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Li H, Staxäng K, Hodik M, Melkersson KG, Rask-Andersen M, Rask-Andersen H. Regeneration in the Auditory Organ in Cuban and African Dwarf Crocodiles (Crocodylus rhombifer and Osteolaemus tetraspis) Can We Learn From the Crocodile How to Restore Our Hearing? Front Cell Dev Biol 2022; 10:934571. [PMID: 35859896 PMCID: PMC9289536 DOI: 10.3389/fcell.2022.934571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2022] [Accepted: 06/08/2022] [Indexed: 11/16/2022] Open
Abstract
Background: In several non-mammalian species, auditory receptors undergo cell renewal after damage. This has raised hope of finding new options to treat human sensorineural deafness. Uncertainty remains as to the triggering mechanisms and whether hair cells are regenerated even under normal conditions. In the present investigation, we explored the auditory organ in the crocodile to validate possible ongoing natural hair cell regeneration. Materials and Methods: Two male Cuban crocodiles (Crocodylus rhombifer) and an adult male African Dwarf crocodile (Osteolaemus tetraspis) were analyzed using transmission electron microscopy and immunohistochemistry using confocal microscopy. The crocodile ears were fixed in formaldehyde and glutaraldehyde and underwent micro-computed tomography (micro-CT) and 3D reconstruction. The temporal bones were drilled out and decalcified. Results: The crocodile papilla basilaris contained tall (inner) and short (outer) hair cells surrounded by a mosaic of tightly connected supporting cells coupled with gap junctions. Afferent neurons with and without ribbon synapses innervated both hair cell types. Supporting cells occasionally showed signs of trans-differentiation into hair cells. They expressed the MAFA and SOX2 transcription factors. Supporting cells contained organelles that may transfer genetic information between cells, including the efferent nerve fibers during the regeneration process. The tectorial membrane showed signs of being replenished and its architecture being sculpted by extracellular exosome-like proteolysis. Discussion: Crocodilians seem to produce new hair cells during their life span from a range of supporting cells. Imposing efferent nerve fibers may play a role in regeneration and re-innervation of the auditory receptors, possibly triggered by apoptotic signals from wasted hair cells. Intercellular signaling may be accomplished by elaborate gap junction and organelle systems, including neural emperipolesis. Crocodilians seem to restore and sculpt their tectorial membranes throughout their lives.
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Affiliation(s)
- Hao Li
- Department of Surgical Sciences, Head and Neck Surgery, Section of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
| | - Karin Staxäng
- The Rudbeck TEM Laboratory, BioVis Platform, Uppsala University, Uppasala, Swedan
| | - Monika Hodik
- The Rudbeck TEM Laboratory, BioVis Platform, Uppsala University, Uppasala, Swedan
| | | | - Mathias Rask-Andersen
- Department of Immunology, Genetics and Pathology, Science for Life Laboratory, Uppsala University, Uppsala, Sweden
| | - Helge Rask-Andersen
- Department of Surgical Sciences, Head and Neck Surgery, Section of Otolaryngology, Uppsala University Hospital, Uppsala, Sweden
- *Correspondence: Helge Rask-Andersen,
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Plotnikov SV, Kenny AM, Walsh SJ, Zubrowski B, Joseph C, Scranton VL, Kuchel GA, Dauser D, Xu M, Pilbeam CC, Adams DJ, Dougherty RP, Campagnola PJ, Mohler WA. Measurement of muscle disease by quantitative second-harmonic generation imaging. JOURNAL OF BIOMEDICAL OPTICS 2008; 13:044018. [PMID: 19021346 DOI: 10.1117/1.2967536] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Determining the health of muscle cells by in vivo imaging could impact the diagnosis and monitoring of a large number of congenital and acquired muscular or cardiac disorders. However, currently used technologies are hampered by insufficient resolution, lack of specificity, or invasiveness. We have combined intrinsic optical second-harmonic generation from sarcomeric myosin with a novel mathematical treatment of striation pattern analysis, to obtain measures of muscle contractile integrity that correlate strongly with the neuromuscular health of mice suffering from genetic, acquired, and age-related decline in skeletal muscle function. Analysis of biopsies from a pilot group of human volunteers suggests a similar power in quantifying sarcopenic changes in muscle integrity. These results provide the first strong evidence that quantitative image analysis of sarcomere pattern can be correlated with physiological function, and they invite the application of SHG imaging in clinical practice, either in biopsy samples or via microendoscopy.
