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Stress induced by routine cage cleaning causes retention of Na+ and K+, and increased water and prostaglandin metabolite excretion when measured either against concurrent-controls or against self-control values. This novel stress completely masked the diuretic effects of a long-acting prostaglandin synthetase inhibitor previously observed in a stress-free environment. The results show that prostaglandin synthesis and urine volume regulation are closely associated. They also demonstrate a complete dissociation of urine volume and prostaglandin synthesis regulation from electrolyte regulatory mechanisms in a stressful environment.

Extraction of calf anterior and posterior lens capsules with 5 M guanidine HCI resulted in the solubilization of protein (12% of total) with a noncollagenous amino acid composition leaving behind the collagen matrix. Polyacrylamide gel electrophoresis of the solubilized material revealed a number of components, all of which were susceptible to trypsin but resistant to collagenase digestion. Fractionation of the extracted proteins by Sepharose CL-6B filtration as well as by affinity chromatography was undertaken, and laminin, fibronectin, entactin, and beta-crystallin were identified by electrophoresis and solid-phase radioimmunoassays in both anterior and posterior capsules. An entactin (Mr = 150,000), which constituted the most prominent component on electrophoresis, was purified after Sepharose CL-6B filtration by a two-step lectin affinity chromatography procedure, which was based on the failure of this protein to bind to Bandeiraea simplicifolia I but its positive reactivity with wheat germ lectin. Neither the mixture of proteins extracted from lens capsules by guanidine nor fractions prepared therefrom were able to enhance lens epithelial cell attachment to type I or type IV collagen-coated surfaces or to guanidine-prepared lens capsules; adhesion-stimulating activity could not be demonstrated even when cycloheximide-treated cells were employed. Furthermore, the cells were observed to attach as effectively to guanidine-extracted as to native capsules. These observations indicate that noncollagenous proteins are not essential for the in vitro attachment of epithelial cells to lens capsule; it appears that the collagen component itself provides an optimal surface for cell-basement membrane interaction.

The normal human fibroblast, WI-38, was labelled with radioactive mannose and its incorporation, as well as the accumulation of acidic and neutral glycopeptides on the cell surface, was followed as a function of time. The transit time of newly made Pronase-released cell surface glycopeptides from their intracellular site of synthesis to the cell surface was slower in nongrowing cells than in a rapidly growing culture. When the surface glycopeptides were separated by high-voltage paper electrophoresis into neutral and acidic species, it was observed that the cell surface material was initially enriched with neutral glycopeptides. However, with time the relative proportion of acidic species increased so that by 3 h the ratio between the acidic and neutral species approached a constant value. Our data are consistent with the hypothesis that multiple pathways for asparagine-linked glycoprotein biosynthesis are possible.

Matching of donors and recipients in cases of B cell chronic lymphocytic leukemia (CLL) is complicated by the fact that the cancer clone dominates the blood. A case of CLL was characterized for its antigenic phenotype using monoclonal antibodies. Iron beads were coated with the appropriate antibody and used to remove the cancer clone. A mixed lymphocyte culture (MLC) utilizing the purified cells as well as unpurified cells and sheep cell rosetted purified cells was performed with the donor. Using coated beads, the T cell population rose from 8% to 95% in one treatment versus 8% to 42% with sheep cells. MLC data were statistically better with bead-treated cells, and the results demonstrated the importance of this technique for transplantation matching.

Adhesion of calf lens epithelial cells to lens capsule, their natural basement membrane was found to be considerably more rapid than either to plastic or to type I or type IV collagen coated surfaces. No polarity of the basement membrane was observed as the cells were able to attach to either side of the anterior or posterior lens capsule; a prerequisite for adhesion to the lenticular side of the anterior capsule was the prior removal of its epithelial cell layer. The attachment was energy-dependent and required calcium and magnesium ions, but was not enhanced by the presence of serum. Neither exogenous fibronectin nor laminin was able to stimulate attachment or spreading of lens cells to the capsule even when the cells had been treated with cycloheximide. Since rapid adhesion and spreading takes place in this lens cell-lens capsule system without requirement of exogenous macromolecules, it provides a favorable model for investigating the determinants in epithelial cell-basement membrane interactions.

Fifty-two steroids, structurally related to spironolactone, were tested for their ability to alter excretion of urinary prostaglandin-E metabolites (U-PGE-M). We found that steroids which are associated with elevation or depression of blood pressure will elevate or depress basal levels of U-PGE-M in the rat. Structural requirements for elevation or depression of metabolites are narrow and sensitive to slight conformational changes in either the C-17 side chain or the steroid nucleus. Metabolite-elevating steroids share a common basic conformation, and metabolite-depressing steroids share a different common basic conformation. These two basic conformations differ chiefly in the C-17 side chain. The conformational requirements are analogous to the specificity shown by hormone receptors or by enzymes. A strong association of urine volume with U-PGE-M (r = -0.93) was demonstrated in rats treated with spironolactone. A possible explanation relating these results to alteration of blood pressure was presented.

Mannose-labeled cellular glycopeptides derived from human diploid fibroblasts (KL-2) were separated into two classes by QAE-Sephadex chromatography. High-voltage paper electrophoresis and Sephadex G-50 chromatography were used to characterize the glycopeptides further. At least five distinct neutral fractions were isolated with molecular weights ranging from 1050 to 2000 daltons. A linear gradient of ammonium acetate eluted a heterogeneous population of acidic glycopeptides. The use of QAE-Sephadex enables a single-step fractionation of both neutral and acidic glycopeptides on one column. The technique appears to be sensitive enough to distinguish growth-dependent alterations between growing and non-growing cells.

In both primary and secondary infections using 3 different strains of mice (DBA/1, B10 X D2, and C3H/HeJ), 2 peaks of peripheral blood eosinophilia were noted. Depending upon the strain, the first of the biphasic peaks in primary infections occurred between days 5 and 9, and the second peak occurred between days 16 and 22. The relative heights of the peak varied with the strain. In secondary infections, the initial peak was lower and the larger second peak occurred earlier. Methyridine treatment to eliminate adults prior to release of newborn larvae altered neither the course of eosinophilia in primary infection nor the biphasic distribution of eosinophilia. These studies demonstrate that the adult worm is responsible for inducing eosinophilia in murine infections, that 2 peaks of eosinophilia exist in primary and secondary infections, and that eosinophilia in secondary infections is an anamnestic response.