K+ potentiates hyperosmolarity-induced vasorelaxations in rat skeletal muscle arterioles.

Several regulatory mechanisms have been proposed for the exercise hyperemia in skeletal muscles. Since different vasoactive factors might interact during the hyperemic response, we investigated the influence of elevated K(+) concentrations on hyperosmolarity (HO)-induced vasorelaxations. Small gluteal rat arteries were isolated and mounted in an organ bath for isometric tension recording.

The measurement of competitive anxiety during balance beam performance in gymnasts.

The purpose of the present study was to investigate competitive anxiety during balance beam performance in gymnasts. Competitive anxiety was assessed continuously by heart rate monitoring and by retrospective self-report of nervousness in eight female national level gymnasts during their balance beam routine during one competition and two training sessions. A significant negative correlation was found between the score of the retrospective self-report of nervousness and performance during the routine.

Hyperosmolarity causes BK Ca-dependent vasodilatations in rat skeletal muscle arteries.

Purpose: The release of different metabolites during skeletal muscle contraction causes a pronounced increase in extracellular osmolarity (hyperosmolarity (HO)). HO has been considered as a possible mediator of the exercise hyperemia. In the present study, we investigated the vasodilatory effect of physiologically relevant increases in the extracellular osmolarity in isolated rat gluteal muscle arterioles.

Hyperosmolarity increases K+-induced vasodilations in rat skeletal muscle arterioles.

Purpose: Exercise hyperemia is mediated by a multitude of vasoactive metabolites released from the active skeletal muscle. Because several vasoactive factors might interact during the hyperemia response, we investigated the influence of hyperosmolarity (HO) on K(+)-induced relaxations.

Methods: Small gluteal rat arteries (diameter: 245 +/- 6 microm) were isolated and mounted in an organ bath for isometric tension recording.

Potassium potently relaxes small rat skeletal muscle arteries.

Introduction: Skeletal muscle contraction elicits an explosive rise in interstitial potassium (K+) concentration. K+ has been considered as one of the most potent vasoactive metabolites in skeletal muscle arterioles. Studies on isolated blood vessels report large relaxations when extracellular [K+] is increased up to 10 mM.