We studied the effects of intense sympathetic stimulation on the chronotropic responses of the heart to subsequent test stimulations of the cardiac autonomic nerves in dogs anesthetized with a-chloralose. Such intense sympathetic stimulations (which we refer to as "release stimulations") are known to release neuropeptide Y as well as norepinephrine. The changes in cardiac cycle length evoked by...

BACKGROUND Sympathetic excitation characterizes heart failure, but the underlying mechanisms remain unknown. Abnormal baroreflex restraint of sympathetic neural outflow has been proposed, since baroreflexes are known to be abnormal in heart failure. The purpose of this study was to determine if sympathetic activation in humans with heart failure is limited to regions governed by the baroreflexe...

SINCE the sympathetic nervous system has such a central place in homeostasis in general, and in circulatory adaptation in particular, it is paradoxical that so little is known about the possible contribution of disturbed sympathetic nervous function to the development of human diseases. Clinical tests of sympathetic nervous system activity have, by and large, been routinely applied in one setti...

Stellate ganglion blockade (SGB) with a local anesthetic increases muscle sympathetic nerve activity in the tibial nerve in humans. However, whether this sympathetic excitation in the tibial nerve is due to a sympathetic blockade in the neck itself, or due to infiltration of a local anesthetic to adjacent nerves including the vagus nerve remains unknown. To rule out one mechanism, we examined t...

Obesity is recognized as a major, worldwide, health problem. Excess weight greatly increases the risk for cardiovascular diseases, diabetes and renal diseases. The present study was conducted in Department of Physiology, Index Medical College, Indore. 50 obese (25 male 25 female) non-obese were included. Sympathetic tests performed on both groups. All data are expressed mean± standard deviation...

Postnatal homozygous neurotrophin-3 mutant mice display a loss of about half the sympathetic superior cervical ganglion (SCG) neurons (Ernfors, P., Lee, K.-F., Kucera, J. and Jaenisch, R. (1994a) Cell 77, 503-512; Farinas, I., Jones, K. R., Backus, C., Wang, X. Y. and Reichardt, L. F. (1994) Nature 369, 658-661). We found that this loss is caused by excessive apoptosis of sympathetic neuroblast...