Regional spinal cord blood flow in primates

1976 ◽  
Vol 45 (6) ◽  
pp. 647-659 ◽  
Author(s):  
Alan N. Sandler ◽  
Charles H. Tator
Keyword(s):  
Spinal Cord ◽  
Blood Flow ◽  
Cord Blood ◽  
Gray Matter ◽  
Mean Value ◽  
Spinal Cord Blood Flow ◽  
Thoracic Spinal Cord ◽  
Content Type ◽  
Arterial Blood ◽  
Thoracic Spinal

✓ Spinal cord blood flow (SCBF) was measured in the primate thoracic spinal cord using the 14C-antipyrine autoradiographic technique that allowed clear differentiation between white and gray matter blood flow. Individual SCBF values were obtained for 0.1-sq mm areas of the thoracic cord cross section. White matter blood flow was homogeneous throughout with a mean value of 10.3 ± 0.2 ml/100 gm/min. Graymatter flow was more variable with lower values in the dorsal horns and higher values in the central gray and anterior horns. Mean gray-matter flow was 57.6 ± 2.3 ml/100 gm/min. Arterial pO2 was 123 ± 2 torr, pCO2 was 40.2 ± 0.5 torr and pH was 7.327 ± 0.010. Mean arterial blood pressure was 113 ± 3 mm Hg and core temperature was 36.4° ± 0.1° C.

Effect of aminophylline and isoproterenol on spinal cord blood flow after impact injury

1980 ◽  
Vol 53 (3) ◽  
pp. 385-390 ◽  
Author(s):  
Diana Dow-Edwards ◽  
Vincent DeCrescito ◽  
John J. Tomasula ◽  
Eugene S. Flamm
Keyword(s):  
Spinal Cord ◽  
Blood Flow ◽  
White Matter ◽  
Cord Blood ◽  
Gray Matter ◽  
Adenosine Monophosphate ◽  
Spinal Cord Blood Flow ◽  
Content Type ◽  
Cord Injury ◽  
Matter Flow

✓ A study of the effects of spinal cord injury upon spinal cord blood flow was carried out in cats. A 400 gm-cm impact produced an overall reduction in spinal cord blood flow of 24% in the white matter and 30% in the gray matter, as determined by 14C-antipyrine autoradiography. At the level of the injury, white-matter flow was 8.1 ml/100 gm/min, a reduction of 49%, and in the gray matter, 12.5 ml/100 gm/min, a reduction of 76%. Treatment with aminophylline and isoproterenol improved the overall blood flow in the spinal cord. At the level of the injury, white-matter flow after this treatment was no longer significantly different from control values. The gray-matter flow remained decreased to 26.2 ml/100 gm/min, a reduction of only 47%. It is proposed that aminophylline and isoproterenol may increase cyclic adenosine monophosphate (AMP) and prevent platelet aggregation along the endothelial surfaces of the microcirculation, and may thereby help to maintain improved perfusion of the injured spinal cord.

Regional spinal cord blood flow in rats after severe cord trauma

1978 ◽  
Vol 49 (6) ◽  
pp. 844-853 ◽  
Author(s):  
Alex S. Rivlin ◽  
Charles H. Tator
Keyword(s):  
Spinal Cord ◽  
Blood Flow ◽  
Cord Blood ◽  
Gray Matter ◽  
Albino Rats ◽  
Compression Injury ◽  
Spinal Cord Blood Flow ◽  
Compression Technique ◽  
Content Type ◽  
Cord Injury

✓ Spinal cord blood flow (SCBF) was measured in 12 albino rats following acute cord injury produced by the extradural clip compression technique. Severe injury was produced with the clip compressing the cord with a force of 180 gm for 5 minutes, an injury previously shown to produce a severe functional deficit. Regional SCBF was measured 15 minutes, 2 hours, and 24 hours after injury by the 14C-antipyrine autoradiographic technique and a scanning microscope photometer. At 15 minutes and 2 hours, white and gray matter blood flow was severely diminished, and, at 24 hours, there was only minimal improvement. Focal decreases in blood flow were seen in white and gray matter for a considerable distance proximal and distal to the site of cord trauma. Thus, it has been confirmed in this model that severe cord compression injury produces severe posttraumatic ischemia in the cord which lasts for at least 24 hours.

