RELEASE OF ENDOGENOUS OPIOIDS FROM SPINAL CORD IN VIVO FOLLOWING SCIATIC NERVE STIMULATION

Author(s):  
K. Jhamandas ◽  
T.L. Yaksh ◽  
L. Bergstrom ◽  
J.-Y. Wang ◽  
L. Terenius
1986 ◽  
Vol 240 (2) ◽  
pp. 395-401 ◽  
Author(s):  
R A Challiss ◽  
D J Hayes ◽  
G K Radda

Muscle bloodflow and the rate of glucose uptake and phosphorylation were measured in vivo in rats 7 days after unilateral femoral artery ligation and section. Bloodflow was determined by using radiolabelled microspheres. At rest, bloodflow to the gastrocnemius, plantaris and soleus muscles of the ligated limb was similar to their respective mean contralateral control values; however, bilateral sciatic nerve stimulation at 1 Hz caused a less pronounced hyperaemic response in the muscles of the ligated limb, being 59, 63 and 49% of their mean control values in the gastrocnemius, plantaris and soleus muscles respectively. The rate of glucose utilization was determined by using the 2-deoxy[3H]glucose method [Ferré, Leturque, Burnol, Penicaud & Girard (1985) Biochem. J. 228, 103-110]. At rest, the rate of glucose uptake and phosphorylation was statistically significantly increased in the gastrocnemius and soleus muscles of the ligated limb, being 126 and 140% of the mean control values respectively. Bilateral sciatic nerve stimulation at 1 Hz caused a 3-5-fold increase in the rate of glucose utilization by the ligated and contralateral control limbs; furthermore, the rate of glucose utilization was significantly increased in the muscles of the ligated limb, being 140, 129 and 207% of their mean control values respectively. For the range of bloodflow to normally perfused skeletal muscle at rest or during isometric contraction determined in the present study, a linear correlation between the rate of glucose utilization and bloodflow can be demonstrated. Applying similar methods of regression analysis to glucose utilization and bloodflow to muscles of the ligated limb reveals a similar linear correlation. However, the rate of glucose utilization at a given bloodflow is increased in muscles of the ligated limb, indicating an adaptation of skeletal muscle to hypoperfusion.


1978 ◽  
Vol 38 (3) ◽  
pp. 435-439 ◽  
Author(s):  
Arthur I. Kobrine ◽  
Delbert E. Evans ◽  
Hugo V. Rizzoli

2008 ◽  
Vol 119 (5) ◽  
pp. 1111-1118 ◽  
Author(s):  
Shoji Tomizawa ◽  
Shigenori Kawabata ◽  
Hiromichi Komori ◽  
Yuko Hoshino Fukuoka ◽  
Kenichi Shinomiya

1975 ◽  
Vol 43 (3) ◽  
pp. 329-336 ◽  
Author(s):  
Robert J. Sarnowski ◽  
Roger Q. Cracco ◽  
Harold B. Vogel ◽  
Fred Mount

✓ Summated evoked potentials to sciatic nerve stimulation were recorded from surface electrodes placed over the spine of cats. The response progressively increased in latency rostrally. It was largest and most complex in configuration in leads placed over the caudal spinal cord where sciatic nerve roots enter and begin to ascend the cord. The conduction velocity of the response was about 90 m/sec from rostral sacral to cervical regions. A comparison of surface-recorded evoked responses to stimulation of the sural nerve, the nerve to the medial head of the gastrocnemius muscle and the sciatic nerve suggest that the peripheral nerve fibers that mediate the response to sciatic nerve stimulation are primarily muscle nerve afferents. In surface, lamina, and durai recordings made over similar segmental levels, the response to sciatic nerve stimulation progressively increased in amplitude, duration, and wave form complexity from surface to depth. Failure of transmission across complete cord transections was demonstrated. Results in preparations with partial cord sections suggest that the surface-recorded response is mediated by multiple spinal cord afferent pathways which are situated primarily ipsilateral to the stimulated peripheral nerve. The data indicate that summated evoked responses arising in spinal cord afferent pathways can be recorded from surface-recording electrodes in cats. They suggest that this animal model may prove useful in the study of certain aspects of spinal cord pathology.


Life Sciences ◽  
1983 ◽  
Vol 33 ◽  
pp. 17-20 ◽  
Author(s):  
Fred Nyberg ◽  
Tony L. Yaksh ◽  
Lars Terenius

1989 ◽  
Vol 71 (5) ◽  
pp. 747-753 ◽  
Author(s):  
B. Barry Chehrazi ◽  
Oscar Scremin ◽  
Emilio E. Decima

✓ Forty-two cats were subjected to decerebration, thoracic and lumbar laminectomies, and isolation of the sciatic nerves. Spinal evoked potentials in response to bilateral sciatic nerve stimulation were recorded at L-3, and the spinal cord blood flow (SCBF) was measured by the hydrogen clearance technique. Thoracic cordotomy did not alter the lumbar SCBF or the central conduction time as determined by spinal evoked potentials. Thoracic cordotomy significantly lowered the lumbar spinal cord injury threshold. Continuous sciatic nerve stimulation increased the lumbar SCBF in normal and traumatized animals; however, it did not affect the spinal cord injury threshold as measured by recovery of the spinal evoked potentials. It appears that rostral spinal cord integrity is far more significant in recovery from spinal cord injury than the maintenance of regional SCBF.


Sign in / Sign up

Export Citation Format

Share Document