Plasma lipids factors affecting

Aside from the first-dose phenomenon, the reported toxicities of the a blockers are relatively infrequent and mild. These include dizziness, palpitations, headache, and lassitude. Some patients develop a positive test for antinuclear factor in serum while on prazosin therapy, but this has not been associated with rheumatic symptoms. The blockers do not adversely and may even beneficially affect plasma lipid profiles, but this action has not been shown to confer any benefit on clinical outcomes. 

Factors Affecting Plasma Lipids and Lipoproteins with Exercise... 

Even though the mortality from coronary heart disease has declined recently, atherosclerosis and related vascular disorders still are the leading cause of death in the Western world. The etiology of this disease is multifactorial, with hyperlipidemia, smoking, diabetes mellitus, hypertension, and obesity being well-established risk factors for the development of atherosclerosis. Dietary fat affects plasma lipids, lipoproteins, and vascular inflammation and, thus, is linked to atherosclerosis. 

Lipid transport mechanisms exist that shuttle cholesterol and triglycerides among the liver, intestine, and other tissues. Normally, plasma lipids, including lipoprotein cholesterol, are cycled into and out of plasma and do not cause extensive accumulation of dcpo.sits in the walls of arteries. Genetic factors and changes in hormone levels affect lipid transport by altering enzyme concentrations and apoprotein content, as well us the number and activity of lipoprotein receptors. This complex relationship makes the treatment of all hyperlipoproteinemias by a singular approach difficult, if not impractical. 

Although current recommended National Cholesterol Education Program/American Heart Association Step 1 or Step II diets have beneficial effects in lowering total and LDL cholesterol concentrations [190], they tend to decrease HDL cholesterol and increase TAG concentrations, thereby potentially adversely affecting coronary risk factors [191,192]. It is, therefore, imperative to identify alternative diets that can effectively modify the plasma lipid profiles and thus reduce CHD risk. 

In trying to assess the pathological significance of the foregoing effects of oral contraceptives upon plasma lipids, it should be borne in mind that TG levels are markedly affected by such factors as dietary intake, age, obesity, preclinical diabetes and race. 

Factors Affecting Stability to Heat Plasma and serum are notable for their capacity to hold in stable aqueous solution many substances whose solubility in pure water or salt solutions is extremely low. The remarkable capacity of certain globulin fractions— notably those from Fractions III-O and IV-1, as separated by the low temperature-ethanol technique— to bind cholesterol, phos-phatides, and other types of lipid material, in stable, water-soluble combination has already been described in the preceding section. Serum albumin, however, displays equally remarkable afiSnities for a somewhat different and extremely diverse group of substances, including many types of acid and basic dyes, the ions of many organic acids containing hydrocarbon residues, certain quinone derivatives, and other substances. 

Cardiovascular disease is a major cause of mortality and morbidity in industrialized countries. Several risk factors have been linked to incidence of cardiovascular disease and include hypertension, lipid abnormahties (high plasma cholesterol and triacylglycerol levels), atherosclerosis, obesity, diabetes, smoking, stress, heredity, and diet. Dietary GLA affects many of these parameters and is discussed below. 

Several factors that determine antibiotic diffusion into prostatic secretions were delineated from the canine model. Lipid solubility is a major determinant in the ability of drugs to diffuse from plasma across epithelial membranes. The degree of ionization in plasma also affects the diffusion of drugs. Only un-ionized molecules can cross the lipid barrier of prostatic cells, and the drug s pKa directly determines the fraction of unchanged drug. 

The uptake of lipids across the brush border plasma membrane into the enterocyte is considered to be a transport process that requires no energy [8], The route of transfer of lipids thus has to take place via a process of passive diffusion. A theoretical model for passive lipid solute transfer that takes into account the different factors that affect the rate of transport has been worked out by Dietschy and collaborators [8,68] (cf. Chapter 5). 

The lipids in milk exist as microscopic globules in an oil-in-water (OAV) emulsion. On the interface between globules and milk plasma is a membrane that stabilizes the emulsion. Many factors can affect the milk lipid content, particularly genetics, feed, stage of lactation, and climate. Cow s milk contains approximately 2.8 to 6% total lipids, 3.5 to 4% on average. 

Since the general problem has largely become one in which the level of lipid-soluble autoxidizable material in the tissues is paramount in practical importance, more attention has been paid to the factors which affect tissue autoxidizability. In animals, as indicated above, attempts are being made to relate the rate at which polyunsaturated fatty acids accumulate in the various tissues. In man, one is practically limited to examination of the components of plasma, erythrocytes, and depot fat samples if multiple examinations of large groups are to be made. 

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