Localized elaboration of IgA in normal and neoplastic murine mammary cell cultures: relationship to fibronectin matrix.

IgA secretion by the lactating mammary gland culminates a complex sequence of biologic events both within the gland and at distant sites. Because of the many extraglandular influences, it is difficult to investigate IgA secretion at the tissue and cellular levels in the intact animal. In this study, with the use of immunohistofluorescence, we have observed elaboration of IgA by primary monolayer cultures of mammary cells from the glands of mid-pregnant mice and from mammary tumors.

Cyclic AMP-dependent control of the rat hepatic glutathione disulfide-sulfhydryl ratio.

The disulfide-sulfhydryl ratio of rat hepatic tissue has been found to vary diurnally lowest in the early morning and highest in the early evening (Isaacs, J. (1976) Fed. Proc.

Glutathione dependent control of protein disulfide-sulfhydryl content by subcellular fractions of hepatic tissue.

The disulfide-sulfhydryl (SS/SH) ratios of subcellular fractions of rat hepatic tissue were found to vary diurnally with the ratio lowest in the early morning and highest in the early evening. These changes were found in the nuclear, microsomal and cytosol fractions. The primary reaction is the reversible formation of mixed disulfides of glutathione with proteins.

Plasma concentrations of connective tissue compounds: I. the effect of uterine involution.

The information obtained in a prospective study of plasma concentrations of connective tissue components during the third trimester of pregnancy, 4 days, and again at 6 weeks postpartum, suggests that the increased concentrations of plasma protein-hydroxyproline (hypro-protein), free proline, and GAG are associated with increased rate of hydrolysis of extraskeletal connective tissue components.

Brush border particulates of renal tissue.

Particulates containing a large part of the alkaline phosphatase activity of renal tissue were separated from homogenates and from ribosomal preparations by zonal centrifugation. The particles had a high content of phospholipid and cholesterol that was not removed by treatment with I percent deoxycholate. Enzymatic activities concentrated with the particles were the alkaline phosphatase, a peptidase resistant to proteolysis, glucose-6-phosphatase, inorganic pyrophos-phatase, and adenosine triphosphatase.