Skeletal muscle localization

African trypanosomiasis (sleeping sickness) and American trypanosomiasis (Chagas disease) are caused by Trypanosoma brucei and Trypanosoma cruzi, respectively. Sleeping sickness results from being bitten by the insect vector, the tsetse fly. At first there is only local lymphadenitis but about a month later generalized malaise, fever, and systemic disease involving skeletal muscle is seen. 

A wide selection of monoclonal and polyclonal anti-Ca -ATPase antibodies have become available in recent years. Studies with these antibodies defined the localization of Ca " -ATPase in the sarcoplasmic reticulum of developing and mature skeletal muscles [60,262-270] and established a pattern of cross reactivity with various Ca -ATPase isoenzymes in the sarco(endo)plasmic reticulum [270-286] and in the plasma membrane [284,287-290] of skeletal, cardiac and smooth muscles. Antibodies have also proved useful in the quantitation of Ca -ATPase, both in muscles of diverse fiber types [291-294] and in COS-1 cells transfected with Ca -ATPase cDNA [97,103,126,127,129,215],... 

Kayano, T., et al. Evidence for a family of human glucose transporterlike proteins. Sequence and gene localization of a protein expressed in fetal skeletal muscle and other tissues. J. Biol. Chem. 1988, 263, 15245-15248. 

FIG. 4. Model of RyR-mediated Ca2+ release in muscle. Evidence indicates allosteric coupling between the L-type Ca2+ channel and RyRl in skeletal muscle, tight coupling between the channels in cardiac (RyR2), and loose coupling to localized RyR (probably RyR2) in smooth muscle. 

Fig. 12.2 Immunogold localization of endothelial NO synthase (NOS3) in skeletal muscles, a Immunogold labeling of NOS3 in subsarcolemmal mitochondria, b Inside of the sarcoplasm NOS3 is localized along the contractile fibers, in the sarcoplasmic reticulum and in mitochondria. EPON embedding, etching with sodium ethoxide, antigen retrieval in citrate buffer, pH 6.0. 12 nm immunogold.

Devlin DJ, Mills JW, Smith RP. 1989a. Histochemical localization of rhodanese activity in rat liver and skeletal muscle. Toxicol Appl Pharmacol 97 247-255. 

An increasing number of studies on lipid metabolism in human skeletal muscle using localized MR proton spectroscopy have been performed since the first description of the phenomenon that proton NMR spectroscopy allows the differentiation of two distinct lipid compartments and the experimental confirmation that one of these compartments is attributed to the IMCL pool. The non-invasiveness and the high sensitivity even to low lipid concentrations under physiological conditions denote the uniqueness of this modality and allow examinations of large numbers of healthy volunteers and follow-up metabolic intervention studies. 

Unfortunately, paralysis of skeletal muscle attained by using curare-like compounds, in the majority of cases, is not useful for general conditions of spasticity accompanied by the CNS involvement, as well as for local injuries or inflammation. Of course, neuromuscular blockage reduces spasms however, it is accompanied by loss of voluntary movement. 

Malignant hyperthermia Amide local anesthetic administration has been associated with acute onset of fulminant hypermetabolism of skeletal muscle known as malignant hyperthermic crisis. Recognition of early unexplained signs of tachycardia. 

Muscle relaxant As an adjunct for the relief of skeletal muscle spasm because of reflex spasm caused by local pathology, spasticity caused by uppermotor neuron disorders, athetosis, stiff-man syndrome, used parenterally in the treatment of tetanus (diazepam). 

Pharmacology Cyclobenzaprine, structurally related to the tricyclic antidepressants (TCAs), relieves skeletal muscle spasm of local origin without interfering with muscle function. It is ineffective in muscle spasm caused by CNS disease. The net effect is a reduction of tonic somatic motor activity, influencing both gamma and alpha motor systems. 

An adjunct for the relief of skeletal muscle spasm caused by reflex spasm to local pathology (such as inflammation of the muscles or joints, or secondary to trauma) spasticity caused by upper motor neuron disorders athetosis stiff-man syndrome. Injectable diazepam may also be used as an adjunct in tetanus. 

Mecfianism of Action A centrally acting skeletal muscle relaxant that reduces tonic somaticmuscleactivityat the level of the brainstem. TfterflpeMtic Effect Relieves local skeletal muscle spasm. 

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