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Affiliation(s)
- Sergey V Plotnikov
- University of Connecticut Health Center, Department of Genetics and Developmental Biology, Farmington, Connecticut 06030, USA
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Plotnikov S, Juneja V, Isaacson AB, Mohler WA, Campagnola PJ. Optical clearing for improved contrast in second harmonic generation imaging of skeletal muscle. Biophys J 2005; 90:328-39. [PMID: 16214853 PMCID: PMC1367031 DOI: 10.1529/biophysj.105.066944] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Using second harmonic generation (SHG) imaging microscopy, we have examined the effect of optical clearing with glycerol to achieve greater penetration into specimens of skeletal muscle tissue. We find that treatment with 50% glycerol results in a 2.5-fold increase in achievable SHG imaging depth. Signal processing analyses using fast Fourier transform and continuous wavelet transforms show quantitatively that the periodicity of the sarcomere structure is unaltered by the clearing process and that image quality deep in the tissue is improved with clearing. Comparison of the SHG angular polarization dependence also shows no change in the supramolecular organization of acto-myosin complexes. By contrast, identical treatment of mouse tendon (collagen based) resulted in a strong decrease in SHG response. We suggest that the primary mechanism of optical clearing in muscle with glycerol treatment results from the reduction of cytoplasmic protein concentration and concomitant decrease in the secondary inner filter effect on the SHG signal. The lack of glycerol concentration dependence on the imaging depth indicates that refractive index matching plays only a minor role in the optical clearing of muscle. SHG and optical clearing may provide an ideal mechanism to study physiology in highly scattering skeletal or cardiac muscle tissue with significantly improved depth of penetration and achievable imaging depth.
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Affiliation(s)
- Sergey Plotnikov
- Department of Genetics and Developmental Biology, University of Connecticut Health Center, Farmington, Connecticut 06030, USA
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Rumyantsev PP, Krylova MI. Ultrastructure of myofibers and cells synthesizing DNA in the developing and regenerating lymph-heart muscles. INTERNATIONAL REVIEW OF CYTOLOGY 1990; 120:1-52. [PMID: 2406211 DOI: 10.1016/s0074-7696(08)61598-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- P P Rumyantsev
- Institute of Cytology of the Academy of Sciences of the U.S.S.R., Leningrad
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Aldoroty RA, Garty NB, April EW. Donnan potentials from striated muscle liquid crystals. Lattice spacing dependence. Biophys J 1987; 51:371-81. [PMID: 3567311 PMCID: PMC1329903 DOI: 10.1016/s0006-3495(87)83359-3] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Electrochemical potentials were measured as a function of myofilament packing density in crayfish striated muscle. The A-band striations are supramolecular smectic B1 lattice assemblies of myosin filaments and the I-band striations are nematic liquid crystals of actin filaments. Both A- and I-bands generate potentials derived from the fixed charge that is associated with structural proteins. In the reported experiments, filament packing density was varied by osmotically reducing lattice volume. The electrochemical potentials were measured from the A- and I-bands in the relaxed condition over a range of lattice volumes. From the measurements of relative cross-sectional area, unit-cell volume (obtained by low-angle x-ray diffraction) and previously determined effective linear charge densities (Aldoroty, R.A., N.B. Garty, and E.W. April, 1985, Biophys. J., 47:89-96), Donnan potentials can be predicted for any amount of compression. In the relaxed condition, the predicted Donnan potentials correspond to the measured electrochemical potentials. In the rigor condition, however, a net increase in negative charge associated with the myosin filament is observed. The predictability of the data demonstrates the applicability of Donnan equilibrium theory to the measurement of electrochemical potentials from liquid-crystalline systems. Moreover, the relationship between filament spacing and the Donnan potential is consistent with the concept that surface charge provides the necessary electrostatic force to stabilize the myofilament lattice.
