The Dynamic Changes Of Brain Intracellular Ca²⁺ Levels And The Relationship Of The Ca²⁺ And CGRP After TBI

Objective The calcium was investigated in the traumatic brain injury (TBI) caused by a series of path physiological changes, and further the relationship between the the calcium ions and the calcitonin gene-related Peptide (CGRP) was researched.Methods Animal model of traumatic brain injury were constructed by epidural freefall using Wistar rats. The calcium concentration and the plasma CGRP levels were got by laser scanning confocal microscope and enzyme-linked immunosorbent assay (ELISA), respectively on the normal control group (36 not against) and experimental group(108 against) at different time points, such as 2h,6h,12h,24h,48h,72h. The data was analyzed by single-factor analysis of variance; two factors factorial design analysis of variance, Pearson correlation analysisResults In the control group calcium fluorescence intensity remained at a relatively low level in the brain cell, there were significant differences of the brain cells calcium fluorescence intensity between the experimental group and the control group (P<0.01), that is significantly higher about two hours after injury, peak at about 24 hours and a downward trend about 48 hours. There were significant differences of the brain cells calcium fluorescence intensity between the severe group and the mild and moderate group (P<0.05).The rat brain cells calcium fluorescence intensity level gradually increased with the degree of injury . There were significant differences of the plasma CGRP levels between each experimental group and the control group at different time points (P<0.05).In the experimental groups the level of CGRP increased at first and then decreased and increased slowly. There were significant differences of the plasma CGRP levels between severe group and the mild-moderate group (P<0.05).The plasma CGRP levels decreased with the degree of brain damage increased. The brain intracellular calcium ion concentration and the CGRP level were negatively correlated after brain injury.Conclusion Calcium overload played an important in the brain secondary damage after TBI. There was a negative correlation between CGRP and brain intracellular calcium level.CGRP could reduce the calcium concentration in traumatic brain injury.