Effect of acute spinal cord compression injury on regional spinal cord blood flow in primates

1976 ◽  
Vol 45 (6) ◽  
pp. 660-676 ◽  
Author(s):  
Alan N. Sandler ◽  
Charles H. Tator
Keyword(s):  
Spinal Cord ◽  
Blood Flow ◽  
White Matter ◽  
Cord Blood ◽  
Gray Matter ◽  
Regional Blood Flow ◽  
Compression Injury ◽  
Spinal Cord Blood Flow ◽  
Content Type ◽  
Cord Injury

✓ Spinal cord blood flow (SCBF) was measured in 24 rhesus monkeys after injury to the cord produced by the inflatable circumferential extradural cuff technique. Measurement of regional blood flow in the white and gray matter of the cord in areas of 0.1 sq mm was achieved with the 14C-antipyrine autoradiographic technique and a scanning microscope photometer. After moderate cord injury (400 mm Hg pressure in the cuff maintained for 5 minutes), which produced paraplegia in 50% of animals and moderate to severe paresis in the other 50%, mean white matter SCBF was significantly decreased for up to 1 hour. White matter blood flow then rose to normal levels by 6 hours posttrauma and was significantly increased by 24 hours posttrauma. Gray matter SCBF was significantly decreased for the entire 24-hour period post-trauma. After severe cord injury (150 mm Hg pressure in the cuff maintained for 3 hours), which produced total paraplegia in almost all animals, SCBF in white and gray matter was reduced to extremely low levels for 24 hours posttrauma. In addition, focal decreases in SCBF were seen in white and gray matter for considerable distances proximal and distal to the injury site. It is concluded that acute compression injury of the spinal cord is associated with long-lasting ischemia in the cord that increases in severity with the degree of injury.

Effects of anesthesia and laminectomy on regional spinal cord blood flow in conscious sheep

1981 ◽  
Vol 54 (5) ◽  
pp. 620-626 ◽  
Author(s):  
J. Robert S. Hales ◽  
John D. Yeo ◽  
Stefanie Stabback ◽  
Alan A. Fawcett ◽  
Raymond Kearns
Keyword(s):  
Spinal Cord ◽  
Blood Flow ◽  
White Matter ◽  
Cord Blood ◽  
Gray Matter ◽  
Sodium Pentobarbital ◽  
Spinal Cord Blood Flow ◽  
Regional Variations ◽  
Content Type ◽  
Conscious Sheep

✓ Blood flow for the whole spinal cord (SCBF), central cord (largely gray matter), and peripheral cord (largely white matter) has been measured at all segmental levels using radioactive microspheres in conscious sheep. Whole SCBF was greatest in the lower cervical and lumbar enlargements and least in the upper cervical and thoracic regions. This was attributable partly to regional variations in gray-matter blood flow but principally to regional variations in the proportion of gray and white matter present. Whole SCBF for the total cord was 14.5 ± 0.8 ml/100 gm/min, central cord flow was 40.6 ± 3.5 ml/100 gm/min, and peripheral cord flow was 9.7 ± 1.9 ml/100 gm/min. Blood flow was not affected by sodium pentobarbital provided the level of anesthesia, arterial pressure, and blood gases was carefully regulated. Laminectomy usually resulted in a marked increase in central cord blood flow at the site of cord exposure, lasting about 90 minutes; this increase was not necessarily reflected in whole SCBF because of the absence of any change in blood flow in the relatively large proportion of peripheral cord. This effect of laminectomy could adversely influence results obtained from studies using invasive techniques to measure SCBF.

