Effect of drugs on experimental brain edema in mice

1974 ◽  
Vol 41 (2) ◽  
pp. 193-199 ◽  
Author(s):  
Stanley R. Nelson

✓ Cold-induced hemorrhagic infarcts in mice caused a spreading decrease in tissue specific gravity around the lesion; the decrease in tissue density represents an increase in edema fluid. The maximum decrease in density in most brain areas had occurred by 6 hours. This time period was used to evaluate the effect of nine drugs on brain edema. Two agents increased edema formation: hexamethonium and meralluride. Metaraminol, cortisone, hydrocortisone, acetazolamide, and dextran did not significantly alter edema formation. Only in the phenoxybenzamine- and urea-treated mice was brain edema less than in the control mice.

2000 ◽  
Vol 92 (6) ◽  
pp. 1016-1022 ◽  
Author(s):  
Ya Hua ◽  
Guohua Xi ◽  
Richard F. Keep ◽  
Julian T. Hoff

Object. Brain edema formation following intracerebral hemorrhage (ICH) appears to be partly related to erythrocyte lysis and hemoglobin release. Erythrocyte lysis may be mediated by the complement cascade, which then triggers parenchymal injury. In this study the authors examine whether the complement cascade is activated after ICH and whether inhibition of complement attenuates brain edema around the hematoma.Methods. This study was divided into three parts. In the first part, 100 µl of autologous blood was infused into the rats' right basal ganglia, and the animals were killed at 24 and 72 hours after intracerebral infusion. Their brains were tested for complement factors C9, C3d, and clusterin (a naturally occurring complement inhibitor) by using immunohistochemical analysis. In the second part of the study, the rats were killed at 24 or 72 hours after injection of 100 µl of blood. The C9 and clusterin proteins were quantitated using Western blot analysis. In the third part, the rats received either 100 µl of blood or 100 µl of blood plus 10 µg of N-acetylheparin (a complement activation inhibitor). Then they were killed 24 or 72 hours later for measurement of brain water and ion contents. It was demonstrated on Western blot analysis that there had been a sixfold increase in C9 around the hematoma 24 hours after the infusion of 100 µl of autologous blood. Marked perihematomal C9 immunoreactivity was detected at 72 hours. Clusterin also increased after ICH and was expressed in neurons 72 hours later. The addition of N-acetylheparin significantly reduced brain edema formation in the ipsilateral basal ganglia at 24 hours (78.5 ± 0.5% compared with 81.6 ± 0.8% in control animals, p < 0.001) and at 72 hours (80.9 ± 2.2% compared with 83.6 ± 0.9% in control animals, p < 0.05) after ICH.Conclusions. It was found that ICH causes complement activation in the brain. Activation of complement and the formation of membrane attack complex contributes to brain edema formation after ICH. Blocking the complement cascade could be an important step in the therapy for ICH.


1971 ◽  
Vol 34 (4) ◽  
pp. 477-487 ◽  
Author(s):  
Robert E. Maxwell ◽  
Don M. Long ◽  
Lyle A. French

✓ Although the beneficial effects of glucosteroids on brain edema are well documented and generally accepted clinically, investigations into their effects on experimental brain edema have been somewhat contradictory. In this study brain edema was produced by local cortical freezing in animals pretreated with glucosteroids and in untreated animals. Gross estimation of edema, wet weight-dry weight determination, and mechanical planimetry of areas of extravasated dye indicated a statistically significant reduction in edema of both white and gray matter at 24, 48, and 72 hours. Gross estimation of edema indicated a persisting effect with resolution of edema at 5 days in treated animals and from 7 to 12 days in untreated animals. These studies substantiate initial investigations and indicate a primary reduction in brain edema by glucosteroids. At least one of the effects of the glucosteroids appears to be reduction of the abnormal vascular permeability causing brain edema.


2001 ◽  
Vol 95 (4) ◽  
pp. 680-686 ◽  
Author(s):  
Tetsuya Masada ◽  
Ya Hua ◽  
Guohua Xi ◽  
Guo-Yuan Yang ◽  
Julian T. Hoff ◽  
...  

