| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
1 Experimental Research Department and Institute of Human Physiology, and 2 Faculty of Medicine, Department of Anatomy, Histology, and Embriology, Semmelweis University, 1082 Budapest, Hungary
The aim of this study
was to quantitate the density of nerve terminals as well as their
synaptic vesicle population in the adventitia of saphenous (SV and SA)
and brachial veins and arteries (BV and BA) obtained from rats
maintained in a horizontal control or a tilted position. Adult animals
were kept individually in tubelike cages in a 45° head-up position.
After 2 wk, both tilted and control animals were anesthetized, and the
whole body was perfused with fixative solution at physiological
pressure. Vessels segments were then excised for electron microscopy
and immunohistochemistry. The nerve terminal density (NTD) of SA was
8.20 ± 1.46 nerve terminals/100 µm2 cross section
of adventitia and that of SV was 4.53 ± 0.61 nerve terminals/100
µm2 cross section of adventitia in control rats. Tilting
caused a significant increase in NTD of both SA (70%) and SV (52%).
The synaptic microvesicle density (SyVD) was larger in SA than SV in
control rats (30.48 ± 4.41 vs. 13.38 ± 2.61 synaptic
vesicles/10 terminal sections), but tilting resulted in more pronounced
changes in SyVD of SV (95%) than SA (54%). No significant changes in
NTD and SyVD of BA were found after tilt (
3.6% relative to 4.99 ± 0.33 compared with 0.4% relative to 24.89 ± 3.7, respectively). Whereas NTD of BV exhibited a tendency to increase
(3.73 ± 0.86 vs. 2.31 ± 0.29 nerve terminals/100
µm2 cross section of adventitia), SyVD did not
change significantly (18.96 ± 2.74 vs. 22.85 ± 3.17 synaptic vesicles/10 terminal sections). A large number of
nerve terminals of all vessels were tyrosine hydroxylase immunoreactive
(containing norepinephrine). These findings support the hypothesis that
long-term gravitational load causes adaptive morphological and
functional remodeling of sympathetic innervation in blood vessels of
the extremities.
innervation of extremity arteries; innervation of extremity veins; neural remodeling; tilting head up; vascular adaptation to gravity
This article has been cited by other articles:
|
|
 |
|
  H. Edgell, K. A. Zuj, D. K. Greaves, J. K. Shoemaker, M.-A. Custaud, P. Kerbeci, P. Arbeille, and R. L. Hughson WISE-2005: adrenergic responses of women following 56-days, 6{degrees} head-down bed rest with or without exercise countermeasures Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2007; 293(6): R2343 - R2352. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Lipp, P. Sandroni, J. E. Ahlskog, D. M. Maraganore, C. W. Shults, and P. A. Low Calf venous compliance in multiple system atrophy Am J Physiol Heart Circ Physiol, July 1, 2007; 293(1): H260 - H265. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Monos, M. Lorant, G. Dornyei, V. Berczi, and G. Nadasy Long-Term Adaptation Mechanisms in Extremity Veins Supporting Orthostatic Tolerance Physiology, October 1, 2003; 18(5): 210 - 214. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Hayashi, K. Mori, and H. Miyazaki Biomechanical response of femoral vein to chronic elevation of blood pressure in rabbits Am J Physiol Heart Circ Physiol, February 1, 2003; 284(2): H511 - H518. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |
