The innervation pattern of fast myotomal muscle in the teleostMyoxocephalus scorpius: A reappraisal

To delineate what modifications in muscle metabolic biochemistry correlate with transition to air breathing in fishes, the myotomal muscles of aruana, an obligate water breather, and Arapaima, a related obligate air breather, were compared using electron microscopy and enzyme methods. White muscle in both species maintained a rather similar ultrastructure, characterized by large-diameter fibers, very few mitochondria, and few capillaries. However, aruana white muscle displayed nearly fivefold higher levels of pyruvate kinase, threefold higher levels of muscle-type lactate dehydrogenase, and a fourfold higher ratio of fructose diphosphatase –phosphofructokinase activity; at the same time, enzymes in aerobic metabolism occurred at about one-half the levels in Arapaima. Red muscle was never found in the myotomal mass of aruana, but in Arapaima, red muscle was present and seemed fueled by glycogen, lipid droplets never being observed. From these and other data, it was concluded that in myotomal muscle two processes correlate with the transition to air breathing in Amazon osteoglossids: firstly, an emphasis in oxidative metabolism, and secondly, a retention of red muscle. However, compared with more active water-breathing species, Arapaima sustains an overall dampening of enzyme activities in its myotomal muscle, which because of the large myotome mass explains why its overall metabolic rate is relatively low. By keeping the oxidative capacity of its myotomal muscle low, Arapaima automatically conserves O2 either for a longer time or for other more O2-requiring organs in the body, a perfectly understandable strategy for an air-breathing, diving fish, comparable with that observed in other diving vertebrates. A similar comparison was also made of two erythrinid fishes, one that skimmed the O2-rich surface layers of water and one that obtained three quarters of its O2 from water, one quarter from air. Ultrastructural and enzyme data led to the unexpected conclusion that the surface skimmer sustained a higher oxidative capacity in its myotomal muscles than did the facultative air breather.

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Chronic Paroxysmal Hemicrania: Salivation, Tearing and Nasal Secretion

Cephalalgia ◽

10.1046/j.1468-2982.1984.0401025.x ◽

1984 ◽

Vol 4 (1) ◽

pp. 25-32 ◽

Cited By ~ 6

Author(s):

C Saunte

Keyword(s):

Salivary Glands ◽

Nasal Secretion ◽

Test Battery ◽

The Other ◽

Paroxysmal Hemicrania ◽

Control Group ◽

Innervation Pattern ◽

Autonomic Functions ◽

Chronic Paroxysmal Hemicrania ◽

The One

Autonomic functions have been studied in seven patients with chronic paroxysmal hemicrania (CPH). A test battery comprising tearing, salivation and nasal secretion was employed. Under basal conditions these parameters did not differ significantly from those in a control group. After stimulation with pilocarpine the patients responded rather inhomogeneously. This test battery may therefore help find and classify subgroups of these types of patients. During attacks, there is a clear discrepancy between minimal salivation on the one hand and the marked increase in tearing, nasal secretion and sweating on the other. CPH attacks may be associated with an increased firing of sympathetic impulses to the different organs. In the event of a uniform type of autonomic firing taking place during attack, these findings may suggest a different innervation pattern for the salivary glands compared to the other glands involved. The innervation pattern of these secretory organs may seem to be more intricate and sophisticated than hitherto assumed.

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EFFICIENCY OF ENERGY CONVERSION DURING SINUSOIDAL MOVEMENT OF WHITE MUSCLE FIBRES FROM THE DOGFISH SCYLIORHINUS CANICULA

Journal of Experimental Biology ◽

10.1242/jeb.183.1.137 ◽

1993 ◽

Vol 183 (1) ◽

pp. 137-147 ◽

Cited By ~ 9

Author(s):

N. A. Curtin ◽

R. C. Woledge

Keyword(s):

