Beta-2 adrenoceptors in blood vessels are one of the active factors that play a role in regulation of tissue blood flow. in diabetic angiopathy, responsiveness of these receptors is decreased, while that is increased in inflammation. According to these opposite effects, the aim of this study was to investigate the vasodilatory response of knee joint blood vessels to salbutamol (Beta-2 adreno...

G-protein-coupled receptors (GPCRs) mostly signal through heterotrimeric G proteins. Increasing evidence suggests that GPCRs could function in a G-protein-independent manner. Here, we show that at low concentrations of an agonist, beta(2)-adrenergic receptors (beta(2)-ARs) signal through Galpha(s) to activate the mitogen-activated protein kinase pathway in mouse embryonic fibroblast cells. At h...

A randomised double-blind crossover study was undertaken in 25 patients with variable airflow obstruction to assess the benefit of separating the inhalation of beta-agonist aerosols and corticosteroid aerosols by a timed interval of more than five minutes. Twenty-two patients (11 men and 11 women) completed 12 weeks of study; they inhaled 200 micrograms salbutamol followed either immediately or...

Sixteen patients with stable chronic asthma participated in a double blind crossover study comparing the new inhaled long acting beta 2 agonist formoterol with salbutamol. Inhaled (n = 15) and oral steroid (n = 1) treatment were maintained at the same daily dose throughout the study. For four weeks the patients received either formoterol 24 micrograms twice daily or salbutamol 400 micrograms tw...

transcutaneous electrical nerve stimulation (tens) is an analgesia inducing method with increasing applications in clinical procedures. in this study we tried to evaluate the role of the adrenergic system and its different adrenoceptor subtypes in tens-induced analgesia. two types of low and high frequency electrical stimuli were used in rats through needle electrodes, inserted at the base of t...

Activation of phospholipases leads to the release of arachidonic acid and lysophospholipids that play prominent roles in regulating vasomotor tone. To identify the role of calcium-independent phospholipase A(2)beta (iPLA(2)beta) in vasomotor function, we measured vascular responses to phenylephrine (PE) and ACh in mesenteric arterioles from wild-type (WT; iPLA(2)beta(+/+)) mice and those lackin...

Heptahelical receptors that interact with heterotrimeric G proteins represent the largest family of proteins involved in signal transduction across biological membranes. Although these receptors generally were believed to be monomeric entities, a growing body of evidence suggests that they may form functionally relevant dimers. However, a definitive demonstration of the existence of G protein-c...

Desensitization of cannabinoid receptor signaling by a G-protein coupled receptor kinase (GRK) was examined using the Xenopus oocyte expression system. Application of a CB1 agonist, WIN 55,212-2, evoked a concentration-dependent increase in K+ conductance (Kir3) in oocytes coexpressing rat CB1 with the G-protein-gated, inwardly rectifying K+ channels Kir3.1 and Kir3.4. Desensitization was sligh...

Infant rat ultrasonic vocalizations (USVs) are widely believed to result from the induction of an emotional state of anxiety or distress. This perspective, however, is not easily reconciled with the demonstration by W. J. Farrell and J. R. Alberts 2000 that norepinephrine, a nonselective beta-adrenoceptor agonist with anxiogenic properties, inhibits production of USVs. Here, Farrell and Alberts...