Aging is associated with increased retrograde and oscillatory shear in peripheral conduit arteries of humans. Although the mechanisms responsible for these age-related changes are not completely understood, augmented downstream α-adrenergic tone likely plays a significant role in this phenomenon. Therefore, in protocol 1, brachial artery diameter and blood velocity were measured via Doppler ult...

The involvement of the antilipolytic alpha(2)-adrenergic pathway and the specific role of epinephrine in the control of lipolysis during exercise in adipose tissue (AT) were investigated in healthy male subjects (age: 24.1 +/- 2.2 yr; body mass index: 23.0 +/- 1.6). An in vitro study carried out on isolated adipocytes showed that the weak lipolytic effect of epinephrine was potentiated after bl...

Na-Ca exchange is proposed to be an important regulator of myoplasmic intracellular Ca concentration ([Ca]|) and contraction in vascular smooth muscle. We investigated the role of Na-Ca exchange in regulating [Ca], in swine carotid arterial tissues that were loaded with aequorin to allow simultaneous measurement of [Ca], and force. Reversal of Na-Ca exchange, by reduction of extracellular Na co...

BACKGROUND Mental stress reliably induces increases in salivary alpha amylase (sAA), a suggested surrogate marker for sympathetic nervous system (SNS) reactivity. While stress-induced sAA increases correlate with norepinephrine (NE) secretion, a potential mediating role of noradrenergic mechanisms remains unclear. In this study, we investigated for the first time in humans whether a NE-stress-r...

External urethral sphincter electromyography (EMG) during bladder filling was quantitatively analysed using automatic decomposition electromyography (ADEMG). These include 7 normal volunteers, 7 patients with outlet obstruction, 9 with sphincter dyssynergia, and 7 with pelvic nerve injury (PNI). Recruited number of participated motor unit action potentials (MUPs) at maximum bladder filling was ...

Intravenous infusion of 1· 5 mg adrenaline over 30 min into adult Merino wethers (50 kg body weight), increased glucose, lactate, and free fatty acid (FFA) concentrations in plasma much more than did a single rapid intravenous injection of the same amount. There was no increase in plasma insulin concentration during adrenaline infusion or after adrenaline injection. There was a logarithmic rela...

Background. Although a-adrenergic receptors are present in both normal and failing human left ventricular myocardium and mediate a positive inotropic effect in several other species, it is not known whether stimulation of myocardial ca-adrenergic receptors exerts a positive inotropic effect or contributes to basal contractile state in vivo in humans. Methods and Results. We studied 15 patients ...

Phenylephrine is generally regarded as a "pure" alpha(1)-agonist. However, after treatment of the forearm with the alpha-adrenergic-blocking drug phentolamine, brachial artery infusion of phenylephrine can cause transient forearm vasodilation. To determine whether this response was beta-receptor mediated, phenylephrine, phentolamine, and propranolol were infused into the brachial arteries of si...

We determined the effect of alpha-adrenergic receptor stimulation on cyclic adenosine monophosphate (cyclic AMP) concentrations in isolated myocytes derived from adult rat hearts and in isolated perfused rat hearts. Activation of alpha-adrenergic receptors with either phenylephrine (10(-8) M to 10(-6) M) or epinephrine (10(-8) M to 10(-6) M) plus propranolol (10(-6) M) resulted in a reduction i...

teucrium polium is used for treatment of visceral pain in iranian folkloric medicine. in this studyantinociceptive mechanisms of t. polium hydroethanolic extract were examined by acetic acid-inducedwrithing test as a model of visceral pain in male nmri mice. to reveal the antinociceptive mechanisms ofthe extract, we examined the effects of opioidergic, serotonergic, adrenergic and histaminergic...