dizocilpine-maleate and Hematoma--Subdural--Acute

Cerebral ischemia due to secondary injuries plays an important role in the high mortality rate of acute subdural hematoma (SDH). Although promising results were obtained from experimental works with excitatory amino acid (EAA) antagonists which inhibit the excitotoxic mechanism in the development of cerebral ischemia, these agents could not be used clinically due to their psychomimetic side effects. Memantine, also an EAA antagonist, has been used for a long time in the treatment of different neurodegenerative diseases; however, it was not used in treatment of acute subdural hematoma before. This study has been designed to investigate the development of cerebral ischemia and ischemic edema under experimental acute subdural hematoma and the effect of memantine (Sigma M-9292) and MK-801 (Sigma M-107) in the treatment of ischemia.. Forty-two adult female Sprague-Dawley rats were divided into two groups: Group A for investigation of ischemia related to SDH and its treatment, and Group B for investigation of cerebral edema. Both groups were further divided into five subgroups, i.e. for sham operations, formation of SDH and treatment with saline, MK-801 and memantine. Treatment of cerebral edema could not be investigated because formation of cerebral edema could not be proven statistically. For evaluation of ischemia, the ratio of ischemic area/the total brain area was calculated as percentages in coronal slices of the rats' brains.. In all of the evaluated slices, statistical analysis showed that treatment with MK-801 as well as memantine reduced ischemia caused by SDH.. Our study showed that memantine, which is already considered as a safe treatment alternative for other central nervous system (CNS) diseases, can be useful in the treatment of acute SDH as well.

Topics: Animals; Brain Edema; Brain Ischemia; Disease Models, Animal; Dizocilpine Maleate; Excitatory Amino Acid Antagonists; Female; Functional Laterality; Hematoma, Subdural, Acute; Memantine; Rats; Rats, Sprague-Dawley; Statistics, Nonparametric

Increased glutamate concentration in the cerebrospinal fluid has been reported in severely head-injured patients, suggesting that an excessive release of glutamate may be involved in the process of neuronal damage. Ischaemic damage after subdural haematoma has been reported to be reduced by glutamate (N-methyl-D-aspartate: NMDA) receptor antagonists such as dizocilpine and CGS 19755; even though these drugs were given 20-30 min after insult. Excessive release of excitatory amino acids may produce the neural damage after subdural haematoma and NMDA receptor antagonists may become valuable therapeutic drugs. This study compared the effects of ketamine and dizocilpine, on intracranial pressure and histopathological changes after acute subdural haematoma produced by an injection of autologous blood (150 microL) in rats.. The control (n = 9), ketamine (n = 9) and dizocilpine (n = 9) groups, respectively, received saline, ketamine (total dose: 210 mg kg-1) or dizocilpine (total dose: 1.0 mg kg-1) from 0.5 to 8 h after acute subdural haematoma. A silicone group (n = 9) had the same volume of silicone injected subdurally.. The volume of ischaemic damage in the silicone group (1.3 +/- 1.2 mm3) was significantly smaller than in the control group (11.9 +/- 3.8 mm3). Ketamine and dizocilpine did not increase intracranial pressure. Dizocilpine significantly decreased the volume of ischaemic damage (6.1 +/- 3.8 mm3). Ketamine failed to significantly decrease damage (7.8 +/- 5.0 mm3).. These results suggest that the factors elicited by the clotted blood contribute to the ischaemic damage after subdural haematoma, and that the glutamate receptor antagonist dizocilpine reduces the damage, while ketamine shows only a trend reduction of the damage.

Topics: Animals; Blood Glucose; Body Temperature; Brain; Cholinesterase Inhibitors; Dizocilpine Maleate; Electroencephalography; Hematoma, Subdural, Acute; Hypoxia-Ischemia, Brain; Intracranial Pressure; Male; Neuroprotective Agents; Rats; Rats, Wistar