Effects of calcitonin gene related peptide in cisterna magna on cerebral vasospasm after experimental subarachnoid hemorrhage in rats

Abstract

Objective To explore the effects of application calcitonin gene related peptide(CGRP)in cisterna magna on cerebral vasospasm after experimental subarachnoid hemorrhage (subarachnoid hemorrhage, SAH) in rat models. Methods 64 male Wistar rats were randomly divided into 4 groups. Group A was normal control group. After the subarachnoid hemorrhage models were established, group B, C, D were given normal saline, CGRP and adenovirus CGRP through cisterna magna respectively. White blood cells in cerebrospinal fluid were detected by automatic blood analyzer, CGRP activity was detected by enzyme linked immunosorbent assay, circulating endothelial cells were observed through laser scanning confocal microscope and parietal cortex regional cerebral blood flow were observed by laser doppler flowmeter. Basilar artery vasospasm and arterial blood gas analysis were detected by digital subtraction angiography and blood gas analyzer respectively. Results Before and after administration, there were no statistical differences in white blood cells and artery blood gas among the 4 groups (both P>0.05). After administration 48 h , compared with group A, concentrations of CGRP in cerebrospinal fluid group B(0.006±0.002) did not increase (P>0.05), but increased 200 times in Group C ((1.160±0.170)nmol/L, P 0.05). Conclusion Cerebral vasospasm after SAH can be effectively improved by administration CGRP in cisterna magna. Adenovirus CGRP effect is better than CGRP. Key words: Calcitonin gene related peptide; Rats; Subarachnoid hemorrhage; Cerebral vasospasm