Correlation between 2,3-diphosphoglycerate and red cell mass in the third trimester of pregnancy

In 30 non-anemic, and in 7 non-thalassemic, anemic pregnant women the red cell mass (RCM) was determined at 32-36 weeks of pregnancy, using isotopes, and was correlated with red cell 2,3-DPG, using the method of Keitt. The increase in 2,3-DPG in pregnant women with low RCM was in the same range as in those with increased RCM. Thus, 2,3-DPG can not be used to diagnose a RCM deficit in pregnancy. The relationship between 2,3-DPG and RCM in the third trimester was complex: in the 7 anemic women there was an inverse relationship, which failed to reach statistical significance, probably because of the small number of cases; in the 30 non-anemic women there was a significant, positive correlation between 2,3-DPG and RCM. The cause of this positive relationship needs further investigation.

Neoantigen of the polymerized ninth component of complement. Characterization of a monoclonal antibody and immunohistochemical localization in renal disease

A monoclonal antibody to a neoantigen of the C9 portion of the membrane attack complex (MAC) of human complement has been developed and characterized. The distribution of this neoantigen was assessed by indirect immunofluorescence microscopy in nephritic and nonnephritic renal diseases. The antibody (Poly C9-MA) reacted on enzyme-linked immunosorbent assay (ELISA) with a determinant in complement-activated serum that was undetectable in normal human serum (NHS). Zymosan particles incubated in NHS had positive immunofluorescent staining with Poly C9-MA; however, binding of Poly C9-MA was not observed with zymosan particles incubated in sera deficient in individual complement components C3, C5, C6, C7, C8, or C9. Reconstitution of C9-deficient sera with purified C9 restored the fluorescence with Poly C9-MA. Poly C9-MA reacted positively by ELISA in a dose-dependent manner with purified MC5b-9 solubilized from membranes of antibody-coated sheep erythrocytes treated with NHS but not with intermediate complement complexes. Poly C9-MA also reacted in a dose-dependent manner on ELISA and in a radioimmunoassay with polymerized C9 (37 degrees C, 64 h) (poly C9) but not with monomeric C9. Increasing amounts of either unlabeled poly C9 or purified MC5b-9 inhibited the 125I-poly C9 RIA in an identical manner. These studies demonstrate that Poly C9-MA recognizes a neoantigen of C9 common to both the MAC and to poly C9. By immunofluorescence, Poly C9-MA reacted minimally with normal kidney tissue in juxtaglomerular loci, the mesangial stalk, and vessel walls. Poly C9-MA stained kidney tissue from patients with glomerulonephritis in a pattern similar to that seen with polyclonal anti-human C3. In tissue from patients with nonnephritic renal disease--diabetes, hypertension, and obstructive uropathy--Poly C9-MA was strongly reactive in the mesangial stalk and juxtaglomerular regions, tubular basement membranes, and vascular walls. Poly C9-MA binding was especially prominent in areas of advanced tissue injury. Poly C9-MA frequently stained loci where C3 was either minimally present or absent. These studies provide strong evidence for complement activation not only in nephritic but also in nonnephritic renal diseases.

Myocardial protection by lidocaine during cardioplegia

This study was undertaken to examine the effects of lidocaine (L) (400 mg/liter) in a normokalemic crystalloid (S) (K +: 5 meq/liter, Na+: 120 meq/liter) and in a hyperkalemic crystalloid cardioplegic solution (K) (K+: 25 meq/liter, Na+: 120 meq/liter) during 90 min of hypothermic (28 degrees C) aortic occlusion followed by 45 min of reperfusion (R). Four groups of dogs were studied: group 1 (S), n = 6; group 2 (S + L), n = 6; group 3 (K), n = 6; group 4 (K + L), n = 6. Left ventricular (LV) function was defined as percentage changes in center of mass between pre- and postarrest function curves. Regional myocardial flow was measured with 9 mu radioactive microspheres and myocardial metabolism monitored by lactate and oxygen utilization. Ventricular biopsies were obtained for measurement of myocardial ATP, creatine phosphate, and water content. Percent recovery of LV function curves at the end of (R) was 59.2 +/- 3.9% in group 1, 85.0 +/- 4.3% in group 2, 71.5 +/- 4.9% in group 3, and 87.0 +/- 4.5 in group 4 (group 1 vs group 2, P less than 0.01; group 3 vs group 4, P less than 0.05). Metabolic recovery was evaluated at 5, 20, and 45 min of (R). Only group 3 (K) demonstrated persistent lactate production at 5 min of (R) (P less than 0.01). The hyperkalemic groups failed to return to control levels of oxygen utilization after 5 min of (R) (group 3, P less than 0.05; group 4, P less than 0.05). LV endocardial/epicardial myocardial blood flow ratio demonstrated greater increase in hyperkalemic groups (group 3, P less than 0.01; group 4, P less than 0.01) at 5 min of (R). ATP was significantly decreased in groups 1, 3 and 4, but not in group 2 at the end of ischemia (group 1, P less than 0.01; group 3, P less than 0.01; group 4, P less than 0.05) and after 45 min of (R) (group 1, P less than 0.05; group 3, P less than 0.01; group 4, P less than 0.01). These results demonstrate that lidocaine has a myocardial protective effect which is superior to standard hyperkalemic cardioplegia. Moreover, lidocaine has an additive salutary effect during potassium cardioplegia. Persistent metabolic derangements post reflow in the hyperkalemic groups suggest deleterious effects of hyperkalemia on subendocardial protection.

