Histochemical characterization of the red fibres in pigeon pectoralis muscle.

Red fibres of the pigeon pectoralis muscle showed high ATPase reaction at pH 9.4. Veronal-acetate pretreatment completely inhibited the ATPase reaction in these red fibres but not in type I fibres of the gastrocnemius. The former are type II red muscle fibres and hence are unlike type I red, the so-called slow-twitch muscle fibres.     

Histochemical characterization of the red fibres in pigeon pectoralis muscle

Summary Red fibres of the pigeon pectoralis muscle showed high ATPase reaction at pH 9.4. Veronal-acetate pretreatment completely inhibited the ATPase reaction in these red fibres but not in type I fibres of the gastrocnemius. The former are type II red muscle fibres and hence are unlike type I red, the so-called slow-twitch muscle fibres.     

Immunocytologic differentiation of hypophyseal innervation in carp using anti met-enkephalin and anti-alpha-endorphin serums]

The immunocytological reactions with anti-met-enkephalin and anti-alpha-endorphin reveal two types of fibres in the intermediate lobe of the Carp. Their pathways through the adenohypophysis and the localization of their terminals are different. The anti-met-enkephalin positive fibres terminate mainly in a zone close to the proximal pars distalis; however some fibres terminate deeper in the intermediate lobe. The anti-alpha-endorphin positive fibres penetrate mainly in the central and ventral part where thye are more numerous than the former. It seems that the anti-met-enkephalin positive fibres belong to the gomori positive preoptico-hypophyseal tract, whereas the anti-alpha-endorphin positive fibres are gomori negative.     

Variation in the number and size of myelinated nerve fibers regenerated after repeated localized freezing of the sciatic nerve of rats]

The number and size of myelinated fibres have been determined in the nerve to medial head of the gastrocnemius muscle of Rats in which the sciatic nerve had been frozen locally 1 to 5 times at monthly intervals. The contralateral nerve was used as a control. When the measurements were made one month after the last freezing, the number of fibres increased progressively until the 3rd freezing, reaching about 220% of the normal value. No higher values were observed after 4 or 5 freezings. The mean diameter of fibres decreased with the number of operations. When the measurements were made 3, 6, 12 or 18 months after the 3rd freezing, the number of fibres decreased by about 30% between the 1st and the 3rd month and then stabilized. The mean diameter of fibres increased progressively. However, at the 18th month, the size of the myelinated fibres had not reached the normal value.     

The process of survival of denervated and freely autotransplantated skeletal muscle.

The study shows that two distinct processes occur in free autografts of denervated intact muscle during the early critical phase of the transplantation: survival of transplanted fibres at the periphery of the graft, and regeneration of new muscle fibres following breakdown of the originally transplanted fibres in the central areas.     

Structural changes of deoxyribonucleoprotein fibres following gamma-irradiation under aerobic and hypoxic conditions.

The DNP fibres gamma-irradiated under aerobic condition showed a reduction of their diameter, while no remarkable changes were observed in the DNP fibres irradiated under hypoxic condition by scanning electron microscopy.     

Das Spitzenwachstum der Fasern beiLinum perenne L

Summary In shoots ofLinum perenne apical growth was observed at both ends of the fibres. Their rounded tips, rich in protoplasm, protude into the middle lamellae of adjacent fibres or parenchyma cells. In addition to their apical growth, the fibre walls undergo symplastic growth with the walls of neighbouring cells. The formation of the pointed ends of fully developed fibres is described.     

A histochemical study of denervated marsupial hemidiaphragm.

The marsupial (quokka) hemidiaphragm showed postdenervation hypertrophy and subsequent atrophy. The type II muscle fibres hypertrophied up to 20 days postoperation and then regressed. However, the type I fibres hypertrophied throughout the experimental period (100 days) studied. Unlike denervated eutherian hemidiaphragm, fibre-splitting was absent in the denervated marsupial muscle. An enhancement of the ATPase reaction in the denervated type I fibres may be due to dedifferentiation. Presumably innervation exerts a 'negative control' and prevents increase of type I fibre size in the normal hemidiaphragm.     