Power Output ◽

High Efficiency ◽

Fibre Length ◽

Dry Mass ◽

Energy Output ◽

Maximum Efficiency ◽

Muscle Fibres ◽

Work Output ◽

Sinusoidal Movement ◽

Myotomal Muscle

Net work output and heat production of white myotomal muscle fibres from the dogfish were measured during complete cycles of sinusoidal movement at 12°C. The peak-to-peak movement was about 9 % of the muscle fibre length; three stimuli at 32 ms intervals were given in each mechanical cycle. The frequency of movement and the timing of the stimulation were varied for each preparation to find the optimal conditions for power output and those optimal for efficiency (the ratio of net work output to total energy output as heat+work). To achieve either maximum power or maximum efficiency, the tetanus must start while the muscle fibres are being stretched, before the beginning of the shortening part of the mechanical cycle. The highest power output, averaged over one cycle, was 0.23+/−0.014 W g-1 dry mass (+/−s.e.m., N=9, 46.9+/−2.8 mW g-1 wet mass) and was produced during movement at 3.5 Hz. The highest efficiency, 0.41+/−0.02 (+/−s.e.m., N=13), occurred during movements at 2.0-2.5 Hz. This value is higher than the efficiency previously measured during isovelocity shortening of these fibres. The implications of the high efficiency for crossbridge models of muscle contraction are discussed.

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Induction of acetylcholine receptor clustering by native polystyrene beads. Implication of an endogenous muscle-derived signalling system

Journal of Cell Science ◽

10.1242/jcs.102.3.543 ◽

1992 ◽

Vol 102 (3) ◽

pp. 543-555 ◽

Cited By ~ 2

Author(s):

L.P. Baker ◽

Q. Chen ◽

H.B. Peng

Keyword(s):

Growth Factor ◽

Cell Surface ◽

Acetylcholine Receptor ◽

Hot Spots ◽

Hot Spot ◽

Muscle Cells ◽

Membrane Receptors ◽

Heparin Binding ◽

Polystyrene Beads ◽

Myotomal Muscle

Aneural muscle cells in culture often form acetylcholine receptor (AChR) clusters, termed hot spots, which are similar to those found at the postsynaptic membrane both in structure and in molecular composition. Although hot spots form on both dorsal and ventral surfaces of the cell, the ventral ones are better characterized because of their association with sites of cell-substratum contact. To understand the stimuli and mechanisms involved in ventral hot spot formation, native, uncoated polystyrene beads were applied to cultured Xenopus myotomal muscle cells to create local membrane-substratum contacts. These beads were able to induce a postsynaptic-type development as evidenced by the clustering of AChRs and the development of a set of ultrastructural specializations, including membrane infoldings and a basement membrane. Whereas these native beads were effective in inducing clustering, beads coated with bovine serum albumin or treated with serum-containing medium were ineffective. Native beads were also capable of inducing clusters in serum-free medium, indicating that their effect was mediated by endogenous molecules that were locally presented by the beads, rather than by bead adsorption of components in the medium. Heparan sulfate proteoglycan (HSPG) is a major component of the muscle extracellular matrix and our previous study has shown that basic fibroblast growth factor (bFGF), a member of the heparin-binding growth factor (HBGF) family, and its receptor are present in Xenopus myotomal muscle during the period of synaptogenesis. Therefore, we tested the involvement of HBGF in bead induction. The results of this study show the following: (1) preincubation of cultures in heparin, which solubilizes matrix-bound HBGFs, suppressed the bead-induced AChR clustering. (2) Suramin, which interferes with the interaction between several growth factors and their receptors, also inhibited bead-induced clustering. (3) Tyrphostin, which blocks tyrosine kinase activity associated with a number of growth factor receptors, was also inhibitory to the bead effect. (4) The percentage of bead-induced AChR clusters was significantly enhanced by pretreating the cultures with bFGF prior to bead application. This exogenously applied bFGF could be largely removed by treatment of cultures with heparin, suggesting its association with HSPG at the cell surface. (5) An anti-bFGF neutralizing antiserum significantly reduced the efficacy of the bead stimulation. These data suggest that uncoated beads, which adhere to the cell surface and can mimic the cell-substratum interaction, effect a local presentation of HBGFs, such as bFGF, residing with the HSPG to their membrane receptors, thereby locally activating receptor-associated tyrosine kinases.(ABSTRACT TRUNCATED AT 400 WORDS)