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Fan SF, Dewey M, Colflesh D, Chu B. The effects of deuterium oxide on the active cross-bridge motion of thick filaments isolated from striated muscle of Limulus. ACTA ACUST UNITED AC 1985. [DOI: 10.1016/0167-4838(85)90291-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Campo ML, Tedeschi H. Protonmotive force and photophosphorylation in single swollen thylakoid vesicles. EUROPEAN JOURNAL OF BIOCHEMISTRY 1985; 149:511-6. [PMID: 2988949 DOI: 10.1111/j.1432-1033.1985.tb08954.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Swollen vesicles generally 40 micron in diameter were prepared from spinach chloroplasts. These vesicles appear to originate from thylakoids. The present study reports results obtained with individual vesicles using micromanipulative procedures. The electric potential across the membrane was measured with microelectrodes and the pH of the internal space was calculated from the fluorescence of the pH indicator pyranine. The individual vesicles photophosphorylate as measured with luciferin-luciferase. Impalement with microelectrodes did not affect the ability of individual vesicles to photophosphorylate. However, there was no significant membrane potential either with continuous illumination or light flashes. In contrast, we found a delta pH of 3.7 under photophosphorylative conditions and the incubation with the appropriate buffers blocked photophosphorylation presumably by preventing formation of a pH gradient. We propose that, in these vesicles, the membrane potential plays no role in photophosphorylation, whereas a pH gradient is obligatory.
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Aldoroty RA, April EW. Donnan potentials from striated muscle liquid crystals. A-band and I-band measurements. Biophys J 1984; 46:769-79. [PMID: 6518255 PMCID: PMC1435105 DOI: 10.1016/s0006-3495(84)84075-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
A-band and I-band potentials are measured selectively in crayfish skinned long-tonic muscle fibers. The microelectrode tip diameters used in this study are shown to be sufficiently small to permit the discrete placement of an electrode into either an A-band or I-band. Random and directed impalements into mechanically skinned fibers with microelectrodes yields reproducible trimodal distributions of potentials where the modalities represent the A-band (-1.80 mV), the I-band (-0.76 mV), and the Z-line vicinity (-3.63 mV). In conjunction with Donnan equilibrium theory, fixed charge concentrations are calculated from the measured potentials for the A-band (25.9 mmol e-/l), I-band (10.9 mmol e-/l), and Z-line vicinity (52.3 mmol e-/l). When skinned fibers are treated with Triton X-100, the mean potentials (and charge concentrations) decrease: A-band to -1.71 mV (24.6 mmol e-/l), I-band to -0.71 mV (10.2 mmol e-/l), and the Z-line vicinity to -3.40 mV (49.0 mmol e/l). In the A-band this represents a loss of 1.3 mmol e-/l while in the I-band 0.7 mmol e-/l are lost; both decreases are attributed to the removal of internal membranous structures. In the rigor condition the A-band increases to -2.18 mV (33.1 mmol e-/l) and the I-band increases to -0.88 mV (13.3 mmol e-/l). Relative to the relaxed condition, this represents an increase of 8.5 mmol e-/l and 3.1 mmol e-/l in the A-band and I-band, respectively. The evidence shows that it is practical to measure A-band and I-band potentials selectively. Further, it is demonstrated that similar measurements can be obtained from agar, another polyelectrolyte gel system (see Appendix).
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Godt RE, Baumgarten CM. Potential and K+ activity in skinned muscle fibers. Evidence against a simple Donnan equilibrium. Biophys J 1984; 45:375-82. [PMID: 6230113 PMCID: PMC1434854 DOI: 10.1016/s0006-3495(84)84161-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
It has been suggested that potentials measured with conventional microelectrodes in chemically or mechanically skinned muscle fibers arise from a Donnan equilibrium due to myofilament fixed charges. This hypothesis was tested in mechanically skinned frog (Rana pipiens) semitendinosus fibers by measuring the distribution potential (Ed) between fiber and bath with 3 M KCl-filled microelectrodes and the K+ activity gradient (aik/aok) with K+ ion-selective microelectrodes (KISE). If skinned fibers are a Donnan system, Ed should become more positive as pH is decreased, altering the fixed charge on the myofilaments. Consistent with this expectation, Ed was -4.4, -0.6, and +4.8 mV in ATP-containing solutions and -6.5, -2.2, and +8.4 mV in ATP-free solutions at pH 7, 6, and 5, respectively. Donnan equilibrium also requires that all mobile ionic species be in electrochemical equilibrium. In ATP-containing solutions, this was true for K+ at pH 7. At pH 5, however, KISE indicated that K+ was not in equilibrium; average Ed was 5.9 mV positive to the K+ equilibrium potential, and aik/aok was 1.04, while the Donnan prediction was 0.83. In contrast, KISE measurements in ATP-free solutions indicated that K+ was in equilibrium at all pH studied. Skinned fibers in ATP-containing media are not equilibrium systems because ATPase reactions occur. Under our conditions, frog myofibrils hydrolyze 0.4 and 0.08 mumol ATP/min X mg myofibrillar protein at pH 7 and 5, respectively. It is suggested that in the presence of ATP, Ed is a superposition of Donnan and diffusion potentials, the latter arising from differences in the mobilities of anionic substrate and products that diffuse through the charged myofilament lattice. A coupling to diffusion of K+, the predominant counter ion, is required for macroscopic electroneutrality. This coupling may be the origin of the nonequilibrium K+ distribution.