Histochemical demonstration of differences in AMP deaminase activity in rat skeletal muscle-fibres

The histochemical method for AMP deaminase confirms that rat slow-twitch fibres contain less AMP deaminase activity than fast-twitch fibres. However, the enzyme appears similarly localized in all fibre types.     

Histochemical demonstration of differences in AMP deaminase activity in rat skeletal muscle-fibres

Summary The histochemical method for AMP deaminase confirms that rat slow-twitch fibres contain less AMP deaminase activity than fast-twitch fibres. However, the enzyme appears similarly localized in all fibre types.This study was supported by NIH grant AM 21617.     

Pathways for excitatory and inhibitory innervation to the guinea-pig tracheal smooth muscle.

The trachea receives excitatory cholinergic innervation from the vagus nerve and the stellate ganglion. Inhibitory adrenergic fibres have the same sources. Those in the vagus nerve probably derive from high vagosympathetic anastomoses. Nonadrenergic inhibitory fibres have a preganglionic vagal supply.     

Elaunin fibres in the basement membrane of sweat gland secretory coil are rich in disulfide-groups.

Disulfide-groups of elaunin fibres of sweat gland basement membrane are demonstrated a) by thiosulfation/aldehyde-fuchsin staining or thiosulfation/Alcian Blue + 0.8 M MgCl2 staining, and b) by identifying SH-groups after reduction with sodiumthioglycollate. Elaunin fibres share this staining behaviour with "elastic fibre microfibrils" and with oxytalan fibres.     

Endothelial nerve fibres in the cornea of the frogRana ridibunda

Summary The ultrastructural study of the frog cornea revealed the existence of intraendothelial nerve fibres. These nerve fibres are unmyelinated elements but surrounded by cytoplasmic lamellae of Schwann cells.Supported by D.C.I.N.P. Grant 78-77.     

A histochemical study of the pectoralis muscle of the south indian flying lizard,Draco dussumieri

Résumé Le muscle pectoral duDraco dussumieri comprend des fibres de trois sortes: minces, intermédiaires et épaisses. Les fibres minces sont adaptées à un métabolisme glycolytique et les fibres épaisses au lipolytique. L'activité des fibres minces révèle la présence de phosphorylase et de synthétase glycogénique.     

Coordinated activation of muscle fibres by different conduction velocities in branches of a crustacean motor axon

Summary Higher conduction velocities in branches of the fast excitor axon to distal muscle fibres ensure that these fibres are activated almost simultaneously with proximal fibres in the claw closer muscle of lobsters, producing a contraction of maximal force.Supported by Muscular Dystrophy Association and National Research Council of Canada.Supported by National Institute of Health and Muscular Dystrophy Association of America.     

Spontaneous miniature potentials in primary afferent fibres

Summary Intracellular recording from primary afferent fibres of the isolated frog spinal cord revealed the existence of spontaneous synaptic activity, related probably to the firing of presynaptic inhibitory fibres.     

Effect of glycerol treatment on sodium and potassium in isolated muscle fibres of the frog

Summary The sodium concentration in single frog muscle fibres vacuolated by glycerol treatment was significantly higher than in devacuolated fibres. Intracellular potassium concentration did not show any significant change. It is concluded that the transverse tubular system forms vacuoles with a high NaCl concentration upon glycerol removal.     

On the heterogeneity of skeletal muscle fibers: The intermediate fibers

Résumé Les mesures d'intensité de la réaction à la succino-déshydrogénase et de la surface des fibres des muscles quadriceps et soléaire chez le rat nous ont permis d'individualiser un groupe de fibres intermédiaires qui se situe entre les fibres rouges (type I) et blanches (type II). Les fibres intermédiaires ont une activité enzymatique et une population mitochondriale distinctes, une taille moyenne et une teneur élevée en glycogène.     

A vital stain for the specialized tissues of the heart

Résumé On constate que certaines fibres sous l'action du méthylène bleu présentent une coloration accentuée. Une proportion importante de ces fibres ont des fonctions apparemment spécialisées. Les fibres teintes ont gardé apparemment leur ultrastructure et leur fonction.     

Spontaneous miniature potentials in primary afferent fibres.

Intracellular recording from primary afferent fibres of the isolated frog spinal cord revealed the existence of spontaneous synaptic activity, related probably to the firing of presynaptic inhibitory fibres.