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Fate of brachial muscles of the chick embryo innervated by inappropriate nerves: structural, functional and histochemical analyses

Development ◽

10.1242/dev.95.1.147 ◽

1986 ◽

Vol 95 (1) ◽

pp. 147-168

Author(s):

Jane Butler ◽

Peter Cauwenbergs ◽

Ethel Cosmos

Keyword(s):

Chick Embryo ◽

Muscle Growth ◽

Extended Period ◽

Differential Rate ◽

Innervation Pattern ◽

In Ovo ◽

Intramuscular Nerve ◽

Quantitative Analyses ◽

Wing Bud ◽

Actual Loss

The extent of interaction between brachial muscles and foreign (thoracic) nerves of the chick embryo was determined during an extended period of development in ovo from the perspectives of innervation pattern, function (motility analyses), muscle growth (quantitative analyses of muscle volume) and fibre-type expression (myosin-ATPase profiles). Results indicated that according to all parameters analysed, initially a compatible union existed between the foreign nerves and their muscle targets. During subsequent stages of development, deterioration of the once compatible relationship emerged, until eventually denervation of muscles, i.e. an actual loss of intramuscular nerve branches, was observed. The process of denervation, which proceeded at a differential rate among individual muscles, however was restricted to brachial muscles derived from the premuscle masses of the wing bud. In contrast, brachial muscles of myotomal origin were spared the fate of wing-bud-derived muscles and maintained a successful union with the foreign nerves.

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Autonomic Disorders in Cluster Headache, With Special Reference to Salivation, Nasal Secretion and Tearing

Cephalalgia ◽

10.1046/j.1468-2982.1984.0401057.x ◽

1984 ◽

Vol 4 (1) ◽

pp. 57-64 ◽

Cited By ~ 21

Author(s):

C Saunte

Keyword(s):

Cluster Headache ◽

Special Reference ◽

Nasal Secretion ◽

Test Battery ◽

Innervation Pattern ◽

Autonomic Disorders ◽

Symptomatic Side

Attacks of cluster headache are often associated with symptoms of an autonomic nature. A test battery allowing quantitation of salivation, nasal secretion and tearing has been employed. Fourteen patients examined under basal conditions hardly differed from a group of controls (N = 20). After stimulation with pilocarpine the patients responded like the controls. During attacks we found minimal bilateral salivation, but an increase of tearing and nasal secretion, mostly on the symptomatic side. These results correspond with those found in CPH. The finding of the minimal salivation is consistent with the notion that the headache attacks are associated with increased sympathico-tonus. The results may suggest that the complexity of the innervation pattern of the different secretory organs examined is more marked than hitherto known.

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The effects of environmental temperature on the properties of myofibrillar adenosine triphosphatase from various species of fish

Biochemical Journal ◽

10.1042/bj1330735 ◽

1973 ◽

Vol 133 (4) ◽

pp. 735-738 ◽

Cited By ~ 72

Author(s):

Ian A. Johnston ◽

Neil Frearson ◽

Geoffrey Goldspink

Keyword(s):

Low Temperatures ◽

Half Life ◽

Adenosine Triphosphatase ◽

Environmental Temperature ◽

Cold Water ◽

Warm Water ◽

Adenosine Triphosphatase Activity ◽

Water Fish ◽

Different Temperatures ◽

Myotomal Muscle

1. Myofibrillar adenosine triphosphatase (ATPase) activities were measured for white myotomal muscle of 19 species of fish. 2. The activity was measured at different temperatures and after periods of preincubation at 37°C. 3. The inactivation half-life at 37°C depended on environmental temperature, increasing as the temperature increased. 4. Cold-water fish had higher myofibrillar adenosine triphosphatase activity at low temperatures than had warm-water fish. 5. The significance of these results is discussed.

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