|
|
||||||||
ARTICLES
To determine whether norepinephrine could subserve a hormonal as well as a neurotransmitter function, norepinephrine was infused for 60 min into each of five normal young men in doses of 0.1, 0.5, 1.0, 2.5, and 5.0 microgram/min. After infusion, the plasma norepinephrine concentration fell with a mean (+/-SD) half-time of 2.4 +/- 0.7 min. The mean (+/-SD) norepinephrine metabolic clearance rate was 3,070 +/- 200 ml/min. The calculated basal plasma norepinephrine production rate was 0.7 microgram/min. The blood pressure and circulating glycerol, acetoacetate, beta-hydroxybutyrate, and glucose (increased) and the heart rate and circulating insulin, lactate, pyruvate, and alanine (decreased) exhibited highly significant parabolic relationships with the steady-state plasma norepinephrine concentrations. However, norepinephrine levels in excess of 1,800 pg/ml were required to produce hemodynamic and/or metabolic effects. Thus, under usual conditions, the biologic actions of norepinephrine can be attributed only to its sympathetic neurotransmitter function. Plasma norepinephrine concentrations do at times exceed 1,800 pg/ml during exercise and during major acute illness. Thus, under conditions of stress, norepinephrine may subserve a hormonal, as well as a neurotransmitter, function.
This article has been cited by other articles:
![]() |
M. P. Tulppo, H. V. Huikuri, E. Tutungi, D. S. Kimmerly, A. W. Gelb, R. L. Hughson, T. H. Makikallio, and J. Kevin Shoemaker Feedback effects of circulating norepinephrine on sympathetic outflow in healthy subjects Am J Physiol Heart Circ Physiol, February 1, 2005; 288(2): H710 - H715. [Abstract] [Full Text] [PDF] |
||||
![]() |
B. Raju and P. E. Cryer Mechanism, temporal patterns, and magnitudes of the metabolic responses to the KATP channel agonist diazoxide Am J Physiol Endocrinol Metab, January 1, 2005; 288(1): E80 - E85. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. A. DeRosa and P. E. Cryer Hypoglycemia and the sympathoadrenal system: neurogenic symptoms are largely the result of sympathetic neural, rather than adrenomedullary, activation Am J Physiol Endocrinol Metab, July 1, 2004; 287(1): E32 - E41. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |