Muscular hypertrophy

Anabolic steroids decrease catabolism and increase skeletal muscle protein synthesis. Whether this results in muscular hypertrophy or hyperplasia, or a combination of these, is unclear and probably depends upon the muscle studied. Different muscle types contain different cytosolic receptor numbers and, therefore, the response to anabolic steroids varies. Anabolic steroids initiate an increase in RNA polymerase activity and the synthesis of either structural or contractile proteins. In some muscles, anabolic steroids may increase the ratio of fast twitch to slow twitch fibers (Nimmo et al 1982, Snow et al 1982). Increased activity of enzymes involved in energy metabolism may also occur. However, the total glycogen content may remain unchanged (Hyyppa et al 1997). The effects are most profound in females and castrated males (Snow 1993). 

HYPERPLASIA An increase in the number of cells. The majority of muscle bulk that comes from using anabolic steroids occurs from muscular hypertrophy. Some studies suggest that anabolic steroids can possibly cause hyperplasia or an increase in the actual number of muscle cells. Many feel that Growth Hormone causes hyperplasia which enables more muscular development than using anabolic steroids alone. This theory is controversial. 

Pelvic veins are uniquely predisposed to become dilated, even without pregnancy. Many pelvic veins are devoid of valves and have weak attachments between the adventitia and supporting connective tissue [12]. Although this is different from veins elsewhere in the body the histology of pelvic varicosities is similar to that of varicose veins elsewhere, including fibrosis of the tunica intima and media, muscular hypertrophy and proliferation of capillary endothelium. 

Fig. 16.2. Salpingitis isthmica nodosa Multiple tiny diverticula in the right isthmic portion (arrows) caused by mucosal proliferation and muscular hypertrophy with mucosal invasion into the muscularis partial tubectomy on the left side (arrow head)...

In general, 3D endoscopic views can provide improved visualization of these morphological features. One exception would be the visualization of the highly characteristic stalk of a pendunculated lesion in a segment with marked muscular hypertrophy of diverticulosis. In this setting, 2D MPR may offer an advantage, due to the impaired endoscopic visualization within the thickened folds (Fig. 7.6). 

Fig.7.6a,b. Pedunculated lesion in area of luminal narrowing and marked diverticulosis a axial 2D MPR view best visualizes the characteristic stalk (arrows) from the polyp head (arrowhead), compared to b b 3D volume rendered view, with polyp head shown (arrowheads), but stalk obscured by luminal narrowing and muscular hypertrophy... 

Elbadawi, A. (1983) Autonomic muscular innervation of the vesical outlet and its role in micturition. In F.J., Hinman, ed. Benign Prostatic Hypertrophy New York Springer-Verlag, pp. 330-348. 

These experimental models indicate that muscle hypertrophy occurs through increases in protein synthesis and suggest that weightlifting should require increased dietary protein. The confusion is derived from the interpretation of the quantity of protein needed to meet this increased need. The RDA s state that "there is little evidence that muscular activity increases the need for protein, except by the small amount required for the development of muscles during conditioning." The amount has been... 

Hypertrophy Milk leg after childbirth Muscular weakness Nervous exhaustion Obesity Skin eruptions Sleepiness Sluggishness... 

Cyclobenzaprine (10 mg t.i.d.) is a centrally acting skeletal muscle relaxant and is indicated as an adjunct to rest and physical therapy for relief of muscular spasm associated with injury related to painful musculoskeletal conditions. However, cyclobenzaprine is not effective in spasticity associated with cerebral or spinal cord injury. Cyclobenzaprine is structurally related to tricyclic antidepressants possessing sedative and anticholinergic properties. Therefore, cyclobenzaprine should be used cautiously in individuals with angle-closure glaucoma and urinary retention due to obstruction or prostatic hypertrophy. Because it causes drowsiness and blurred vision, it should be used carefully when alermess is required. 

Hypertension is usually a temporary adjustment to emotional stress or trauma, but after sustained hypertension, the condition perpetuates itself, becoming essential hypertension. The left ventricle of the heart, challenged by the need to pump blood against pressure higher than normal, develops a thickened muscular wall, called cardiac hypertrophy. The extra muscular mass requires additional oxygen, and any decrease in coronary blood flow has more serious consequences in hypertensive patients than in normal individuals. Myocardial infarction (muscle cells die due to lack of oxygen) is therefore more of a threat in hypertensive patients than in normals. Even with the implantation of a replacement heart, the underlying causes of the heart failure have not been eliminated, and the cycle is likely to repeat. 

Muscular degeneration and mild hyalinization of the muscles have also been described. In addition to the alteration described in the nervous system and muscles, changes in the endocrine glands frequently observed in experimental thiamine deficiency include hypertrophy of the thyroid, anterior hypophysis, adrenal, and islet of the pancreas. 

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