169,993 research outputs found
Effects of clenbuterol on rabbit growth, nitrogen balance and skeletal muscle fibres
No full text27 male N.Z.W. rabbits (1953 +/- 32 g initial live weight) were housed in individual metabolic cages in a controlled environment maintainedat a temperature of 18-degrees-C, illuminated between 8 AM and 8 PM. The animals were divided into 3 homogenous groups fed ad libitum (from6 PM to 9 AM) diets containing different levels of clenbuterol (CB) (C: control diet, T-0.5: control diet plus 0.5 mg/kg CB, T-1: control diet plus 1 mg/kg CB). Two N-balance trials were performed:days 4 through 8 and days 27 through 31 from the beginning of administration of experimental diet. CB treatment significantly improved final live weight (about + 8.9%), with no dose-effect. Treatment did not affect feed intake, while a better feed efficiency was observed for groups receiving CB. During the N-balance study no treatment-effects wereobserved on N intake nor on fecal N. The beta-adrenergic agonist increased N-retained (P < 0.01) and reduced N-urinary excretion (P < 0.01). The effects of CB treatment on reducing urea, OH-proline and alpha-amino-N excretion were initially greater. Our data indicate that the beta-agonist reduces amino acid oxidation, collagen protein degradation and spares amino acids, thus contributing to enhanced efficiency of N deposition. Creatinine-N excretion was significantly increased only during second period of N-balance (P < 0.001). Treatment with CB significantly improved the dressing percentage. The semimembranosus muscle was significantly heavier in the treated group (T-1) than in the controls, due to muscle hypertrophy. The muscle hypertrophy caused by CB included a general effect on the cross-sectional area of all fibre types and a transformation of fibre types, especially type IIA to IIB
Neurotransmitters, neuromodulators, and neurotrophin receptors in the gut of pantex, a hybrid sparid fish (Pagrus major x Dentex dentex). Localizations in the enteric nervous and endocrine systems
No full textThe gut of Pantex, a sparid hybrid fish (Pagrus major x Dentex dentex) with a great potential importance for the Italian aquaculture, was histochemically and immunohistochemically investigated in order to evidence components of the intramural nervous and diffuse endocrine systems. The general structural aspects of the intramural nervous system were shown by the Nissl-thionin staining. As in most other fish, it was only organized in the myenteric plexus. Acetylcholinesterase (AChE) activity was observed in both nerve cell bodies and terminals all along the gut. The NADPH-diaphorase reactivity too, possibly linked to the synthesis and release of nitric oxide, was present in nerve cell bodies and nerve terminals of the oesophagus, stomach and intestine. In addition, the intramural nervous system was shown to contain Trk (tyrosinekinase) receptors for neurotrophin, as evidenced by Trk A-, Trk B- and Trk C-like immunoreactivities, thus suggesting an involvement of neurotrophin in the function of this system. Trk B- and Trk C-like immunoreactivities were detected in epithelial endocrine cells, too. The additional presence of serotonin- and metenkephalin-like immunoreactivities in numerous endocrine cells in the epithelial layers of the stomach and intestine was showed
In vitro propagation of Primula allionii Loisel.
