Changes in resting membrane potential induced by active sensitization in the guinea-pig vas deferens.

Smooth muscles hyperresponsiveness is a common feature in anaphylaxis and allergic diseases. The aim of the present work was to investigate whether the enhanced reactivity of sensitized guinea-pig vas deferens was associated with changes in the resting membrane potential (Er) of the smooth muscle cells. Active sensitization was performed by subcutaneous injection of egg albumen.

Loss of nitric oxide release in passively sensitized guinea-pig aorta with purified immunoglobulin G1.

Background: Vascular hyperresponsiveness can be reproduced by in vitro passive sensitization of isolated aorta with immunoglobulin G1 (IgG1) taken from ovalbumen-sensitized BFA guinea-pig.

Objective: The aim of the present work was to investigate the role of nitric oxide in the sensitization-induced alteration of the contractile and relaxant responses of guinea-pig aorta to noradrenaline (NA) and acetylcholine (ACh), respectively.

Methods: Cumulative concentration-response curves to NA or ACh were established before and after IgG1 sensitization and then after successive treatments.

Effect of guinea-pig purified immunoglobulin G1 on the responsiveness of tracheal, aortic, vas deferens and ileum smooth muscles.

Background: Smooth muscles hyperresponsiveness is a common feature in anaphylaxis and allergic diseases.

Objective: The aim of the present work was to investigate the effect of in vitro passive sensitization with highly purified immunoglobulin G1 (IgG1) on the responsiveness of tracheal, aortic, vas deferens and ileum smooth muscles.

Methods: Firstly, IgG1, obtained from actively sensitized BFA guinea-pigs, was purified by Protein A-Sepharose column and characterized by enzyme-linked immunosorbent assay (ELISA) and immunoelectrophoresis analysis.

Effect of moderate cooling on contractile responses in mouse vas deferens and its relation to calcium.

Isolated mouse vas deferens preparations were used to study the effect of temperature on noradrenaline-induced contractions. Preparations were suspended in the organ bath containing Krebs-Henseleit solution for isometric tension recording. Contractile responses to noradrenaline were investigated in the mouse vas deferens after moderate cooling from 37 to 26 or 22 degrees C.

Effect of temperature reduction on the vas deferens hyperresponsiveness of sensitized mice.

1. The present study was designed to investigate the effect of active sensitization on the responsiveness of mouse vas deferens before and after moderate cooling. Contractile responses to noradrenaline (NA) were isometrically recorded in the vas deferens of control and ovalbumen-sensitized mice at 37 degrees C and 22 degrees C.