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McDonnell TJ, Oberpriller JO. The ultrastructure of the atrium in the adult newtNotophthalmus viridescens (Amphibia, Salamandridae). J Morphol 1983; 175:235-251. [DOI: 10.1002/jmor.1051750303] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Caillé JP. The myoplasmic fixed charges of the barnacle muscle fiber and the free Ca2+ concentration. BIOCHIMICA ET BIOPHYSICA ACTA 1981; 673:416-24. [PMID: 7225424 DOI: 10.1016/0304-4165(81)90473-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
An experimental model was recently developed to measure the myoplasm density of fixed charges (Caillé J.P. (1979) Biochim. Biophys. Acta 585, 300-313). The effect of ATP, Mg2+ and Ca2+ suggests that the myoplasmic thermodynamically effective charge density (phi X) decreases during muscular contraction. In order to determine if this reduction was due to either ATP, Mg2+ or Ca2+, the phi X dependence on those substances was studied. The results indicated that the addition of MgCl2 (2 mM) reduced phi X by 10 to 30% depending on the water content of the myoplasm. A reduction of phi X was also observed with the addition of (10(-4) M) Ca2+, but the presence of ATP was necessary for this reduction to occur. Finally when EGTA was added to the external solution in order to control the level of free Ca2+, an important reduction of phi X (40%) was observed for a pCa equal to 5.7 (water content 76.1 +/- 0.3 ml/100 g). These results allowed a correlation between the reduction of the myoplasmic fixed charges and the turning on of the contractile machinery.
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Iijima T, Wasano T. Further studies on catecholamine-containing specific endothelial granules in carp cerebral veins. A fluorescence histochemical and electron microscopy study. Anat Rec (Hoboken) 1980; 198:415-20. [PMID: 7457935 DOI: 10.1002/ar.1091980303] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The effects of noradrenaline (NA), L-3, 4-dihydroxyphenylalanine (L-DOPA), 5-hydroxydopamine (5-OHDA), 6-hydroxydopamine (6-OHDA), and reserpine (RES) on the uptake, accumulation, and release of amines in catecholamine-containing specific endothelial granules (SEG) of carp cerebral veins and their mode of formation were examined by fluorescence histochemistry and electron microscopy. The intramuscular injection of NA (4 mg/kg) or L-DOPA (200 mg/kg) resulted in an increase in both the fluorescence and electron density of SEG. After the administration of false neurotransmitters. 5-OHDA (190 mg/kg) or 6-OHDA (200 mg/kg), the venous endothelial fluorescence almost completely disappeared but the SEG electron density increased. Following the injection of RES (15 mg/kg), the fluorescence intensity and SEG electron density showed no sign of decrease, as was expected, but in fact increased. It is suggested that the SEG are able to take up and accumulate exogeneous amines and that these mechanisms are RES-resistant. The electron density of SEG increased in proportion to the amount of amines in the SEG. The swelling and fragmentation of rough endoplasmic reticulum cisternae and the accumulation of dense material within the cisternae suggests the possible participation of these organelles in SEG formation.