The effects of beta adrenergic blockade on spinal cord autoregulation in the monkey

1977 ◽  
Vol 47 (1) ◽  
pp. 57-63 ◽  
Author(s):  
Arthur I. Kobrine ◽  
Delbert E. Evans ◽  
Hugo V. Rizzoli
Keyword(s):  
Spinal Cord ◽  
Blood Flow ◽  
Cord Blood ◽  
Adrenergic Blockade ◽  
Spinal Cord Blood Flow ◽  
Beta Adrenergic ◽  
Content Type ◽  
Arterial Blood ◽  
Wide Range ◽  
Adrenergic Blocker

✓ Blood flow in the spinal cord was measured in a group of monkeys over a wide range of artificially varied blood pressures after the administration of propranolol, a beta adrenergic blocker. Spinal cord blood flow was found to be constant and in the normal range between a mean system arterial blood pressure of 50 to 150 mm Hg. From 150 to 180 mm Hg spinal cord blood flow decreased. There was no breakthrough of autoregulation, previously seen in the untreated animal. It is suggested, therefore, that the previously observed breakthrough of autoregulation is a beta adrenergic-mediated phenomenon.

The effect of hypothermia on regional spinal cord blood flow in rats

1989 ◽  
Vol 70 (5) ◽  
pp. 780-784 ◽  
Author(s):  
Toshihisa Sakamoto ◽  
William W. Monafo
Keyword(s):  
Spinal Cord ◽  
Blood Flow ◽  
Cord Blood ◽  
Spinal Cord Ischemia ◽  
Control Level ◽  
Normal Group ◽  
Spinal Cord Blood Flow ◽  
Content Type ◽  
Arterial Blood ◽  
Anesthetized Rats

✓ Spinal cord ischemia may accompany surgical procedures on the aorta or vertebral column. Regional spinal cord blood flow (SCBF) was measured at five vertebral levels in the spinal cords of pentobarbital-anesthetized rats based on the distribution of intravenously injected carbon-14-labeled butanol. In seven normal rats, mean SCBF (± standard error of the mean) ranged from 52.7 ± 5.4 to 68.5 ± 4.9 ml ⋅ min−1 ⋅ 100 gm−1 (depending on the level, being lowest at the thoracic levels) and mean arterial blood pressure (MABP) was 126 mm Hg. Corporal hypothermia (mean rectal temperature 28.1° ± 0.6°C) was induced by cold exposure in seven other rats, and SCBF, measured immediately thereafter, was significantly elevated at all five levels by 52% to 69% compared to the normal group. However, MABP was elevated in the hypothermic group to 165 ± 4 mm Hg (p < 0.0001). Therefore, in seven additional hypothermic rats, MABP was maintained at the control level by withdrawal of arterial blood as necessary. In these animals, SCBF at all levels was still significantly elevated compared with the normal group and the values were nearly identical to those measured in the hypertensive hypothermic rats. It was concluded that hemodynamic autoregulation of SCBF is impaired in the presence of moderate systemic hypothermia in pentobarbital-anesthetized rats.

Spinal cord blood flow as affected by changes in systemic arterial blood pressure

1976 ◽  
Vol 44 (1) ◽  
pp. 12-15 ◽  
Author(s):  
Arthur I. Kobrine ◽  
Thomas F. Doyle ◽  
Hugo V. Rizzoli
Keyword(s):  
Spinal Cord ◽  
Blood Flow ◽  
Cord Blood ◽  
Spinal Cord Blood Flow ◽  
Content Type ◽  
Arterial Blood ◽  
Wide Range ◽  
Blood Pressures ◽  
Infusion Of Norepinephrine ◽  
Hydrogen Clearance

✓ The authors used the hydrogen clearance method to measure focal spinal cord blood flow (SCBF) in the rhesus monkey over a wide range of mean arterial blood pressures (MAP) in an attempt to test the hypothesis of autoregulation. The MAP was either lowered by bleeding or raised by the intravenous infusion of norepinephrine or angiotensin. The SCBF remained constant and in the normal range with an MAP of 50 to 135 mm Hg, indicating the presence of autoregulation. Below 50 mm Hg, SCBF fell passively with further decreases in MAP. At MAP values above 135 mm Hg, vasodilatation occurred which resulted in a breakthrough of autoregulation and marked increases in SCBF with further increases in the MAP.

