The expression and changes of heat shock protein 70, MDA and haemorheology in rat cortex after diffuse axonal injury with secondary insults

• Published in: Journal of clinical neuroscience Vol. 8; no. 3; pp. 250 - 252
• Main Authors: Zhou, Fei, Xiang, Zhang, Peiling, Lu, Junjie, Jing, Xian Zhen, Liu
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 01.05.2001; Elsevier
• Subjects: Animals; Axons - metabolism; Axons - pathology; Biological and medical sciences; Blood Viscosity; brain diffuse axonal insults, secondary insults, heat shock protein-70, malonyldialdehyde, haemorheology; Brain Injuries - metabolism; Brain Injuries - pathology; Cerebral Cortex - blood supply; Cerebral Cortex - chemistry; Cerebral Cortex - metabolism; Cerebrovascular Circulation; Disease Models, Animal; Free Radicals - metabolism; Hemorheology; HSP70 Heat-Shock Proteins - analysis; HSP70 Heat-Shock Proteins - metabolism; Hypotension - metabolism; Hypotension - pathology; Immunohistochemistry; Injuries of the nervous system and the skull. Diseases due to physical agents; Male; Malondialdehyde - analysis; Malondialdehyde - metabolism; Medical sciences; Rats; Rats, Sprague-Dawley; Rotation; Traumas. Diseases due to physical agents; Tropical medicine; brain diffuse axonal insults, secondary insults, heat shock protein-70, malonyldialdehyde, haemorheology; Nervous system diseases; Pathophysiology; Rat; Rheology; Craniocerebral; Rodentia; Diseases of the osteoarticular system; Gene expression; Trauma; Cerebral disorder; Vertebrata; Experimental disease; Mammalia; Animal; Central nervous system disease; Heat shock protein; Skull disease
• ISSN: 0967-5868; 1532-2653
• DOI: 10.1054/jocn.2000.0760

In the present study the role of heat shock protein 70 (HSP70) expression, changes of malonyldialdehyde (MDA) in rat cortex and haemorheology with time after diffuse axonal injury (DAI) only and DAI with secondary insults (SI) were studied. The rat DAI and DAI with SI model were made according to our previous work and animals were divided into a control and another five injury groups with time after injury. Immunohistochemical assay was used to detect the neuronal expression of HSP70 at 0.5h, 3h, 12h, 24h, 72h after DAI or DAI with SI. In the meantime, the high (ηh ) and low whole blood viscosity (ηL ), haematocrit (HCT) and RBC aggregation index (AI = ηL/ηh ) were also detected and calculated. MDA in the homogenised brain tissue was assayed by thiobarbituric acid (TBA) reaction. The results showed that HSP70 positive neurons were not detected at 30 minutes, but the number of HSP70 positive neurons begin to increase obviously at 3 hours, reach a peak at 24 hours (P< 0.01), and decrease at 72 hours (P= 0.05) after brain injury. The trend of expression of HSP70 was alike for both DAI only or DAI with SI. Meanwhile, MDA, ηh, ηL , HCT and AI changes showed the same tendency. Compared with DAI only group, MDA and blood viscosity indexes in DAI with SI were significantly higher at respective time points (P< 0.01). It is concluded that HSP70 expression, MDA and haemorheology indices increased after brain injury and brain injury with SI. Free radicals and haemorheological changes play an important role in the aggravation of brain damage and HSP70 expression upregulation.