Serum alkaline phosphatase subjects

In Table 10 (Parts I and II) are listed the data on the partition of serum alkaline phosphatase for 33 normal subjects according to blood type and status of the slow intestinal band. A statistical analysis appears in Table 11. 

Statistical Comparison op Mean Values of Different Moieties of Serum Alkaline Phosphatase in Blood Group A and B Subjects... 

Views on the Nature op Serum Alkaline Phosphatase in Normal Adult Subjects... 

In the pregnant subject, the placenta and intestine become the two major sources of serum alkaline phosphatase. Like intestine, placenta is a rich source of alkaline phosphatase and it enriches the outermost cell membranes of the microvilli of the syncytiotrophoblast, which is bathed by the maternal circulation. The properties of the placental enzyme differ sufficiently from those of the intestinal isozyme to permit their differentiation. ... 

The biochemical fractions of the serum alkaline phosphatase in cirrhosis are listed in Table 13 according to blood types A and 0. It may be advantageous to compare the various moieties in these patients with the data on normal subjects of corresponding blood type (Table 10). In some cases (4, 5, 14) the elevation is proportionate in the LPSAP and non-LPSAP moieties, whereas in others (1, 2, 3, 9, 10, 12, 13, 15) there is a disproportionate elevation in the LPSAP fraction. Subject 7 exhibits the largest contribution of LPSAP (60%). There appears to be no similarity of the heat sensitivities of LPSAP and non-LPSAP in subjects 4, 5, 7, 14, and 15 with total LPSAP hyperphosphatasemia. In fact, the relatively high heat inactivation of sera 5, 6, 7, and 12 would register negatively for liver in a heat-inactivation test of total alkaline phosphatase (P19). 

Constancy of Serum Alkaline Phosphatase Activity in Individual Subjects. 176... 

The measurement of alkaline phosphatase in serum or plasma constitutes one of the most widely employed tests in the clinical chemistry laboratory (Table 1). The subject has been repeatedly reviewed in recent years (FIO, Fll, K5, Mc3, P24, P29). An attempt will therefore be made in this article to list some of the more recent references and to indicate under what circumstances serum alkaline phosphatase measurements are of clinical value. 

The relatively wide variation in serum alkaline phosphatase activities observed in groups of apparently healthy adults (see Table 2) is in sharp contrast to the remarkable constancy of values found over long periods of time in any one subject (Lll, S63, Y3). 

Small but definite diet-induced changes in serum alkaline phosphatase activities have been reported in man. The most noticeable effects occur in association with fat ingestion, particularly in subjects of blood group O and in blood group secretors (K25, W4). Kleerekoper et al. (K25) found a mean rise of 25.6% in the serum alkaline phosphatase values of a group of volunteers 5 hours after a meal of high fat content. This rise was due, predominantly, to the appearance of intestinal alkaline phosphatase in... 

Crosby et al. (C36) measured serum alkaline phosphatase and serum iron in a group of ostensibly normal subjects. High serum iron levels were found in 30 subjects, and 2 of these had serum alkaline phosphatase elevations. Other liver function tests were also abnormal in several subjects with serum iron elevation, and it is likely that at least some of the apparently normal subjects were suffering from subclinical hemochromatosis. 

A 20-day stay at an altitude of 3800 m caused no change in the mean serum alkaline phosphatase activity of 25 volunteers (B20). However, the mean value increased sharply after the subjects returned to sea level and then fell to normal over the following 2 weeks. 

K12) some 50 years ago. Since then, numerous references to the diagnostic significance of serum alkaline phosphatase elevations in disorders of bone have appeared in the literature and the subject has recently been reviewed in detail (Mc3, P29). 

Serum alkaline phosphatase elevation and other indices, both biochemical and radiological, of rickets and osteomalacia are more common in patients receiving anticonvulsant drugs than in control subjects (B13, C16, C37, R16, TIO). The severity of these abnormalities has been reported to relate directly to the duration of therapy (K35, TIO), to the... 

Only one of the eight 1968 dermal-exposure subjects had erythema at the exposure site, which lasted for 7 h. The CN was applied to his skin. Five of the 1968 dermal-exposure subjects had normal results of laboratory analyses—Including urinalysis, complete blood count, blood urea nitrogen, alkaline phosphatase, and serum glutamic oxalotransferase—7 d after exposure. 

Most of the general biochemical results are within normal limits. The blood urea is also normal, except in subjects on a low protein diet, when it is decreased. The blood pH is frequently near the upper limit of normal, and sometimes even above it. Although some liver function tests are normal, the serum GOT, GPT, and the LDH are raised, sometimes markedly, especially when a normal protein diet is taken. The alkaline phosphatase is also usually raised. 

A biochemical evalution of human alkaline phosphatase is postponed until the above considerations have been presented. In our view, the most reasonable analytical approach is based on the measurement of L-phenyl-alanine-sensitive and -insensitive moieties along with their respective heat stabilities. To this may be added information gathered from starch-gel electrophoresis with native and heated serum and from the presence of L-phenylalanine-sensitive bands on the gels following electrophoresis. Experiments of a different type can be included, in which the serum is incubated with neuraminidase and susceptibility of the glycoprotein is established following electrophoresis. Finally, the data on L-phenyl-alanine inhibition of heat-sensitive and -insensitive moieties appear to make sense, if the population of normal subjects is divided into one with the slow-moving intestinal band and one without it. It is from this consideration and other indirect and direct inferences that the intestine is... 

The identity of the slow-moving band observed in all of these studies is the intestine, based on its L-phenylalanine sensitivity (F9, K25, R7, S49, N20, W6) and resistance to neuraminidase (R7). This is even more certain following the demonstration of an elevation in thoracic lymph and in blood serum of L-phenylalanine-sensitive alkaline phosphatase in subjects absorbing fat. The slow-moving band becomes intensified in sera of individuals who are secretors (K7, L2). 

Fia. 32. Starch-gel zymograms of alkaline phosphatase in 6 normal subjects. A, B, and 0 represent the blood types U = unheated, and H = heated serum (16 minutes at 55°C). The upper 3 pairs from left to right belong to subjects 2, 22, and 30 listed in Table 10 (Parts I and II) the lower 3 subjects from left to right are 10, 24, and 17. 

The serum of the normal subject is essentially a mixture of alkaline phosphatase activities, whose total activity is stable but which includes moieties that fluctuate in a manner related to the genetic constitution of the individual. What is the origin of these moieties ... 

It was possible, in the preceding section, to arrive at a biochemical classification in normal healthy subjects. The moieties measured are simply the alkaline phosphatase activity of unheated and heated serum in the presence of n- and L-phenylalanine, respectively. Depending on the individual s blood type, secretor status, and sex, the mean values and relative proportions of each may differ. 

Hsia et ah (H20) found that relatively few patients with cystic fibrosis of the pancreas had detectable intestinal alkaline phosphatase in their serum. They attributed this finding to the malabsorption of fat. However, the mean total values were considerably higher among the patients than among control subjects (H20). 

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