No full textAbstract Primula allionii is a protected small herbaceous perennial plant that is endemic to the French and Italian Maritime Alps and has an interesting ornamental value. The aim of this work was to establish a clonal propagation protocol for commercial exploitation and for ex situ conservation of its natural genepool. Owing to the poor germination potentiality a micropropagation protocol was established for three seedling clones (A,B,C); the treatment with BA (0.3 mg l-1) induced a significant response in all clones respect to the other treatments and reached in clone C a multiplication rate of 3. BA gave also a dissimilar leaf shape. Furthermore, the variability in the plant behaviour is related to the genotype. Rooting was achieved for clones B and C with a general average of 57%; the best result (69%) was obtained in the presence of 30 g l-1. Plants of the two clones coming from rooting media showed 43% (clone B) and 74% (clone C) of acclimatization; the addition of activated charcoal permitted to increase the behaviour of plants of clone B that reached in this case 68% acclimatization
Expression of myosin heavy chain isoforms in laryngeal muscles in comparison with skeletal and special muscles
No full textLarynx in mammals is characterized by five intrinsic laryngeal muscles with complex movements involved in respiration, airway protection and phonation. These muscles, differently from limb and trunk muscles that derived from somites, originate from the branchial arches. In all species the laryngeal muscles have the capacity to express the transitional embryonic and perinatal isoforms in adult but at low level ([1-4]). In same species of mammals (horse and cow) the laryngeal muscles express only the three skeletal MyHC isoforms (type 1, 2A and 2X) ([3], [5]); other species (dog, cat and tiger) express also a faster isoform, not detectable in skeletal muscles, the 2B isoform [4,6,7]. Furthermore, in species where the 2B isoform is present in skeletal muscles (rat and rabbit), another isoform presumably faster is present, the EO MyHC ([8], [9]). In rat and human laryngeal muscles a different isoform (IIL MyHC) was described [10,11], but it is unclear if this new isoform correspond to EO in rat or to 2B in human or to the two novel isoforms identified by Rossi et al. [12] in EO muscles (codified by MYH 14 and 15 genes). Combining RNA expression, electrophoresis and immunoblot we demonstrated that the IIL isoform in human does not correspond to type 2 isoforms (2A, 2X, 2B, EO, embryonic and perinatal cluster), to cardiac isoforms (beta and alfa), to M isoform and to isoforms codified by MYH 14 and 15 gene, and therefore is probably a new isoform.
[1] Jung HH, Han SH, Choi JO. Expression of myosin heavy chain mRNA in rat laryngeal muscles. Acta Otolaryngol. 1999; 119(3):396-402.
[2] Malmgren LT, Lovice DB, Kaufman MR. Age-related changes in muscle fiber regeneration in the human thyroarytenoid muscle. Arch Otolaryngol Head Neck Surg. 2000; 126(7):851-6.
[3] Toniolo L, Maccatrozzo L, Patruno M, Caliaro F, Mascarello F, Reggiani C. Expression of eight distinct MHC isoforms in bovine striated muscles: evidence for MHC-2B presence only in extraocular muscles. J Exp Biol. 2005; 208:4243-53.
[4] Toniolo L, Maccatrozzo L, Patruno M, Pavan E, Caliaro F, Rossi R, Rinaldi C, Canepari M, Reggiani C, Mascarello F. Fiber types in canine muscles: myosin isoform expression and functional characterization. Am J Physiol Cell Physiol. 2007; 292(5):C1915-26.
[5] Rhee HS, Steel CM, Derksen FJ, Robinson NE, Hoh JF. Immunohistochemical analysis of laryngeal muscles in normal horses and horses with subclinical recurrent laryngeal neuropathy. J Histochem Cytochem. 2009; 57(8):787-800.
[6] Wu YZ, Baker MJ, Crumley RL, Blanks RH, Caiozzo VJ. A new concept in laryngeal muscle: multiple myosin isoform types in single muscle fibers of the lateral cricoarytenoid. Otolaryngol Head Neck Surg. 1998; 118(1):86-94.
[7] Bergrin M, Bicer S, Lucas CA, Reiser PJ. Three-dimensional compartmentalization of myosin heavy chain and myosin light chain isoforms in dog thyroarytenoid muscle. Am J Physiol Cell Physiol. 2006; 290(5):C1446-58.
[8] Lucas CA, Rughani A, Hoh JF. Expression of extraocular myosin heavy chain in rabbit laryngeal muscle. J Muscle Res Cell Motil. 1995; 16(4):368-78.
[9] Briggs MM, Schachat F. Early specialization of the superfast myosin in extraocular and laryngeal muscles. J Exp Biol. 2000; 203:2485-94.