Cardiorespiratory and Spinal Cord Blood Flow Effects of Intrathecal Neostigmine Methylsulfate, Clonidine, and Their Combination in Sheep 

1995 ◽  
Vol 82 (2) ◽  
pp. 428-435 ◽  
Author(s):  
David D. Hood ◽  
James C. Eisenach ◽  
Chuanyao Tong ◽  
Ellen Tommasi ◽  
Tony L. Yaksh
Keyword(s):  
Spinal Cord ◽  
Clinical Trials ◽  
Blood Flow ◽  
Cord Blood ◽  
Intrathecal Injection ◽  
Central Venous ◽  
Spinal Cord Blood Flow ◽  
Arterial Blood ◽  
Thoracic Spinal ◽  
Flow Effects

Background Intrathecal neostigmine may produce analgesia by itself and may enhance analgesia from spinal clonidine. Before clinical trials, the spinal cord blood flow effects of these drugs alone and in combination should be examined in animals. Methods Conscious, nonpregnant ewes with indwelling vascular and thoracic spinal catheters received intrathecal injection of 0.2 or 2 mg neostigmine, 0.2 mg clonidine, or 2 mg neostigmine plus 0.2 mg clonidine. Mean systemic and pulmonary arterial and central venous pressures, heart rate, and cardiac output were monitored, arterial blood was sampled for blood gas tensions and pH, and spinal cord blood flow was determined by colored microsphere injection before and at 15, 60, and 240 min after spinal study drug injection. Results Neostigmine alone did not affect cardiorespiratory variables or spinal cord blood flow. Intrathecal clonidine alone decreased systemic arterial and central venous pressures, whereas these effects were not observed with addition of neostigmine. Clonidine or neostigmine alone or the combination of clonidine and neostigmine did not affect spinal cord blood flow. Conclusions Intrathecal neostigmine alone or in combination with clonidine does not reduce spinal cord blood flow, an important preclinical toxicity issue. These results provide additional support for initial clinical trials of intrathecal neostigmine for analgesia.

Effects of laminectomy on spinal cord blood flow

1978 ◽  
Vol 48 (2) ◽  
pp. 232-238 ◽  
Author(s):  
Douglas K. Anderson ◽  
Gregory R. Nicolosi ◽  
Eugene D. Means ◽  
L. Edward Hartley
Keyword(s):  
Spinal Cord ◽  
Blood Flow ◽  
Cord Blood ◽  
Reference Sample ◽  
Significant Decline ◽  
Entire Length ◽  
Spinal Cord Blood Flow ◽  
Content Type ◽  
Sample Method ◽  
Fine Print

✓ The effect of a one-segment (L-2) laminectomy on spinal cord blood flow (SCBF) was determined by the reference sample method using isotope-labeled microspheres. The SCBF was measured before laminectomy (control) and at 15 minutes postlaminectomy with the dura exposed (Series 1), 1 hour postlaminectomy with the laminectomy site closed (Series 2), 24 hours postlaminectomy with the laminectomy site closed (Series 3), and 24 hours postlaminectomy with the dura exposed (Series 4). With the laminectomy site open, SCBF was significantly depressed (22% to 45%) along the entire length of the spinal cord at 15 minutes postlaminectomy. At 1 hour postlaminectomy (with the laminectomy site closed), SCBF approached control values, although areas with significantly lowered flow were still observed in all portions of the spinal cord. By 24 hours postlaminectomy, SCBF had returned to prelaminectomy levels. However, if within 1 hour preceding the 24-hour SCBF measurement, the laminectomy site was reopened, SCBF tended to fall at and caudad to the laminectomy site. These data indicate that laminectomy can cause a significant decline in SCBF. At the present time, the mechanism(s) for this laminectomy-induced depression of SCBF are unknown, although a temperature-induced vasoconstriction is suspected.

Sign in / Sign up

Export Citation Format

Share Document