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Katona E, Mărgineanu DG, Vasilescu V. Water compartments in living, glycerinated and fixed skeletal muscles of the frog. Cell Tissue Res 1979; 203:331-8. [PMID: 117897 DOI: 10.1007/bf00237247] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The kinetics of water replacement with heavy water (deuterium oxide) in the gastrocnemius and sartorius muscles of the frog under isotonic conditions, studied both gravimetrically and by infrared photometry, reveals three water compartments: (i) non-exchangeable (approximately 80 ml/kg fresh weight), (ii) slowly exchanging (approximately 500 ml/kg fresh weight), (iii) rapid exchanging--extracellular (approximately 200 ml/kg fresh weight). Exposure to both glycerol and glutaraldehyde increases the permeability coefficients and the amount of rapid exchanging water; glutaraldehyde also increases the amount of non-exchangeable water. Approximately 90% of the water is kept in the tissue only by weak intermolecular forces, the energies of which amount to 1 kcal/mol. The amount of non-exchangeable water is equivalent to about six continuous adsorption layers covering the myofilaments. Approximately 70% of the tissue water appears to be replaced by glutaraldehyde during standard fixation.
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Abstract
Pieces of hearts from adult newts were cultured up to 2 months. Within 7 days of culture, approximately 37% of the cardiac explants were attached to the substrate and more than 33% of the attached explants and approximately 15% of the unattached explants established pulsation rates ranging from 3 to 67 beats/min. The control and cultured explants were processed at weekly intervals for electron microscopy. The diameter of the control cardiac muscle cells ranged approximately 3-5 micron. The cell surface was provided with microvilli. The intercellular spaces ranged approximately 150-500 A. The intercalated discs lacked the step-like courses observed in the mammalian cardiac muscle. Sarcoplasmic reticulum was scanty. Desmosomal-dense materials were frequently continuous with the Z-bands of both control and cultured cardiac muscle cells. The transverse tubular system and gap junction were absent in newt ventricles. The functional implications of these characterisitics are discussed. At the end of 1 week of culture, the surfaces of the explants were covered by one or more layers of non-muscle cells, and the core of the explants consisted mostly of cardiac muscle cells. In a few cardiac muscle cells the myofibrillar organization was disrupted, resulting in the distribution of scattered patches of myofibrils and free myofilaments in the sarcoplasm. A small number of intact muscle cells contained a considerable number of dense granules in the sarcoplasm. At 15 days in culture, a large number of muscle cells showed structural features reminiscent of embryonic cardiac muscle cells. These cells possessed patches of myofibrils, scattered myofilaments and scanty sarcoplasmic reticulum along with other cellular organelles and inclusions. Several of these altered cardiac muscle cells contained mitotic figures. The cardiac explants maintained the initial beating rate until the end of 2 months of culture, except for the 11% of the explants which stopped beating. By 3-4 weeks in culture, most of the cardiac muscle cells possessed the altered cell morphology mentioned above. The explants after 60 days in culture became more flattened than the earlier explants. The intact cardiac muscle cells were rare, and the cores of the explants were mostly occupied by the altered cardiac muscle cells. It is evident from our studies that the cardiac muscle cells have undergone dedifferentiation in long-term culture, and that this dedifferentiation process has yet had no effect in the maintenance of contractility of the explants. Furthermore, these dedifferentiated cardiac muscle cells are capable of DNA synthesis and mitosis.
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McClellan GB, Winegrad S. The regulation of the calcium sensitivity of the contractile system in mammalian cardiac muscle. J Gen Physiol 1978; 72:737-64. [PMID: 215701 PMCID: PMC2228493 DOI: 10.1085/jgp.72.6.737] [Citation(s) in RCA: 115] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Treatment of rat ventricular cells with 10 mM EGTA makes the sarcolemma highly permeable to small ions and molecules without removing its restriction of the diffusion of larger molecules or inactivating all of its enzymatic functions. These hyperpermeable cardiac cells have been used to study the regulation of the range of concentration of Ca over which activation of the contractile proteins occurs (Ca sensitivity). The Ca sensitivity can varied from three- to sixfold without any significant alteration in the general shape of the relation between force and Ca concentrations. Although cyclic nucleotides in concentrations of 10(-9) to 10(-5) M do not influence Ca sensitivity, in the presence of a phosphodiesterase inhibitor, cGMP increases and cAMP decreases Ca sensitivity. Treatment of the hyperpermeable cells with a nonionic detergent raises Ca sensitivity as does removal of the phosphate donor by complete substitution of CTP for ATP. These data indicate that Ca sensitivity is probably modulated by a cAMP-dependent phosphorylation that decreases Ca sensitivity. The sarcolemma is required for this reaction to take place. The effect of this reaction is antagonized by a cGMP-dependent reaction occurring inside the cell. Studies involving the perfusion of the heart with and without epinephrine before the exposure to EGTA indicate that epinephrine can regulate this system of control of Ca sensitivity. The functional considerations of this regulatory system are discussed.
