Neurobehavioral protection by the neuronal calcium channel blocker Ziconotide in a model of traumatic diffuse brain injury in rats

2000 ◽  
Vol 93 (5) ◽  
pp. 821-828 ◽  
Author(s):  
Robert F. Berman ◽  
Bon H. Verweij ◽  
J. Paul Muizelaar
Keyword(s):  
Brain Injury ◽  
Calcium Channel ◽  
Cognitive Deficits ◽  
Channel Blocker ◽  
Neuroprotective Effects ◽  
Content Type ◽  
Diffuse Brain Injury ◽  
Severe Motor ◽  
Fine Print ◽  
Diffuse Brain

Object. Abnormal accumulation of intracellular calcium following traumatic brain injury (TBI) is thought to contribute to a cascade of cellular events that lead to neuropathological conditions. Therefore, the possibility that specific calcium channel antagonists might exert neuroprotective effects in TBI has been of interest. The focus of this study was to examine whether Ziconotide produces such neuroprotective effects.Methods. The authors report that the acceleration—deceleration model of TBI developed by Marmarou, et al., induces a long-lasting deficit of neuromotor and behavioral function. The voltage-sensitive calcium channel blocker Ziconotide (also known as SNX-111 and CI-1009) exerts neuroprotective effects in this model of diffuse brain injury (DBI) in rats. The dose and time of injection of Ziconotide chosen for the present study was based on the authors' previous biochemical studies of mitochondria. Rats were trained in a series of motor and memory tasks, following which they were subjected to DBI using the Marmarou, et al., model. At 3, 5, and 24 hours, all rats were injected with 2 mg/kg Ziconotide for a total cumulative dose of 6 mg/kg Ziconotide. Control brain-injured animals were injected with an equal volume of saline vehicle at each of these time points. The rats were tested for motor and cognitive performance at 1, 3, 7, 14, 21, 28, 35, and 42 days postinjury. Saline-treated rats displayed severe motor and cognitive deficits after DBI. Compared with saline-treated control animals, rats treated with Ziconotide displayed better motor performance during inclined plane, beam balance, and beam walk tests; improved memory while in the radial arm maze; and improved learning while in the Morris water maze.Conclusions. These results demonstrated that the acceleration—deceleration model, which had been developed by Marmarou, et al., induces severe motor and cognitive deficits. We also demonstrated that Ziconotide exhibits substantial neuroprotective activity in this model of TBI. Improvement was observed in both motor and cognitive tasks, even though treatment was not initiated until 3 hours after injury. These findings support the development of neuronal N-type calcium channel antagonists as useful therapeutic agents in the treatment of TBI.

Influence of oxygen therapy on glucose—lactate metabolism after diffuse brain injury

2004 ◽  
Vol 101 (2) ◽  
pp. 323-329 ◽  
Author(s):  
Michael Reinert ◽  
Benoit Schaller ◽  
Hans Rudolf Widmer ◽  
Rolf Seiler ◽  
Ross Bullock
Keyword(s):  
Brain Injury ◽  
Brain Tissue ◽  
Brain Metabolism ◽  
Arterial Line ◽  
Content Type ◽  
Diffuse Brain Injury ◽  
Lactate Levels ◽  
The Brain ◽  
Fine Print ◽  
Diffuse Brain

Object. Severe traumatic brain injury (TBI) imposes a huge metabolic load on brain tissue, which can be summarized initially as a state of hypermetabolism and hyperglycolysis. In experiments O2 consumption has been shown to increase early after trauma, especially in the presence of high lactate levels and forced O2 availability. In recent clinical studies the effect of increasing O2 availability on brain metabolism has been analyzed. By their nature, however, clinical trauma models suffer from a heterogeneous injury distribution. The aim of this study was to analyze, in a standardized diffuse brain injury model, the effect of increasing the fraction of inspired O2 on brain glucose and lactate levels, and to compare this effect with the metabolism of the noninjured sham-operated brain. Methods. A diffuse severe TBI model developed by Foda and Maramarou, et al., in which a 420-g weight is dropped from a height of 2 m was used in this study. Forty-one male Wistar rats each weighing approximately 300 g were included. Anesthesized rats were monitored by placing a femoral arterial line for blood pressure and blood was drawn for a blood gas analysis. Two time periods were defined: Period A was defined as preinjury and Period B as postinjury. During Period B two levels of fraction of inspired oxygen (FiO2) were studied: air (FiO2 0.21) and oxygen (FiO2 1). Four groups were studied including sham-operated animals: air-air-sham (AAS); air-O2-sham (AOS); air-air-trauma (AAT); and air-O2-trauma (AOT). In six rats the effect of increasing the FiO2 on serum glucose and lactate was analyzed. During Period B lactate values in the brain determined using microdialysis were significantly lower (p < 0.05) in the AOT group than in the AAT group and glucose values in the brain determined using microdialysis were significantly higher (p < 0.04). No differences were demonstrated in the other groups. Increasing the FiO2 had no significant effect on the serum levels of glucose and lactate. Conclusions. Increasing the FiO2 influences dialysate glucose and lactate levels in injured brain tissue. Using an FiO2 of 1 influences brain metabolism in such a way that lactate is significantly reduced and glucose significantly increased. No changes in dialysate glucose and lactate values were found in the noninjured brain.

