Myocardial Imaging Following Superior Cervical Ganglionectomy in Adult Rats

• Main Authors: Chieh-Ling Kao, 高潔靈
• Other Authors: Cheng C.Y.
• Format: Others
• Language: zh-TW
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/24291882348945999770

碩士 === 國防醫學院 === 生物及解剖學研究所 === 95 === Sympathetic nerve activity may address a crucial issue in the evaluation of the cardiac function. To assess the myocardial sympathetic activity, cardiac neuroimaging such as nuclear imaging, electrophysiology and norepinephrine transporter (NET) distributions, emerged as importantly direct measurements. Hence, we use these three ways (nuclear imaging, physiological recordings and NET immunohistochemistry) to investigate the cardiac function after the surgical ganglionectomy (Gx). Purpose: To establish an animal model of suppression of myocardial sympathetic innervation applying in heart studies, this current study will demonstrate the feasibilities of 123I-metaiodobenzylguanidine (123I-MIBG) and 11C-hydroxyephedrine (11C-HED) myocardial imaging, physiological recordings, and NET immunohistochemistry for monitoring myocardial sympathetic innervation following at superior cervical ganglionectomy. Methods: All SD rats are divided into 3 groups which are normal group, right-Gx (Rt-Gx) group, and left-Gx (Lt-Gx) group. After Gx, all rats were recorded of their electrocardiogram (ECG), heart rate (HR), blood pressure (BP), and scanned by conventional nuclear imaging and then the heart tissue were removed to process immunohistochemistry staining. Furthermore, the heat shock-induced responses were also recorded with the ECG, HR, and BP. Results: The imaging of the Lt-Gx group is similar to the normal group, but the imaging of the Rt-Gx group is different from the normal group, (the region of interest (ROI) is lighter and smaller, the counts are lower). The average of heart-to-mediastinum activity ratio (H/M ratio) and myocardial washout of 123I-MIBG (MWO) of the Rt-Gx and the Lt-Gx groups are both lower than the normal group. For the physiological recordings, the HR and BP of the Rt-Gx and the Lt-Gx groups are similar to the normal group. The ECG of the three groups are different. The P waves and QRS complexs of Rt-Gx and Lt-Gx were emplified, and the T waves were reversed. Moreover, the records of heat shock-induced response were showed that the BP of the Rt Gx group were obviously lower than the other two groups, but the HR were not different from each other. In addition, the variations of NET morphology were detected at the Rt-Gx and the Lt-Gx groups. Conclusion: Non-invasive nuclear imaging can be a possible technique in earlier demonstration of sympathetic denervation in Gx rats than conventional physiological techniques. According to the physiological parameters, we suggest that the superior cervical ganglion may influence more in the blood pressure than in the heart rate. Furthermore, Gx rat may be a successful animal model of suppression of myocardial sympathetic innervation applying in heart studies.