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Tanaka K, Smith CA. Structure of the chicken's inner ear: SEM and TEM study. THE AMERICAN JOURNAL OF ANATOMY 1978; 153:251-71. [PMID: 707316 DOI: 10.1002/aja.1001530206] [Citation(s) in RCA: 194] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
The inner ears of 35 adult chickens were studied by TEM, SEM and light microscopy. Two well differentiated hair cell/nerve ending units were present: tall hair cells with small vesiculated nerve endings were located on the attached part of the basilar membrane; short hair cells with large vesiculated nerve endings were located on the free basilar membrane except for the distal tip. In this respect the chicken ear is similar to that of the pigeon. The chickens examined did have some unique features. Sensory cells of lenticular and hemispheric shape were also present at the proximal end. Bundles of long dense tubules were seen frequently within the sensory cell cytoplasm. Kinocilia were absent from the hair bundles of many of the sensory cells. The internal structure of the kinocilia which were present was atypical and consisted of a variable number of doublets. Eight peripheral plus one central doublet were found most frequently.
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Abstract
1. The passive and active electrical parameters of frog ventricular myocardium have been measured. 2. The cytoplasmic resistivity has been determined by following changes in the resistance of a micro-electrode on penetration of a cell. 3. Unidimensional cable analysis using direct and alternating currents revealed the presence of a single time constant attributed to the surface membrane. 4. Longitudinal impedance measurements indicate that a second time constant is present in the intracellular pathway. 5. The results indicate that the resistance between cells is low so that action potentials can propagate from cell to cell by local circuits. 6. A three-dimensional cable analysis has also been carried out and compared to a simplified mathematical model which is presented in an Appendix and which closely approximates the experimental situation.
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Bass BG, Ciulla EM, Klop P, Van Baal S. Some electrical and mechanical effects of strontium on toad ventricular muscle: comparison to calcium. J Physiol 1975; 252:547-64. [PMID: 812985 PMCID: PMC1348483 DOI: 10.1113/jphysiol.1975.sp011158] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
1. The mechanical and electrophysiological effects of Sr were evaluated and compared to those of Ca in isolated, electrically driven toad ventricular muscle strips. The effects of Ca and Sr were compared at concentrations from control (2 mM) to 10 mM either by substitution of Sr for Ca at equimolar concentration, or by maintenance of a constant total Ca plus Sr concentration within which individual Ca and Sr concentrations were varied. 2. Changes in the degree of contractile activation were evaluated in terms of changes in maximal dT/dt of isometric contractions, maximal dL/dt of very lightly loaded isotonic contractions, and the shape of after-loaded force-velocity curves, with specific attention directed to the shape of the curves as they approached Vmax on the velocity axis. Effects on the cell membrane were evaluated in terms of changes in the transmembrane action potential (recorded with glass micro-electrodes) and in the mechanical parameters directly related to its duration in amphibian ventricle, viz. the duration of isometric tension and of isotonic shortening. Isometric tension and action potentials were recorded simultaneously. 3. Ca and Sr, at concentrations above control, had similar but not identical effects on dT/dt and dL/dt. Both ions alone in equimolar concentrations, or together at constant total Ca plus Sr concentration, increased dT/dt and dL/dt and shifted force-velocity curves upward. At constant total Ca plus Sr concentration, force-velocity curves were virtually superimposable as they approached the velocity intercept. 4. The duration of the action potential was markedly prolonged by Sr and shortened by Ca in concentrations above control. Unlike dT/dt and dL/dt, the total duration of isometric tension and isotonic shortening depended upon the specific Ca and Sr concentrations within a constant total concentration, and were progressively prolonged as the Sr concentration was increased. 5. The similar effects of Ca and Sr on dT/dt, dL/dt, and on the force-velocity relationship at light loads depended upon the presence of Ca ions. In Sr alone, dT/dt and dL/dt were faster than in an equimolar concentration of Ca, and time to maximal dT/dt and dL/dt was prolonged. The force-velocity curve in Sr alone was consistently shifted upward beyond the other curves in which Ca was present. These differences between the two ions are attributed in part to the rapid and early repolarization of the action potential in elevated Ca and the resultant abbreviation of the build up in active state and slower dT/dt and dL/dt. 6. The results suggest that Ca and Sr act in a similar although not identical way in activating contraction but are competitive at the cell membrane.
