Context: Although it is well established that thyrotropin (TSH) initiates signal transduction systems resulting in protein kinase(s) activation, the phosphorylated targets have not been fully characterized.
Objective/design: In FRTL-5 thyroid cells, we used two-dimensional (2D) gel images of silver-stained proteins isolated from FRTL- 5 thyroid cells following TSH stimulation to identify potential phosphorylation targets.
Results: We characterized a 90 kDa protein that had undergone a pH shift and subsequently identified it as heat shock protein-90 (hsp-90) following in-gel trypsin digestion and mass spectroscopy.
Parathyroid hypertensive factor (PHF) is a newly described hypertensive factor isolated from the plasma of spontaneously hypertensive rats (SHR). Recent studies have suggested that the primary origin of PHF is the parathyroid gland (PG). In the present investigation, PG from spontaneously hypertensive rats (SHR), as well as from normotensive rats, were isolated and maintained in culture.
View Article and Find Full Text PDFIn fresh-water rainbow trout, Oncorhynchus mykiss (formerly called Salmo gairdneri), experimentally induced mild hypercalcemia results in release of immunoreactive stanniocalcin from the corpuscles of Stannius (CS) and stimulated synthetic and releasing activities of the glands as measured in vitro. Pulse-chase experiments showed that stanniocalcin (STC) is a 56-kDa glycoprotein, processed from a 64-kDa precursor, prostanniocalcin (PSTC). PSTC and STC are homodimeric molecules that are readily split into monomers in the presence of reducing agents such as 2-mercaptoethanol.
View Article and Find Full Text PDFCalcitonin gene-related peptide (CGRP) was found extensively in the small intestine of both non-mammalian and mammalian vertebrates using radioimmunoassay and immunocytochemistry. By radioimmunoassay, the levels of CGRP in rats, mice, chickens, bullfrogs and rainbow trout were found to range from 91.5 to 419.
View Article and Find Full Text PDFHypercalcemia (induced by CaCl2-injection or seawater exposure of the fish) reduced the hypocalcin content of corpuscles of Stannius (CS) in trout, goldfish and eel; concomitantly the synthetic activity of CS of hypercalcemic fish, as determinedin vitro, was enhanced. The monomeric forms of prohypocalcin and of hypocalcin of trout and goldfish are 32 and 28 kDA Mr glycoprotein species respectively; those of the eel are 2 kDa bigger,viz. 34 and 30 kDa respectively.
View Article and Find Full Text PDFHighly specific antisera were raised against hypocalcin, a 54-kDa glycoprotein purified from the corpuscles of Stannius (CS) of rainbow trout, Salmo gairdneri. The specificity of the antisera was determined by using Ouchterlony's double immunodiffusion test, radioimmunoassay (RIA), enzyme-linked immunosorbent assay (ELISA), and immunocytochemistry. In the double immunodiffusion test, a single precipitin line was formed between the antisera and hypocalcin.
View Article and Find Full Text PDF1 A new synthetic bradykinin analogue was found to be an antagonist of bradykinin-induced vascular permeability in rabbit skin. It was effective in equimolar concentrations. 2 These analogues also antagonized the action of bradykinin in contracting the guinea-pig isolated ileum.
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