[10] DelGaudio JM, Sciote JJ, Carroll WR, Escalmado RM. Atypical myosin heavy chain in rat laryngeal muscle. Ann Otol Rhinol Laryngol. 1995; 104(3):237-45.
[11] Toniolo L, Macchi V, Porzionato A, Paoli A, Marchese-Ragona R, De Caro R, Reggiani C. Myosin heavy chain isoforms in human laryngeal muscles: an expression study based on gel electrophoresis. Int J Mol Med. 2008; 22(3):375-9.
[12] Rossi AC, Mammucari C, Argentini C, Reggiani C, Schiaffino S. Two novel/ancient myosins in mammalian skeletal muscles: MYH14/7b and MYH15 are expressed in extraocular muscles and muscle spindles. J Physiol. 2010; 588:353-64
Pseudomyotonia in Romagnola cattle caused by novel ATP2A1 mutations
No full textBackground
Bovine congenital pseudomyotonia (PMT) is an impairment of muscle relaxation induced by exercise preventing animals from performing rapid movements. Forms of recessively inherited PMT have been described in different cattle breeds caused by two independent mutations in ATP2A1 encoding a skeletal-muscle Ca2+-ATPase (SERCA1). We observed symptoms of congenital PMT in four related Romagnola beef cattle from Italy and evaluated SERCA1 activity and scanned ATP2A1 for possible causative mutations.
Results
We obtained four PMT affected Romagnola cattle and noted striking clinical similarities to the previously described PMT cases in other cattle breeds. The affected animals had a reduced SERCA1 activity in the sarcoplasmic reticulum. A single affected animal was homozygous for a novel complex variant in ATP2A1 exon 8 (c.[632 G>T; 857 G>T]). Three out of four cases were compound heterozygous for the newly identified exon 8 variant and the exon 6 variant c.491 G>A(p. Arg146Gly), which has previously been shown to cause PMT in Chianina cattle. Pedigree analysis showed that the exon 8 double mutation event
dates back to at least 1978. Both nucleotide substitutions are predicted to alter the SERCA1 amino acid sequence (p.[(Gly211Val; Gly284Val)]), affect highly conserved residues, in
particular the actuator domain of SERCA1.
Conclusion
Clinical, biochemical and DNA analyses confirmed the initial hypothesis. We provide functional and genetic evidence that one novel and one previously described ATP2A1 mutation lead to a reduced SERCA1 activity in skeletal muscles and pseudomyotonia in affected Romagnola cattle. Selection against these mutations can now be used to eliminate the mutant alleles from the Romagnola breed
Different putative neuromodulators are present in the nerves which distribute to the teleost skeletal muscle.
No full textThe presence of putative neuromodulators in the nerve fibres was investigated in white skeletal muscle of two teleost fish not taxonomically correlated and showing different patterns of innervation (multiple versus focal innervation). Cryostat sections of epaxial, hypaxial and adductor mandibulae (AM) muscles of Sparus aurata and Anguilla anguilla were stained histochemically for reduced nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase. Other sections were used for indirect immunohistochemistry (streptavidin-biotin and rhodamine immunofluorescence methods), employing antibodies specific for putative excitatory or inhibitory peptides, including CGRP, substance P, met-enkephalin, bombesin, and VIP. In addition, ultrastructural observations were performed in order to describe the morphology of the motor endplates. A strong immunoreactivity for CGRP and substance P was found in many nerve terminals. Met-enkephalin, bombesin and VIP immunoreactivities were less frequently observed. No immunoreactivity was observed to CCK, NPY or 5-HT. NADPH-diaphorase was identified in nerve fibres of the AM complex only of A. anguilla. Electron microscopy observations evidenced more than one type of synaptic vesicle in motor endplates. Some differences in putative neuromodulator distributions were observed in the two species and muscle complexes, which may be related to the different taxonomical position as well as the different pattern of innervation of white muscle fibres
Ultrastructural features of the gut in the white sturgeon, Acipenser transmontanus