Object. Adenovirus-mediated overexpression of interleukin-1 receptor antagonist (IL-1ra) attenuates the inflammatory reaction and brain injury that follows focal cerebral ischemia. Recently, an inflammatory reaction after intracerebral hemorrhage (ICH) was identified. In this study the authors examine the hypothesis that overexpression of IL-1ra reduces brain injury (specifically edema formation) after ICH. Methods. Adenoviruses expressing IL-1ra (Ad.RSVIL-1ra) or LacZ, a control protein (Ad.RSVlacZ), or saline were injected into the left lateral cerebral ventricle in rats. On the 5th day after virus injection, 100 µl of autologous blood or 5 U thrombin was infused into the right basal ganglia. Rats with ICH were killed 24 or 72 hours later for measurement of brain water and ion content. Thrombin-treated rats were killed 24 hours later for edema measurements and an assessment of polymorphonuclear leukocyte (PMNL) infiltration by myeloperoxidase (MPO) assay, as well as histological evaluation. Compared with saline-treated and Ad.RSVlacZ—transduced controls, Ad.RSVIL-1ra-transduced rats had significantly attenuated edema in the ipsilateral basal ganglia 3 days after ICH (81.5 ± 0.3% compared with 83.4 ± 0.4% and 83.3 ± 0.5% in control animals). Thrombin-induced brain edema was also reduced in Ad.RSVIL-1ra—treated rats (81.3 ± 0.4% compared with 83.2 ± 0.4% and 82.5 ± 0.4% in control rats). The reduction in thrombin-induced edema was associated with a reduction in PMNL infiltration into the basal ganglia, as assessed by MPO assay (49% reduction) and histological examination. Conclusions. Overexpression of IL-1ra by using an adenovirus vector attenuated brain edema formation and thrombin-induced intracerebral inflammation following ICH. The reduction in ICH-induced edema with IL-1ra may result from reduction of thrombin-induced brain inflammation.


1978 ◽  
Vol 49 (4) ◽  
pp. 530-537 ◽  
Author(s):  
Anthony Marmarou ◽  
Werner Poll ◽  
Kenneth Shulman ◽  
Hemmige Bhagavan

✓ A simple method was developed for the laboratory preparation of gradient columns of specific gravity used in measurement of brain-tissue water. By this automated technique, virtually linear and repeatable density gradients were obtained from which values of tissue specific gravity could be determined. The specific gravity of both solid and fresh cortex and white matter from adult cats was measured and converted to units of percent water per gram tissue using conversion factors derived for this purpose and applicable to studies of brain edema.


1995 ◽  
Vol 83 (6) ◽  
pp. 1045-1050 ◽  
Author(s):  
Kevin R. Lee ◽  
A. Lorris Betz ◽  
Richard F. Keep ◽  
Thomas L. Chenevert ◽  
Seoung Kim ◽  
...  

✓ Purified thrombin from an exogenous source is a hemostatic agent commonly used in neurosurgical procedures. The toxicity of thrombin in the brain, however, has not been examined. This study was performed to assess the effect of thrombin on brain parenchyma, using the formation of brain edema as an indicator of injury. Ten µl of test solution was infused stereotactically into the right basal ganglia of rats. The animals were sacrificed 24 hours later, and the extent of brain edema and ion content were measured. Concentrations of human thrombin as low as 1 U/µl resulted in a significant increase in brain water content. Rats receiving 10 U/µl had a mortality rate of 33% compared to no mortality in the groups receiving smaller doses. Thrombin-induced brain edema was inhibited by a specific and potent thrombin inhibitor, hirudin. A medical grade of bovine thrombin commonly used in surgery also caused brain edema when injected at a concentration of 2 U/µl. Edema formation was prevented by another highly specific thrombin inhibitor, Nα-(2-Naphthalenesulfonylglycyl)-4-dl-phenylalaninepiperidide (α-NAPAP). Thrombininduced brain edema was accompanied by increases in brain sodium and chloride contents and a decrease in brain potassium content. Changes in brain ions were inhibited by both hirudin and α-NAPAP, corresponding to the inhibition of brain water accumulation. This study shows that thrombin causes brain edema when infused into the brain at concentrations as low as 1 U/µl, an amount within the range of concentrations used for topical hemostasis in neurosurgery.


2004 ◽  
Vol 100 (3) ◽  
pp. 498-504 ◽  
Author(s):  
Joachim Oertel ◽  
Michael Robert Gaab ◽  
Dirk-Thomas Pillich ◽  
Henry W. S. Schroeder ◽  
Rolf Warzok ◽  
...  