A new model of diffuse brain injury in rats

1994 ◽  
Vol 80 (2) ◽  
pp. 301-313 ◽  
Author(s):  
Montasser A. Abd-Elfattah Foda ◽  
Anthony Marmarou
Keyword(s):  
Brain Injury ◽  
Brain Stem ◽  
Content Type ◽  
Diffuse Brain Injury ◽  
Weight Drop ◽  
Group 2 ◽  
The Brain ◽  
Fine Print ◽  
Diffuse Brain ◽  
Group 1

✓ A new model producing diffuse brain injury, without focal brain lesions, has been developed in rats. This has been achieved by allowing a weight of 450 gm to fall onto a metallic disc fixed to the intact skull of the animal which is supported by a foam bed. Two levels of injury were examined by adjusting the height of the falling weight to either 1 m or 2 m. Two groups of animals were studied. Group 1 animals were separated into three subgroups: 10 received a 1-m weight drop, 58 received a 2-m weight drop, and 13 served as controls; all were allowed to breathe spontaneously. Group 2 animals were separated into the same subgroups: four received a 1-m weight drop, six received a 2-m weight drop, and four served as controls; all of these were mechanically ventilated during the procedure. In Group 1, morphological studies using light and electron microscopy were performed at 1, 6, 24, or 72 hours, or 10 days after insult; all Group 2 rats were studied at 24 hours after injury. Results from Group 1 animals showed that no mortality occurred with the 1-m level injury, while 59% mortality was seen with the 2-m level injury. On the other hand, no mortality occurred in Group 2 animals regardless of the level of trauma induced. However, the morphological changes observed in both groups were similar. Gross pathological examination did not reveal any supratentorial focal brain lesion regardless of the severity of the trauma. Petechial hemorrhages were noticed in the brain stem at the 2-m level injury. Microscopically, the model produced a graded widespread injury of the neurons, axons, and microvasculature. Neuronal injury was mainly observed bilaterally in the cerebral cortex. Brain edema, in the form of pericapillary astrocytic swelling, was also noted in these areas of the cerebral cortex and in the brain stem. Most importantly, the trauma resulted in a massive diffuse axonal injury that primarily involved the corpus callosum, internal capsule, optic tracts, cerebral and cerebellar peduncles, and the long tracts in the brain stem. It is concluded that this model would be suitable for studying neuronal, axonal, and vascular changes associated with diffuse brain injury.

Evaluation of a novel calcium channel blocker, (S)-emopamil, on regional cerebral edema and neurobehavioral function after experimental brain injury

1992 ◽  
Vol 77 (4) ◽  
pp. 607-615 ◽  
Author(s):  
Koichi Okiyama ◽  
Douglas H. Smith ◽  
Mark J. Thomas ◽  
Tracy K. McIntosh
Keyword(s):  
Brain Injury ◽  
Calcium Channel ◽  
Calcium Channel Blocker ◽  
Motor Function ◽  
Cerebral Edema ◽  
Channel Blocker ◽  
Memory Function ◽  
Tissue Water ◽  
Content Type ◽  
Neurobehavioral Function

✓ The authors investigated the effects of a novel calcium channel blocker, (S)-emopamil, on cerebral edema and neurobehavioral and memory function following experimental fluid-percussion brain injury in the rat. Two independent experiments were performed to evaluate the effects of this compound on cardiovascular variables and postinjury cerebral edema (increases in tissue water content), and on cognitive deficits and neurological motor function following brain injury. Treatment with (S)-emopamil significantly reduced focal brain edema at 48 hours after brain injury. Profound memory dysfunction induced by brain injury was significantly attenuated following (S)-emopamil treatment. In addition, (S)-emopamil also attenuated the deficits in motor function that were observed over a 2-week period following brain injury. These results suggest that changes in calcium homeostasis may play an important role in the pathogenesis of trauma to the central nervous system and that the calcium channel blocker (S)-emopamil might be a useful compound for the treatment of traumatic brain injury.

scholarly journals Cognitive deficits develop 1 month after diffuse brain injury and are exaggerated by microglia-associated reactivity to peripheral immune challenge