No full textElectron-microscopic examinations of the sturgeon gut were performed. Oesophageal goblet cells were abundant in the stratified epithelium. The ultrastructural features of the secretory granules of the oesophageal and intestinal goblet cells were quite similar to those of other vertebrates. Lobules of multilocular adipose tissue were observed in the deep tunica propriasubmucosa of the oesophagus, in close association with vasculature and large fibre bundles of myelinated and unmyelinated axons. Similarly composed nerve fibre bundles were observed in the cardiac stomach, too. The presence of myelinated axons is an unusual feature in the vertebrate enteric nervous system. Cardiac and fundic zones of the stomach showed an epithelium with columnar ciliated and non-ciliated cells, the latter equipped with fuzzy microvilli. Cells lining the tubular gastric proper glands were markedly granulated. Intestinal superficial epithelium was columnar and contained ciliated, as well as non-ciliated and goblet cells. In the tunica propria all over the intestine, the presence and ultrastructure of granulated cells was in addition described. Intraepithelial granulated leukocytes were seen throughout the alimentary canal. Various types of endocrine cells were seen both in the stomach and in the intestine, the size of their granules was measured and their ultrastructure described and compared to that of mammalian cell types
Ultrastructural features of the gut in the white sturgeon, Acipenser transmontanus.
No full textElectron-microscopic examinations of the sturgeon gut were performed. Oesophageal goblet cells were abundant in the stratified epithelium. The ultrastructural features of the secretory granules of the oesophageal and intestinal goblet cells were quite similar to those of other vertebrates. Lobules of multilocular adipose tissue were observed in the deep tunica propriasubmucosa of the oesophagus, in close association with vasculature and large fibre bundles of myelinated and unmyelinated axons. Similarly composed nerve fibre bundles were observed in the cardiac stomach, too. The presence of myelinated axons is an unusual feature in the vertebrate enteric nervous system. Cardiac and fundic zones of the stomach showed an epithelium with columnar ciliated and non-ciliated cells, the latter equipped with fuzzy microvilli. Cells lining the tubular gastric proper glands were markedly granulated. Intestinal superficial epithelium was columnar and contained ciliated, as well as non-ciliated and goblet cells. In the tunica propria all over the intestine, the presence and ultrastructure of granulated cells was in addition described. Intraepithelial granulated leukocytes were seen throughout the alimentary canal. Various types of endocrine cells were seen both in the stomach and in the intestine, the size of their granules was measured and their ultrastructure described and compared to that of mammalian cell types
A morphological, histochemical and immunohistochemical analysis of the neuroendocrine system of the gut in the pantx, a hybrid sparid fish (Pagrus major X Dentex dentex)
No full textHistochemical and immunohistochemical investigation of muscle fibres in the sturgeon (Chondrostei; Acipenser)
No full textThe arrangement and innervation of lateral muscle and adductor mandibulae (AM) complex were examined histochemically and immunohistochemically in the stuqgebn Acipenser transmontanus. Lateral muscle was arranged) in myotomes in which the superficial slow-red muscle layer and the deep fastwhite muscle layer were separated by an intermediate layer of pink muscle. The AM complex was composed of a small slowred muscle layer, but the bulk of the muscle was composed of fast-white fibres. Pink fibres appeared both in an intermediate layer and scattered throughout the fast-white muscle. The innervation appeared to resemble that of elasmobranchs and some teleosts. Slow-red fibres of lateral muscle were multiply innervated, whereas fast-white muscle fibres were focally innervated at the myoseptal end. Pink fibres of lateral muscle and fast-white fibres of AM were focally innervated in the mid-region
of the fibres. There were no significant differences between 5 month old and adult sturgeons except for a much better developed intermediate (pink) layer surrounding the lateral line in the adult
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