Object. The waterjet method of dissection has been shown to enable the precise dissection of the parenchyma vessels while preserving blood in cadaveric pig brains. The waterjet device has also been applied clinically to treat various diseases and disorders without complications. Evidence still remains to be gathered as to how the instrument performs in reducing surgical trauma, intraoperative blood loss, and postsurgical brain edema. In the present study the authors investigate these parameters in a comparison between waterjet dissection and ultrasonic aspiration in the rabbit brain in vivo. Methods. Thirty-one rabbits received identical bilateral frontal corticotomies, which were created using the waterjet device or an ultrasonic aspirator. The animals were killed 1, 3, or 7 days, or 6 weeks after surgery and their brains were processed for immunohistological analysis. Blood vessel preservation, intraoperative hemorrhage, postsurgical brain edema, and posttraumatic microglial and astoglial reactions were evaluated. Only in animals subjected to waterjet dissection were preserved vessels observed within the corticotomies. In addition, less intraoperative bleeding occurred in animals in which the waterjet was used. The microglial reaction was significantly reduced by waterjet dissection compared with ultrasonic aspiration; however, no difference in edema formation or astrocytic reactivity was observed. Conclusions. These results demonstrate that waterjet dissection appears to be less traumatic than ultrasonic aspiration with respect to intraoperative hemorrhage and postoperative microglial reactivity in the rabbit model. Nevertheless, no difference in edema formation could be demonstrated. It remains to be proven that the observed differences are of clinical relevance.


1998 ◽  
Vol 89 (6) ◽  
pp. 991-996 ◽  
Author(s):  
Guohua Xi ◽  
Richard F. Keep ◽  
Julian T. Hoff

Object. The mechanisms of brain edema formation following spontaneous intracerebral hemorrhage (ICH) are not well understood. In previous studies, no significant edema formation has been found 24 hours after infusion of packed red blood cells (RBCs) into the brain of a rat or pig; however, there is evidence that hemoglobin can be neurotoxic. In this study, the authors reexamined the role of RBCs and hemoglobin in edema formation after ICH. Methods. The experiments involved infusion of whole blood, packed RBCs, lysed RBCs, rat hemoglobin, or thrombin into the right basal ganglia of Sprague—Dawley rats. The animals were killed at different time points and brain water and ion contents were measured. The results showed that lysed autologous erythrocytes, but not packed erythrocytes, produced marked brain edema 24 hours after infusion and that this edema formation could be mimicked by hemoglobin infusion. Although infusion of packed RBCs did not produce dramatic brain edema during the first 2 days, it did induce a marked increase in brain water content 3 days postinfusion. Edema formation following thrombin infusion peaked at 24 to 48 hours. This is earlier than the peak in edema formation that follows ICH, suggesting that there is a delayed, nonthrombin-mediated, edemogenic component of ICH. Conclusions. These results demonstrate that RBCs play a potentially important role in delayed edema development after ICH and that RBC lysis and hemoglobin toxicity may be useful targets for therapeutic intervention.


1996 ◽  
Vol 85 (1) ◽  
pp. 131-137 ◽  
Author(s):  
Zeev Feldman ◽  
Boris Gurevitch ◽  
Alan A. Artru ◽  
Arieh Oppenheim ◽  
Esther Shohami ◽  
...  

✓ Excitatory amino acids (EAA), mainly glutamate and aspartate, are released in excessive amounts from terminals of ischemic or traumatically injured neurons. These excessive levels of EAAs initiate a cascade of events believed to lead to secondary delayed damage to the surrounding brain. The N-methyl-d-aspartate receptor antagonists MK-801 and ketamine are reported to suppress excessive EAA release and to attenuate the development of focal brain edema following neuronal injury. Magnesium is also reported to work at the postsynaptic receptor to reduce the neurotoxic effect of glutamate. The present study was undertaken to examine the effect of postinjury treatment with Mg++ on brain edema and neurological outcome after traumatic brain injury. Sixty-nine rats that survived halothane anesthesia and closed head trauma (CHT) were randomly assigned to one of seven experimental groups: sham, CHT, and CHT with administration of Mg++ 1 hour postinjury. At 48 hours, brain tissue Mg++ concentration (calculated from optical density using a standard curve) was significantly increased compared to baseline levels (10.06 ± 2.44 mg/g vs. 6.83 ± 0.81 mg/g, p < 0.01 calculated by one-way analysis of variance). Also at 48 hours postinjury, brain tissue specific gravity in the contused hemisphere of Mg++-treated rats was significantly greater than that in the contused hemisphere of untreated rats, indicating attenuation of brain edema formation by Mg++. The neurological severity score (NSS) of rats treated with Mg++ improved significantly at both 18 and 48 hours, compared to baseline values obtained 1 hour after CHT but prior to administration of Mg++ (11.2 ± 2.5 vs. 15.2 ± 4.1, p = 0.03; and 12.3 ± 6.1 vs. 17.3 ± 3.6, p = 0.004, respectively). In the untreated groups, the NSS at 18 and 48 hours was not significantly different from baseline values (that is, no neurological improvement). The present study indicates that postinjury treatment with Mg++ attenuates brain edema formation and improves neurological outcome after experimental CHT.


