Muscles, skeletal smooth

CK Originates from cardiac muscle, skeletal smooth muscle and brain. Isoenzyme measurements used, paliculaily CK-MB in myocardial inlaiclion... 

The compliance in series with the active force. Force exerted by the activated elements must be transmitted or borne by whatever structural elements are in series with them. In skeletal muscle there is clearly a tendon in series but not so with smooth muscle. In smooth muscle, the total length of contractile apparatus is broken up into individual cells with intercalating extracellular connective structures. In addition, the portions of the crossbridges in series with the pulling site must also be stretched before force can rise to isometric levels. Taken together, the... 

CK has a dimeric structure composed of two subunits designated M and B ( )> M for muscle and B for brain, with the isoenzymes being designated MM, MB and BB. The MM dimer is found in skeletal muscle and minimally in smooth and cardiac muscle. The BB dimer is found in brain and minimally in lung and smooth muscle (42). The MB isoenzyme of intermediate electrophoretic mobility is found chiefly in myocardium (43) and very little in skeletal muscle and smooth muscle. 

Connective tissue, muscle (skeletal and smooth), heart, pancreas, brain, lung, gonads, mesentery Discontinuous endothelium Fenestrated... 

Describe the morphological differences between skeletal muscle and smooth muscle... 

Feature Skeletal muscle Multiunit smooth muscle Single unit smooth muscle... 

Contraction of smooth muscle is significantly slower than that of skeletal muscle. Furthermore, smooth muscle contraction is quite prolonged (3000 msec) compared to that in skeletal muscle (100 msec). The slow onset of contraction as well as its sustained nature is due to the slowness of attachment and detachment of the myosin crossbridges with the actin. Two factors are involved ... 

So far three subtypes of ft receptors have been identified and cloned. They differ in their distribution, the Pi type being found in the heart, the P2 in lung, smooth muscle, skeletal muscle and liver, while the P type occurs in adipose tissue. There is evidence that P2 adrenoceptors occur on the lymphocyte membrane also but the precise function there is unknown. 

The musculature is what makes movements possible. In addition to the skeletal muscles, which can be contracted voluntarily, there are also the autonomically activated heart muscle and smooth muscle, which is also involuntary. In all types of muscle, contraction is based on an interplay between the proteins actin and myosin. 

L Cayl. 1-Cavl 3 Cardiac, skeletal, smooth muscle, neurons (Cav1.4 is found in retina), endocrine cells, bone Long, large, high threshold Verapamil, DHPs, Cd2+, [Pg.259]

The actions of U-II are mediated by a G protein-coupled receptor referred to as the UT receptor. UT receptors are widely distributed in the brain, spinal cord, heart, vascular smooth muscle, skeletal muscle, and pancreas. Some effects of the peptide including vasoconstriction are mediated by the phospholipase C, IP3-DAG signal transduction pathway. 

Tissue Neurons, skeletal muscle Macrophages, smooth muscle cells Endothelial cells, neurons... 

ATP + myosin light chain <1> (smooth-muscle, skeletal muscle, <1> [1] smooth-muscle, cardiac, <1> [4] smooth-muscle, myosin, rat brain, <1>... 

There are three types of muscles smooth, cardiac, and skeletal. Smooth muscles help move food and fluids through your body. Cardiac muscles pump blood through your heart. Skeletal muscles are the kind that attach to your bones. They allow you to run, dance, lift, turn, and, in general, move through your environment. Physical fitness involves resilience in all muscle types. For this essay, however, our focus will be on the more physically apparent skeletal muscles, which can account for up to 40 percent of your total mass. 

A third tissue is muscle, which is classified into three types striated (voluntary skeletal muscle), cardiac (involuntary striated muscle), and smooth (involuntary) muscle. There are two major groups of cells in nervous tissue, the fourth tissue type. Neurons are the actual conducting cells whose cell membranes carry nerve impulses. Several kinds of glial cells lie between and around the neurons. 

There is probably no biological phenomenon that has excited more interest among biochemists than the movement caused by the contractile fibers of muscles. Unlike the motion of bacterial flagella, the movement of muscle is directly dependent on the hydrolysis of ATP as its source of energy. Several types of muscle exist within our bodies. Striated (striped) skeletal muscles act under voluntary control. Closely related are the involuntary striated heart muscles, while smooth involuntary muscles constitute a third type. Further distinctions are made between fast-twitch and slow-twitch fibers. Fast-twitch fibers have short isometric contraction times, high maximal velocities for shortening, and high rates of ATP hydrolysis. 

