The rabbit prions were developed using the protein misfolding cyclic amplification (PMCA) technique; rabbit brain homogenate, either unseeded or seeded in vitro with disease-related prions obtained from different species, was subjected to serial rounds of PMCA [1]. De novo rabbit prions produced in vitro from unseeded material were tested for infectivity in rabbits, with one of three intra-cere...

1. delta9-Tetrahydrocannabinol and cannabidiol both exhibited a concentration-related inhibition of Mg2+-ATPase of vesicles prepared from synaptosomes isolated from rat cerebral cortex. Cannabidiol was about 3 times more potent than tetrahydrocannabinol. 2. These results were similar to those obtained previously using drugs with well established anticonvulsant activity. 3. Tetrahydrocannabinol ...

We investigated the possible roles of estrogen on plasma membrane Ca(2+)-ATPase (PMCA) in human fibroblast-like synovial cells (HFLS) and mouse macrophage-like cells (RAW 264.7). Western blots revealed the expression of PMCA 2 and 4 in both cells. In vitro treatments with 17beta-estradiol for 24 hours resulted in a concentration dependent decrease in PMCA expression. Moreover, Ca(2+)-ATPase spe...

Wen Zhao, MD, PhD; Qunying Yuan, MD; Jiang Qian, MD; Jason R. Waggoner, PhD; Anand Pathak, PhD; Guoxiang Chu, MD, PhD; Bryan Mitton, BS; Xiaoyin Sun, MD; Jay Jin, BS; Julian C. Braz, PhD; Harvey S. Hahn, MD; Yehia Marreez, MD; Faisal Syed, MD; Piero Pollesello, PhD; Arto Annila, PhD; Hong-Sheng Wang, PhD; Jo El J. Schultz, PhD; Jeffery D. Molkentin, PhD; Stephen B. Liggett, MD; Gerald W. Dorn I...

PrP(Sc) is believed to serve as a template for the conversion of PrP(C) to the abnormal isoform. This process requires contact between the two proteins and implies that there may be critical contact sites that are important for conversion. We hypothesized that antibodies binding to either PrP(c)or PrP(Sc) would hinder or prevent the formation of the PrP(C)-PrP(Sc) complex and thus slow down or ...

The activity of Mg2+-ATPase and Na+-K+-ATPase was measured in media of calcium concentrations ranging from 10(-9)M to 10(-3)M, with retinal homogenates from rat and rabbit. In both species calcium stimulated the Mg2+-ATPase and inhibited Na+-K+-ATPase. In the rat, activity of Na+-K+-ATPase fell by 75% as calcium was increased from 10(-8)M to 10(-7)M and reached 90% inhibition only at 10(-3)M. B...

The ability of prions to infect some species and not others is determined by the transmission barrier. This unexplained phenomenon has led to the belief that certain species were not susceptible to transmissible spongiform encephalopathies (TSEs) and therefore represented negligible risk to human health if consumed. Using the protein misfolding cyclic amplification (PMCA) technique, we were abl...

A fluorescent cholesterol analog, 3'-pyrenylmethyl-23,24-dinor-5-cholen-22-oate-3 beta-ol (PMCA), has been synthesized as a spectroscopic probe of cholesterol function. The substrate activity of PMCA, about two-thirds that of cholesterol, with lecithin:cholesterol acyltransferase indicates that PMCA is a reasonable cholesterol analog and that the orientation of the substituted sterol in the pho...

Epithelial junctions depend on intercellular interactions between β(1) subunits of the Na(+)/K(+)-ATPase molecules of neighboring cells. The interaction between dog and rat subunits is less effective than the interaction between two dog β(1) subunits, indicating the importance of species-specific regions for β(1)-β(1) binding. To identify these regions, the species-specific amino acid residues ...

Two-dimensional infrared correlation spectroscopy (2D-IR) was applied to the study of urea- and heat-induced unfolding denaturation of sarcoplasmic reticulum Ca(2+)-ATPase (SR ATPase). Urea at 2-3 M causes reversible loss of SR ATPase activity, while higher concentrations induce irreversible denaturation. Heat-induced denaturation is a non-two-state process, with an "intermediate state" (at t a...