Effect of the pH of cardioplegic solution on postarrest myocardial preservation

The assumption that an alkaline cardioplegic solution is advantageous to the arrested heart is not supported by experimental evidence. Three groups of dogs were subjected to 2 hours of hypothermic arrest using a potassium cardioplegic solution of varying pH: group 1 (n = 8), pH 7.1; group 2 (n = 6), pH 7.4; and group 3 (n = 8), pH 7.7. Left ventricular (LV) function curves were obtained before arrest and after reperfusion, and the percent recovery of LV function was calculated. Coronary blood flow (CBF), oxygen and lactate use, and adenosine triphosphate and creatine phosphate were measured before and after arrest. Recovery of LV function was 83 +/- 4% (mean +/- SEM) in group 1 and 75 +/- 6% in group 2. LV function in group 3 was significantly depressed at 51 +/- 5% (p less than 0.01). Immediately after arrest, CBF and oxygen consumption were lowest in group 1 and highest in group 3 (p less than 0.01). CBF increased 23 +/- 9% in group 1, 110 +/- 29% in group 2 and 277 +/- 33% in group 3. Oxygen consumption was 2.2 +/- 0.4 vol/100 g/min in group 1, 3.63 +/- 0.5 vol/100 g/min in group 2 and 4.63 +/- 0.7 vol/100 g/min in group 3. All groups showed postarrest depression of adenosine triphosphate and creatine phosphate, but return of creatine phosphate to control was slowest in group 1 (p less than 0.01). These results indicate no advantage to an alkaline cardioplegic solution and suggest that an acidic cardioplegic solution, by inhibiting metabolism, may increase protection of the arrested heart.

Production of 17-hydroxypregnenolone and 17-hydroxyprogesterone by the immature rat ovary

The concentration of 17-hydroxyprogesterone (17-OH-prog), but not 17-hydroxypregnenolone (17-OH-preg), was detectable in the sera of 5 day old female rats. The level of 17-OH-preg increased dramatically between day 5 and 10, remained high for 5 days and then decreased to low levels by day 25; a second increase was found on day 35. 17-OH-prog began to increase in the serum after day 10, reached a peak by day 20 and then decreased by day 25 and remained the same through day 35. Stimulation of the ovaries of intact females with 20 IU of pregnant mare's serum gonadotropin resulted in a prompt increase in both progestins, but a much larger increase in 17-OH-preg than in 17-OH-prog. Increases were similar, but quantitatively less, in hypophysectomized females. The results demonstrate that the ovaries of immature rats contain an active 17-hydroxylase system.

Cellular retinol-binding protein and retinoic acid-binding protein in rat testes: effect of retinol depletion

Testes of rats contain two cellular binding proteins of interest in vitamin A metabolism. One protein binds retinoic acid with high specificity; the other binds retinol with high specificity. When the cellular retinol-binding protein was partially purified from rat testes, it exhibited fluorescence excitation and emission spectra similar to that of all-trans-retinol in hexane. Exposure of this preparation to UV light destroyed this fluorescence but spectra identical to the original were obtained after addition of retinol. Hexane extracts of the binding protein had fluorescence spectra identical to all-trans-retinol, suggesting that this compound is bound to the protein in vivo. Extracts of testes from retinol depleted rats were submitted to gel filtration but failed to show a retinol-like fluorescence at the elution position of retinol binding protein. This fluorescence was observed in the preparations from pair fed control animals. However, after addition of all-trans-retinol to the extracts from the depleted rats, fluorescence at that elution position was observed. This indicates that in testes of retinol depleted rats the cellular retinol binding protein is present but without bound retinol, in contrast to the non-depleted rats where 30-43% of the binding protein had bound retinol. The amounts of cellular retinol binding protein and retinoic acid binding protein in testes, as determined by sucrose gradient centrifugation, were found to be similar for retinol depleted and pair fed control rats.