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Lemanski LF, Fitts EP, Marx BS. Fine structure of the heart in the Japanese Medaka, Oryzias latipes. JOURNAL OF ULTRASTRUCTURE RESEARCH 1975; 53:37-65. [PMID: 171438 DOI: 10.1016/s0022-5320(75)80085-2] [Citation(s) in RCA: 39] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Abstract
A drug-induced change in the fine morphology of the plasma membrane of heart muscle cells is described. Thus, in rabbits the chronic administration of oxyfedrine caused a marked proliferation of the plasma membrane. At the same time the mitochondria became swollen and vacuolated, and there was evidence of lysis of myofibrils. These changes are not accounted for in terms of the release of endogenous stores of catecholamines.
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Scordilis SP, Tedeschi H, Edwards C. Donnan potential of rabbit skeletal muscle myofibrils I: electrofluorochromometric detection of potential. Proc Natl Acad Sci U S A 1975; 72:1325-9. [PMID: 1055408 PMCID: PMC432526 DOI: 10.1073/pnas.72.4.1325] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The fluorescence of the dye CC-6 [(3-hexyl-2-(3-hexyl-2-benzoxazolinylidene)-1-propenyl)-benzoxazolium iodide] has been shown to indicate Donnan potentials in rabbit skeletal muscle myofibrils. These results are in agreement with previously published work in which the potentials were measured with microelectrodes on glycerol-extraced muscle fibers. The magnitude of the Donnan potential of the myofibrils has been shown to be dependent on the state (rigor or relaxed) of the system.
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Penefsky ZJ. Studies on mechanism of inhibition of cardiac muscle contractile tension by ryanodine. Mechanical response. Pflugers Arch 1974; 347:173-84. [PMID: 4207934 DOI: 10.1007/bf00592595] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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Penefsky ZJ. Ultrastructural studies of the site of action of ryanodine on heart muscle. Pflugers Arch 1974; 347:185-98. [PMID: 4857070 DOI: 10.1007/bf00592596] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Abbott RH, Leech AR. Persistence of adenylate kinase and other enzymes in glycerol extracted muscle. Pflugers Arch 1973; 344:233-43. [PMID: 4359207 DOI: 10.1007/bf00588463] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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Rumyantsev PP. Post-injury DNA synthesis, mitosis and ultrastructural reorganization of adult frog cardiac myocytes. An electron microscopic-autoradiographic study. ZEITSCHRIFT FUR ZELLFORSCHUNG UND MIKROSKOPISCHE ANATOMIE (VIENNA, AUSTRIA : 1948) 1973; 139:431-50. [PMID: 4541034 DOI: 10.1007/bf00306596] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Cantin M, Veilleux R, Huet M. Electron and fluorescence microscopy of the hamster atrium after administration of 6-hydroxydopamine. EXPERIENTIA 1973; 29:582-4. [PMID: 4738230 DOI: 10.1007/bf01926678] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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Lemanski LF. Heart development in the Mexican salamander, Ambystoma Mexicanum. II. Ultrastructure. THE AMERICAN JOURNAL OF ANATOMY 1973; 136:487-525. [PMID: 4692975 DOI: 10.1002/aja.1001360408] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Martínez-Palomo A, Mendez R. Presence of gap junctions between cardiac cells in the heart of nonmammalian species. JOURNAL OF ULTRASTRUCTURE RESEARCH 1971; 37:592-600. [PMID: 4109358 DOI: 10.1016/s0022-5320(71)80027-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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Schipp R, Beyerle-v. Wehren A. Zur funktionellen Bedeutung der osmiophilen Granula in Herzorganen niederer Vertebraten. Cell Tissue Res 1970. [DOI: 10.1007/bf00335297] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Schipp R, Flindt R. [Fine structure and innervation of the musculature of lymph hearts in amphibia (Rana temporaria)]. ZEITSCHRIFT FUR ANATOMIE UND ENTWICKLUNGSGESCHICHTE 1968; 127:232-53. [PMID: 5710350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Staley