2016 ◽  
Vol 54 ◽  
pp. 95-109 ◽  
Author(s):  
Megan M. Muccigrosso ◽  
Joni Ford ◽  
Brooke Benner ◽  
Daniel Moussa ◽  
Christopher Burnsides ◽  
...  
Keyword(s):  
Brain Injury ◽  
Cognitive Deficits ◽  
Immune Challenge ◽  
Diffuse Brain Injury ◽  
Diffuse Brain

Neuroprotective effects of citicoline on brain edema and blood—brain barrier breakdown after traumatic brain injury

2000 ◽  
Vol 92 (3) ◽  
pp. 448-452 ◽  
Author(s):  
Mustafa K. Başkaya ◽  
Aclan Doğan ◽  
A. Muralikrishna Rao ◽  
Robert J. Dempsey
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Brain Edema ◽  
Blood Brain Barrier ◽  
Brain Barrier ◽  
Blue Dye ◽  
Neuroprotective Effects ◽  
Content Type ◽  
Blood Brain ◽  
Fine Print

Object. Cytidine 5′-diphosphocholine (CDPC), or citicoline, is a naturally occurring endogenous compound that has been reported to provide neuroprotective effects after experimental cerebral ischemia. However, in no study has such protection been shown after traumatic brain injury (TBI). In this study the authors examined the effect of CDPC on secondary injury factors, brain edema and blood-brain barrier (BBB) breakdown, after TBI.Methods. After anesthesia had been induced in Sprague—Dawley rats by using 1.5% halothane, an experimental TBI was created using a controlled cortical impact (CCI) device with a velocity of 3 m/second, resulting in a 2-mm deformation. Four sham-operated control animals used for brain edema and BBB breakdown studies underwent the same surgical procedure, but received no injury. Brain edema was evaluated using the wet—dry method 24 hours postinjury, and BBB breakdown was evaluated by measuring Evans blue dye (EBD) extravasation with fluorescein 6 hours after TBI. The animals received intraperitoneal injections of CDPC (50, 100, or 400 mg/kg two times after TBI [eight–10 animals in each group]) or saline (eight animals) after TBI. Traumatic brain injury induced an increase in the percentage of water content and in EBD extravasation in the injured cortex and the ipsilateral hippocampus. No significant benefit from CDPC treatment was observed at a dose of 50 mg/kg. Cytidine 5′-diphosphocholine at a dose of 100 mg/kg attenuated EBD extravasation in both regions, although it reduced brain edema only in the injured cortex. In both regions, 400 mg/kg of CDPC significantly decreased brain edema and BBB breakdown.Conclusions. This is the first report in which dose-dependent neuroprotective effects of CDPC have been demonstrated in the injured cortex as well as in the hippocampus, a brain region known to be vulnerable to injury, after experimental TBI. The results of this study suggest that CDPC is an effective neuroprotective agent on secondary injuries that appear following TBI.

Significance of intracranial hypertension in severe head injury

1977 ◽  
Vol 47 (4) ◽  
pp. 503-516 ◽  
Author(s):  
J. Douglas Miller ◽  
Donald P. Becker ◽  
John D. Ward ◽  
Humbert G. Sullivan ◽  
William E. Adams ◽  
...  
Keyword(s):  
Brain Injury ◽  
Head Injury ◽  
Intracranial Hypertension ◽  
Severe Head Injury ◽  
Neurological Status ◽  
Content Type ◽  
Diffuse Brain Injury ◽  
Mass Lesions ◽  
Increased Icp ◽  
Diffuse Brain

✓ Measurements of intracranial pressure (ICP) were begun within hours of injury in 160 patients with severe brain trauma, and continued in the intensive care unit. Some degree of increased ICP (> 10 mm Hg) was present on admission in most cases (82%), and in all but two of the 62 patients with intracranial mass lesions requiring surgical decompression; ICP was over 20 mm Hg on admission in 44% of cases, and over 40 mm Hg in 10%. In patients with mass lesions only very high ICP (> 40 mm Hg) on admission was significantly associated with a poor neurological picture and outcome from injury, while in patients with diffuse brain injury any increase in ICP above 10 mm Hg was associated with a poorer neurological status and a worse outcome. Despite intensive measures aimed at prevention of intracranial hypertension, ICP rose over 20 mm Hg during the monitoring period in 64 of the 160 patients (40%). Postoperative increases in ICP over 20 mm Hg (mean) were seen in 52% of the patients who had had intracranial masses evacuated, and could not be controlled by therapy in half of these cases. Even in patients without mass lesions, ICP rose above 20 mm Hg in a third of the cases, despite artificial ventilation and steroid therapy. Of the 48 patients who died, severe intracranial hypertension was the primary cause of death in nearly half and even moderately increased ICP (> 20 mm Hg) was associated with higher morbidity in patients with mass lesions and those with diffuse brain injury. Measurement of ICP should be included in management of patients with severe head injury.

scholarly journals Nilvadipine, a New Calcium Channel Blocker, Reduces Ischemic Brain Injury in Rats

