The vasodilator activity of a1-adrenoceptor agonists was tested in the rat mesenteric vascular bed (MVB), and the mechanism involved was investigated in cultured endothelial cells isolated from the bovine coronary vascular bed. In preparations preconstricted by U46619, noradrenaline and phenylephrine induced a slight relaxant effect at nanomolar concentrations. This effect was abolished in endo...

Different pharmaceutical preparations against the common cold containing acetaminophen, phenylephrine hydrochloride, and chlorpheniramine have been studied. An unidentified degradation product has been discovered in these preparations after short- and long-term stability studies, with increasing concentration at increasing storage temperatures and times. LC/MS was employed to identify and obtai...

Cardiovagal baroreflex sensitivity (BRS) declines with advancing age in healthy men. We tested the hypothesis that oxidative stress contributes mechanistically to this age-associated reduction. Eight young (23 +/- 1 yrs, means +/- SE) and seven older (63 +/- 3) healthy men were studied. Cardiovagal BRS was assessed using the modified Oxford technique (bolus infusion of 50-100 microg sodium nitr...

The aim of the present study was to investigate the effect and possible mechanism of action of zingerone, the main constituent of ginger, on vascular reactivity in isolated aorta from diabetic rats. The results show that incubation of aortae with zingerone alleviates the exaggerated vasoconstriction of diabetic aortae to phenylephrine, as well as the impaired relaxatory response to acetylcholin...

Objective. To investigate mydriatic effect of intracamerally injected epinephrine hydrochloride during phacoemulsification and intraocular lens (IOL) implantation. Methods. Eighteen cataract patients for bilateral phacoemulsification were enrolled. To dilate pupil, one eye was randomly selected to receive intracamerally 1 mL epinephrine hydrochloride 0.001% for 1 minute after corneal incision (...

spectrophotometric and electrochemical studies were successfully used in quantitative analysis of amitriptyline hydrochloride (ath) and nortriptyline hydrochloride (nth). conductometric titration were carried out in equeous solution using iodide and dopamine and serotonine as titrant. two new methods using spectrophotometry are dascribed for the determination of (ath) and (nth) with potassium b...

Previous models for ocular accommodation have suggested a dual sympathetic/parasympathetic innervation to the ciliary muscle. Such models would predict that sympathomimetic drugs should change the resting point or dark focus of accommodation. The effect of an alpha-adrenergic agonist (10% phenylephrine hydrochloride) on accommodation was examined; the results show a decrease in the near point o...