The sympathetic nervous system (SNS) and the cardiac natriuretic peptide system (NPS) are fundamentally important neurohumoral systems for cardiovascular regulation. Their mutual interactions have been subject to numerous experimental and human studies. In the current manuscript, results from in vivo and in vitro studies will be reviewed with a focus on sympathetic outflow on the control of nat...

The Sympathetic Nervous System and the Regulation of Cerebral Blood Flow in Man • Pharmacological blockade of the a adrenergic system by 20 mg phentolamine I.V. was shown not to influence CBF in 14 patients with an intact cerebral autoregulation. If the autoregulation—tested with angiotensin—was impaired for some reason, CBF was found to follow proportionally the blood pressure changes provoked...

The Sympathetic Nervous System and the Regulation of Cerebral Blood Flow in Man • Pharmacological blockade of the a adrenergic system by 20 mg phentolamine I.V. was shown not to influence CBF in 14 patients with an intact cerebral autoregulation. If the autoregulation—tested with angiotensin—was impaired for some reason, CBF was found to follow proportionally the blood pressure changes provoked...

The Sympathetic Nervous System and the Regulation of Cerebral Blood Flow in Man • Pharmacological blockade of the a adrenergic system by 20 mg phentolamine I.V. was shown not to influence CBF in 14 patients with an intact cerebral autoregulation. If the autoregulation—tested with angiotensin—was impaired for some reason, CBF was found to follow proportionally the blood pressure changes provoked...

Although considerable evidence suggests that the vestibular system regulates sympathetic outflow during movement and changes in posture, little is known about relative vestibular influences on activity of different sympathetic nerves and sympathetic efferents with different functions. In the present study, we demonstrated that electrical stimulation of the vestibular nerve in the cat elicited r...

Cardiac myocytes and the coronary circulation are innervated by both sympathetic and parasympathetic fibres which constitute the autonomic nervous system. 2 The autonomic outflow is controlled by regulatory centres in the midbrain, hypothalamus, pons, and medulla which integrate inputs from other brain areas as well as afferent stimuli from the periphery. The efferent signals follow descending ...

Results from animal experimentation suggest a 2-way interaction between leptin and the sympathetic nervous system, with leptin causing sympathetic activation and conversely, with the sympathetic system exercising regulatory feedback inhibition over leptin release. We have now tested this hypothesis in humans. In the absence of results from leptin infusions, to test for sympathetic stimulation o...

OBJECTIVE To investigate the effects of moderate-intensity exercise on the sympathetic nervous system in male smokers. METHODS Twenty-eight men (14 smokers and 14 non-smokers, ages 21-46 y) were recruited. The activity of the autonomic nervous system was measured by power spectral analysis of heart rate variability. Spectral power in the frequency domain was quantified by integrating the area...

Recent studies suggest that activation of the sympathetic nervous system either directly or indirectly influences cerebrovascular tone in humans even within the autoregulatory range. In 6 healthy subjects (aged 29+/-4 years), we used transcranial Doppler sonography to determine cerebral blood flow velocity during sympathetic activation elicited through head-up tilt (HUT) and sympathetic deactiv...

Insulin resistance and hyperinsulinemia may contribute to the development of arterial hypertension. Although insulin may elevate arterial pressure, in part, through activation of the sympathetic nervous system, the sites and mechanisms of insulin-induced sympathetic excitation remain uncertain. While sympathoexcitation during insulin may be mediated by the baroreflex, or by modulation of norepi...