1991 ◽  
Vol 56 (4) ◽  
pp. 547-550
Author(s):  
Shoji Takakura ◽  
Teruo Susumu ◽  
Hisashi Satoh ◽  
Jo Mori ◽  
Akihiko Shiino ◽  
...  
Keyword(s):  
Brain Injury ◽  
Calcium Channel ◽  
Calcium Channel Blocker ◽  
Channel Blocker ◽  
Ischemic Brain Injury ◽  
Ischemic Brain

Flushing in relation to a possible rise in intracranial pressure: documentation of an unusual clinical sign

2000 ◽  
Vol 92 (6) ◽  
pp. 1040-1044 ◽  
Author(s):  
Gregory W. Hornig
Keyword(s):  
Traumatic Brain Injury ◽  
Brain Injury ◽  
Intracranial Pressure ◽  
Intraventricular Hemorrhage ◽  
Pneumococcal Meningitis ◽  
Clinical Importance ◽  
Neurological Deterioration ◽  
Content Type ◽  
Transient Nature ◽  
Fine Print

✓ This report documents clinical features in five children who developed transient reddening of the skin (epidermal flushing) in association with acute elevations in intracranial pressure (ICP). Four boys and one girl (ages 9–15 years) deteriorated acutely secondary to intracranial hypertension ranging from 30 to 80 mm Hg in the four documented cases. Two patients suffered from ventriculoperitoneal shunt malfunctions, one had diffuse cerebral edema secondary to traumatic brain injury, one was found to have pneumococcal meningitis and hydrocephalus, and one suffered an intraventricular hemorrhage and hydrocephalus intraoperatively. All patients were noted to have developed epidermal flushing involving either the upper chest, face, or arms during their period of neurological deterioration. The response was transient, typically lasting 5 to 15 minutes, and dissipated quickly. The flushing reaction is postulated to be a centrally mediated response to sudden elevations in ICP. Several potential mechanisms are discussed. Flushing has clinical importance because it may indicate significant elevations in ICP when it is associated with neurological deterioration. Because of its transient nature, the importance of epidermal flushing is often unrecognized; its presence confirms the need for urgent treatment.

The effects of methylprednisolone and the ganglioside GM1 on acute spinal cord injury in rats

1994 ◽  
Vol 80 (1) ◽  
pp. 97-111 ◽  
Author(s):  
Shlomo Constantini ◽  
Wise Young
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Body Weight Loss ◽  
Ganglioside Gm1 ◽  
Rat Spinal Cord ◽  
Neuroprotective Effects ◽  
Content Type ◽  
Human Spinal Cord ◽  
Cord Injury ◽  
Fine Print

✓ Recent clinical trials have reported that methylprednisolone sodium succinate (MP) or the monosialic ganglioside GM1 improves neurological recovery in human spinal cord injury. Because GM1 may have additive or synergistic effects when used with MP, the authors compared MP, GM1, and MP+GM1 treatments in a graded rat spinal cord contusion model. Spinal cord injury was caused by dropping a rod weighing 10 gm from a height of 1.25, 2.5, or 5.0 cm onto the rat spinal cord at T-10, which had been exposed via laminectomy. The lesion volumes were quantified from spinal cord Na and K shifts at 24 hours after injury and the results were verified histologically in separate experiments. A single dose of MP (30 mg/kg), given 5 minutes after injury, reduced 24-hour spinal cord lesion volumes by 56% (p = 0.0052), 28% (p = 0.0065), and 13% (p > 0.05) in the three injury-severity groups, respectively, compared to similarly injured control groups treated with vehicle only. Methylprednisolone also prevented injury-induced hyponatremia and increased body weight loss in the spine-injured rats. When used alone, GM1 (10 to 30 mg/kg) had little or no effect on any measured variable compared to vehicle controls; when given concomitantly with MP, GM1 blocked the neuroprotective effects of MP. At a dose of 3 mg/kg, GM1 partially prevented MP-induced reductions in lesion volumes, while 10 to 30 mg/kg of GM1 completely blocked these effects of MP. The effects of MP on injury-induced hyponatremia and body weight loss were also blocked by GM1. Thus, GM1 antagonized both central and peripheral effects of MP in spine-injured rats. Until this interaction is clarified, the authors recommend that MP and GM1 not be used concomitantly to treat acute human spinal cord injury. Because GM1 modulates protein kinase activity, protein kinases inhibit lipocortins, and lipocortins mediate anti-inflammatory effects of glucocorticoids, it is proposed that the neuroprotective effects of MP are partially due to anti-inflammatory effects and that GM1 antagonizes the effects of MP by inhibiting lipocortin. Possible beneficial effects of GM1 reported in central nervous system injury may be related to the effects on neural recovery rather than acute injury processes.

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