Development and evaluation of an immunoenzymometric assay for the chicken progesterone receptor.

A specific and sensitive immunoenzymometric assay (IEMA) was developed for measuring the quantity of chicken progesterone receptor (PR) in tissue cytosol. The assay uses two monoclonal antibodies to the PR. One is used to capture the PR. The second (labelled with biotin) reacts first with the captured receptor and subsequently with avidin-labelled horseradish peroxidase to provide an enzymatic end-point. The method has a determination range from 0.3 to 60 pmol/l. Intra- and interassay coefficients of variation were 3.7% and 9.0% respectively. The assay can be performed with equal results as a rapid (3 h) or an overnight procedure. The IEMA is convenient, especially for signal measurement and the calculation of results. No ultracentrifugation of samples is needed, since the IEMA can be performed on low-speed cytosol samples. Assay results correlated well (r = 0.927) with those obtained by the conventional ligand-binding assay used in our laboratory. Similar results were obtained with the IEMA and the ligand-binding assay after exposure of cytosol samples to increased temperatures: at 20 degrees C the PR remained stable for the 4-h period examined, whereas at 37 degrees C almost complete degradation of the PR was observed in 30 min. Being more than 100 times as sensitive as the ligand-binding assay, the IEMA enabled the quantification of PR for the first time in such tissues as the bursa and small intestine even of immature animals.

Characterization of the estrogen-sensitive cells expressing progesterone receptor in the bursa of Fabricius.

Cells expressing the progesterone receptor (PR) in the bursa of Fabricius (BF) were studied with immunohistochemistry at light-microscopic level, with immunoelectron microscopy (immuno-EM) and with non-specific esterase histochemistry. The antibody (IgG-RB) directed to the B component of the chick oviduct progesterone receptor was shown by immunoblotting to be specific for the PR and to recognize the PR also in the bursa. Two cell types in the BF contain the PR: stromal cells in the interfollicular-subepithelial area and smooth muscle cells lining the BF. The PR was localized in the nuclei of these cells. The bursal epithelium and the cells inside the follicles were not stained for PR. Electron microscopically the immunoreaction precipitate was localized on condensed heterochromatin and on dispersed euchromatin. The cells expressing the PR resembled electron microscopically fibroblasts. Their cytoplasm was rich in rough endoplasmic reticulum indicating active protein synthesis. By non-specific esterase histochemistry we showed that the PR-containing cells were not macrophages, which are morphologically indistinguishable from stromal cells. In the bursae of young untreated chicks the PR was not seen, but was inducible by estradiol treatment and was spontaneously expressed after the onset of sexual maturation. It is concluded that both the stromal fibroblasts and the smooth muscle cells in the BF are estrogen and progesterone sensitive. The expression of PR after the onset of sexual maturation indicates that the BF is directly affected by sexual maturation-associated factors. We suggest that estrogen and progesterone participate in tissue remodelling during bursal involution via the stromal cells and may affect bursal functions via the smooth muscle cells.

The effects of glycopyrrolate on oral mucous host defenses in healthy volunteers.

UNLABELLED: We studied the effects of glycopyrrolate on oral mucous host defenses. Single IV doses of glycopyrrolate (4 microg/kg) or placebo were administered to 12 healthy volunteers in a randomized, double-blinded, cross-over study. Salivary flow rates and the concentrations/activities of total protein, amylase, and nonimmunologic (lysozyme, lactoferrin, myeloperoxidase, total salivary peroxidase, and thiocyanate) and immunologic (total immunoglobulin A, immunoglobulin G, and immunoglobulin M) mucous host defense factors were determined for paraffin-stimulated whole saliva before and 1, 3, 6, 12, 24, and 48 h after drug administration. Glycopyrrolate serum concentrations were determined before and 2, 4, 6, 10, 15, and 30 min and 1, 2, 3, 6, 12, and 24 h after IV drug injection. Salivary flow rates were decreased significantly for 12 h after glycopyrrolate injection, compared with saline injection. The concentrations of immunologic and nonimmunologic defense factors were increased in the glycopyrrolate group, and differences between the groups were found for all factors (P < 0.05-0.001) except lysozyme and total salivary peroxidase. In contrast, because of the reduced flow rate, the output of all defense factors into the saliva was decreased after glycopyrrolate injection, compared with saline injection. Glycopyrrolate thus decreases the output of salivary host defense factors into the oral cavity. IMPLICATIONS: Glycopyrrolate induces long-lasting hyposalivation and decreases the secretion of salivary immunologic and nonimmunologic defense factors in healthy volunteers.