1994 ◽  
Vol 81 (1) ◽  
pp. 93-102 ◽  
Author(s):  
Guo-Yuan Yang ◽  
A. Lorris Betz ◽  
Thomas L. Chenevert ◽  
James A. Brunberg ◽  
Julian T. Hoff

✓ There have been few investigations of brain edema formation after intracerebral hemorrhage (ICH), despite the fact that mass effect and edema are important clinical complications. The present study was designed to investigate the time course for the formation and resolution of brain edema and to determine how changes in cerebral blood flow (CBF) and blood-brain barrier (BBB) permeability are temporally related to edema formation following ICH. Anesthetized adult rats received a sterile injection of 100 µl of autologous blood into the caudate nucleus. Water and ion contents were measured immediately, at 4 and 12 hours, and daily to Day 7 (10 time points, six rats at each time) after experimental ICH. The water content of the ipsilateral basal ganglia increased progressively (p < 0.002) over the first 24 hours, then remained constant until after Day 5, when the edema began to resolve. Edema was most severe in the tissue immediately surrounding the hemorrhage; however, it was also present in the ipsilateral cortex, the contralateral cortex, and the basal ganglia. Measurements of local CBF (using [14C]-iodoantipyrine) and BBB permeability (using [3H]-α-aminoisobutyric acid) were obtained in separate groups of six to eight rats at various time intervals between 1 and 48 hours after ICH. Cerebral blood flow was reduced to 50% of control at 1 hour, returned to control values by 4 hours, but then decreased to less than 50% of control between 24 and 48 hours after ICH. The BBB permeability increased significantly prior to the occurrence of significant edema in the tissue surrounding the clot. However, BBB permeability in the more distant structures remained normal despite the development of edema. These results demonstrate a time course for the formation and resolution of brain edema following ICH similar to that observed during focal ischemia. Brain edema forms in the immediate vicinity of the clot as a result of both BBB disruption and the local generation of osmotically active substances and then spreads to adjacent structures. While local ischemia, due to the mass effect of the hemorrhage, may play a role in producing cytotoxic and vasogenic edema, the release of toxic substances from the clot should also be considered. Since edema is nearly maximal by 24 hours after ICH, therapy directed at reducing edema formation must be instituted within the 1st day.


1989 ◽  
Vol 71 (2) ◽  
pp. 233-238 ◽  
Author(s):  
Yukio Ikeda ◽  
Kiyomi Ikeda ◽  
Donlin M. Long

✓ Oxygen free radicals such as superoxide radical and iron-catalyzed hydroxyl radical generated by the superoxide system have been implicated in the genesis of brain edema. Therefore, deferoxamine (DFO), an iron chelator, could potentially be used to treat brain edema. To examine this hypothesis, vasogenic brain edema was produced in 48 cats by a cortical freezing lesion. The animals were separated into three groups: Group 1 comprised 14 cats that received no DFO and were sacrificed at 6 or 24 hours; Group 2 consisted of 12 cats that were treated with DFO (50 mg/kg/ml, intravenously) at 15 minutes before the lesion was made and 60 minutes later and were sacrificed at 6 or 24 hours; and Group 3 included 12 cats that were treated with DFO (50 mg/kg/ml, intravenously) at 15 minutes after the lesion was produced and 60 minutes later and were sacrificed at 6 or 24 hours. The effect of DFO on arterial blood pressure was also studied in the remaining 10 cats. Brain water content in eight sampling areas was measured by the specific gravity method. Blood-brain barrier disruption was assessed by spread of Evans blue dye with planimetry. Specific gravity values at 6 and 24 hours were significantly higher in Group 2 than in Group 1 animals. Areas of Evans blue dye extravasation at 6 and 24 hours were significantly reduced in Group 2 relative to Group 1. Group 3 cats showed improvement in specific gravity values and Evans blue extravasation at 6 hours, but not at 24 hours. The iron chelator DFO prevented early development of brain edema; thus, this oxygen free radical scavenger may provide a foundation for a new therapy for brain edema.


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