NA, Benson ES. The ultrastructure of frog ventricular cardiac muscle and its relationship to mechanism of excitation-contraction coupling. J Biophys Biochem Cytol 1968; 38:99-114. [PMID: 5691981 PMCID: PMC2107467 DOI: 10.1083/jcb.38.1.99] [Citation(s) in RCA: 155] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Frog ventricular cardiac muscle has structural features which set it apart from frog and mammalian skeletal muscle and mammalian cardiac muscle. In describing these differences, our attention focused chiefly on the distribution of cellular membranes. Abundant inter cellular clefts, the absence of tranverse tubules, and the paucity of sarcotubules, together with exceedingly small cell diameters (less than 5 micro), support the suggestion that the mechanism of excitation-contraction coupling differs in these muscle cells from that now thought to be characteristic of striated muscle such as skeletal muscle and mammalian cardiac muscle. These structural dissimilarities also imply that the mechanism of relaxation in frog ventricular muscle differs from that considered typical of other striated muscles. Additional ultrastructural features of frog ventricular heart muscle include spherical electron-opaque bodies on thin filaments, inconstantly present, forming a rank across the I band about 150 mmicro from the Z line, and membrane-bounded dense granules resembling neurosecretory granules. The functional significance of these features is not yet clear.
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Yamauchi A, Burnstock G. An electron microscopic study on the innervation of the trout heart. J Comp Neurol 1968; 132:567-88. [PMID: 5666495 DOI: 10.1002/cne.901320406] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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Zur Feinstruktur und Innervation der Lymphherzmuskulatur der Amphibien (Rana temporaria). ACTA ACUST UNITED AC 1968. [DOI: 10.1007/bf00526131] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Lee KS, Ladinsky H, Choi SJ, Kasuya Y. Studies on the in vitro interaction of electrical stimulation and Ca++ movement in sarcoplasmic reticulum. J Gen Physiol 1966; 49:689-715. [PMID: 5943610 PMCID: PMC2195502 DOI: 10.1085/jgp.49.4.689] [Citation(s) in RCA: 43] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Sarcoplasmic reticulum fragments (S.R.F.) were isolated from skeletal and heart muscles. These fragments were found to take up Ca(++) very actively from media. When monophasic square waves were passed through the S.R.F. suspension, the Ca(++) uptake by S.R.F. was decreased. When the suspension was stimulated electrically after the Ca(++) was taken up by S.R.F., the initiation and the cessation of the stimulation were followed by the release and re-uptake of Ca(++) by S.R.F., respectively. The degree of inhibition of the Ca(++) uptake as well as of the Ca(++) release by electrical stimulation was dependent on the voltage and the frequency of stimulation. The presence of inorganic phosphate or oxalate modified the influence of electrical stimulation on the release and the uptake of Ca(++) by S.R.F. Attempts were made to observe the release of Ca(++) by electrical stimulation from unfractionated sarcoplasmic reticulum remaining in myofibers, and the interaction of the released Ca(++) with myofibrils in vitro. For this purpose, the glycerol-extracted fiber was selected as a muscle model, since it contains both sarcoplasmic reticulum and myofibrils. It was found that electrical stimulation of skeletal and heart glycerol-extracted fibers resulted in the contraction of fibers. It appeared that the contraction of glycerol fibers by electrical stimulation was caused by the Ca(++) release from sarcoplasmic reticulum by stimulation.
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Smith DS. The organization and function of the sarcoplasmic reticulum and T-system of muscle cells. PROGRESS IN BIOPHYSICS AND MOLECULAR BIOLOGY 1966; 16:107-42. [PMID: 5338779 DOI: 10.1016/0079-6107(66)90004-6] [Citation(s) in RCA: 129] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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