Beta-2 Bronchiole smooth muscle Some arterioles (skeletal muscle, liver] Gastrointestinal smooth muscle Skeletal muscle and liver cells Uterus Gallbladder Relaxation (bronchodilation] Vasodilation Decreased motility Increased cellular metabolism Relaxation Relaxation... 

Acetylcholine receptors are classified as either muscarinic cholinergic receptors or nicotinic cholinergic receptors. The alkaloid muscarine mimics the effects produced by stimulation of the parasympathetic system. These effects are postganglionic and are exerted on exocrine glands, cardiac muscle, and smooth muscle. The alkaloid nicotine mimics the actions of acetylcholine, which include stimulation of all autonomic ganglia, stimulation of the adrenal medulla, and contraction of skeletal muscle. 

Hydromorphone affects the respiratory center in the brain, and this is why it suppresses the cough reflex. Hydromorphone is partially broken down, or metabolized, by the liver and is absorbed by a variety of tissues and organs, including the gastrointestinal tract, smooth muscle, skeletal muscle, pancreas, lungs, cardiovascular system, and central nervous system. Once metabolized by the liver, hydromorphone moves out of the body by way of the kidneys and into the urine. The precise mechanisms by which hydromorphone and the other narcotic analgesics work are not entirely known. 

In vitro, urotensin II is a potent constrictor of vascular smooth muscle its activity depends on the type of blood vessel and the species from which it was obtained. Vasoconstriction occurs primarily in arterial vessels, where urotensin II can be more potent than endothelin 1, making it the most potent known vasoconstrictor. In vivo, urotensin II has complex hemodynamic effects, the most prominent being regional vasoconstriction and cardiac depression. The extent to which the peptide is involved in the regulation of vascular tone and blood pressure in humans is not clear recent studies have produced conflicting results. The actions of urotensin II are mediated by G protein-coupled receptors that are widely distributed in the brain, spinal cord, heart, vascular smooth muscle, skeletal muscle, and pancreas. Some effects of the peptide including vasoconstriction are mediated by the phospholipase C/IP3/DAG signal transduction pathway. 

An enhancement of ATPase action comes through the phosphorylation of myosin light chains (MW 18,000). The phosphorylation is achieved because the high cellular [Ca2+] activates myosin kinase, an enzyme that contains calmodulin, a Ca2+-binding subunit. Phosphorylation of myosin is absolutely required for smooth muscle contraction, though not for the contraction of skeletal or cardiac muscle, because smooth muscle has no troponin. Thus, whereas contraction and relaxation in skeletal and cardiac muscle are achieved principally via the action of Ca2+ on troponin, in smooth muscle they must depend solely on the Ca2+-dependent phosphorylation of myosin. In skeletal and cardiac muscle, once the stimulus to the sarcolemma is removed, [Ca2+] in sarcoplasm drops rapidly back to 10 7 or 10 8 M via various Ca2+ pump mechanisms present in the sarcoplasmic reticulum, and tropomyosin can once again interfere with the myosin-actin interaction. 

Smooth muscle differs from skeletal and cardiac muscle in its energy utilization as well. Smooth muscles are not as dependent on oxygen availability as cardiac and skeletal muscles are. Smooth muscle uses glycolysis to generate much of its metabolic energy. 

SLE systemic lupus erythrematosus. smooth muscle (involuntary muscle plain muscle) Unlike striated muscle, smooth muscle has no cross-striations under the microscope, indicating an organization characteristic of muscle controlled by the autonomic nervous system, and reacts more slowly to neurotransmitters than striated muscle (skeletal muscle) of the voluntary nervous system. 

Other Tissues. Sulphonylurea receptors have also been described for cardiac muscle, skeletal muscle and smooth muscle but do not appear to be of therapeutic benefit for lowering blood sugar (Panten et al., 1992). Specific binding to membranes isolated from other rat tissues (liver, lung, kidney, heart, spleen, diaphragm, duodenum, colon and stomach) was... 

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