of a higher percentage of slow-twitch fibres than the other laryngeal muscles of the same species. Also the VE muscle was very uniform in the dog, horse and donkey but the fast-twitch fibres were by far the most numerous, the highest in fact among all the laryngeal muscles. In the TA muscle of the cat, sheep and ox, the percentage of fast-twitch fibres was very high in the rostral portion decreasing gradually towards the caudal portion. Thus it was possible to separate histochemically the TA muscle in the rostral (pars ventricularis) and caudal (pars vocalis) portions which are related to the VE and the VO muscles of the dog, horse and donkey. In the VO muscle the slow-twitch fibres are more numerous than in the VE. The two portions of the TA were not detected by histochemical methods in the pig. However, this muscle has the highest percentage of fast-twitch fibres. The qualitative and quantitative data presented in this paper together with the data reported in the literature, enable us to correlate morphological and functional aspects of fibre composition among the species.

Animals↗
PubMed1977

Experimental arthrosis from intra-articular vitamin A injection in the rabbit. Morphological and biochemical study: considerations on the pathogenesis of human arthrosis in relation to the experimental model.

The key to the pathogenesis of arthrosis lies in the mechanism responsible for the initial lesions. In this experimental work the possibility of producing arthrosic changes is demonstrated by activating lysosomal chondrocytic enzymes by the intra-articular injection of Vitamin A in rabbits. On the basis of the experimental results the authors discuss the possible role that activation of the lysosomal hydrolytic enzymes might play in producing primary and secondary arthrosis in humans. They advance the hypothesis that this mechanism may be the common final step in the degradation of the articular cartilage, whatever the aetiological factor.

Acid Phosphatase↗