Price Convergence in the Enlarged Internal Market

In this paper we investigate the effects of EU enlargement on price convergence. The internal market is expected to boost integration and increase efficiency and welfare through a convergence of prices in product markets. Two principal drivers are crucial to explain price developments. On the one hand, higher competition exerts a downward pressure on prices because of lower mark ups. On the other hand, the catching up process of low income countries leads to a rise in the price levels and higher inflation over a transition period. Using comparative price levels for 41 product categories price convergence can be established. However, the speed of convergence is rather slow, with half lives around 10 years. The enlargement has slightly stimulated convergence towards the mean price, and this impact is robust across different groups of countries. Moreover, the driving forces of convergence are explored. In line with theoretical predictions, the rise in competition exerts a downward pressure on prices, while catching up of low income countries leads to a rise in price levels and higher inflation. The findings have important implications, as price convergence facilitates the working of common economic policies

Augmented stress-induced alcohol drinking and withdrawal in mice lacking functional natriuretic peptide-A receptors

AIMS: Preclinical and clinical data suggest an involvement of atrial natriuretic peptides (ANP) in alcohol-associated psychopathology. We now present first data on alcohol drinking behaviour in mice lacking a functional natriuretic peptide-A (NPR-A) receptor. METHODS: NPR-A(-/-) and wild-type mice were given a free choice between water and increasing concentrations of alcohol (2-16%). A forced swim stress was performed thereafter on three consecutive days to investigate stress-induced alcohol drinking. Additionally, neurobehavioural alcohol withdrawal response was investigated following 14 days of forced-alcohol intake. RESULTS: Whereas basal alcohol intake did not differ between NPR-A mutants and wild-type littermates, NPR-A mutants showed an increased stress-induced alcohol intake and aggravated neurobehavioural symptoms of alcohol withdrawal. CONCLUSIONS: Mice lacking a functional NPR-A receptor represent a useful model to study the role of the ANP system in alcohol-associated pathology. To study the role of the natriuretic NPR-A gene for the modulation of risk of alcohol-related disorders, NPR-A-related polymorphisms should be targeted in clinical studies

Effects of cyclothiazide on GluR1/AMPA receptors

Cyclothiazide (CTZ), a positive allosteric modulator of ionotropic α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)-type glutamate receptors, is used frequently to block the desensitization of both native and heterologously expressed AMPA receptors. Specifically, CTZ is known to produce a fast inhibition of AMPA receptor desensitization and a much slower potentiation of the AMPA current. By using patch-clamp techniques, the effects of CTZ were studied in HEK 293 cells stably transfected with the rat flip GluR1 subunit. Upon CTZ treatment, we found an increased apparent affinity for the agonist, a slow whole-cell current potentiation, a fast inhibition of desensitization, and a lengthening of single-channel openings. Furthermore, we show that CTZ alters the channel gating events modifying the relative contribution of different single-channel classes of conductance (γ), increasing and decreasing, respectively, the contributions of γ(M) (medium) and γ(L) (low) without altering that of the γ(H) (high) conductance channels. We also present a kinetic model that predicts well all of the experimental findings of CTZ action. Finally, we suggest a protocol for standard cell treatment with CTZ to attain maximal efficacy of CTZ on GluR1 receptors