心臟生物指標(biomaker)主要可以分為兩大類,分別是結構性蛋白及功能性蛋白。其中最常被應用的結構性蛋白為心臟肌鈣蛋白I (cardiac troponin I),負責測定各種造成心肌受損的疾病,是一種高敏感性及專一性的心臟生物指標。功能性蛋白N-terminal-pro B-type natriuretic peptide (NT-proBNP)是一種荷爾蒙,當細胞外液體過多造成心臟負擔時,心室壁會分泌此蛋白排出過多水分,維持體內正常循環。此論文包含兩個部份,第一部分研究心臟肌鈣蛋白I及NT-proBNP在健康及心臟瓣膜疾病之心衰竭患犬的血清濃度,第二部分研究治療前後心臟瓣膜疾病之心衰竭患犬心臟肌鈣蛋白I的濃度差異。研究結果指出心衰竭患犬血清的心臟肌鈣蛋白I及NT-proBNP濃度都明顯比健康犬高(分別為P=0.02, P<0.001),而且發現當心衰竭愈嚴重,血清中的心臟肌鈣蛋白I及NT-proBNP濃度愈高(分別為P=0.02, P<0.0001)。血清中心臟肌鈣蛋白I濃度,在治療後雖然明顯下降,但在統計結果並沒有顯著差異性存在(P=0.09)。根據此次的研究結果顯示測量血清中心臟肌鈣蛋白I及NT-proBNP濃度可以做為篩選是否罹患心臟疾病,並預測心衰竭嚴重程度。
Biomarkers have been extensively used in human and veterinary medicine, and divided into two groups: the leakage markers and functional makers. Cardiac troponin I (cTnI), a structure protein of cardiomyocyte, is a sensitive, specific, is a leakage marker for cardiac injury. N-terminal-pro B-type natriuretic peptide (NT-proBNP), a hormone exerts a variety of effects of maintaining circulatory homeostasis in states of increased extracellular volume, is a functional maker. The thesis includes two sections: first part, association NT-proBNP and cTnI of clinically healthy dogs and dogs with heart failure (HF); second part, changes of cTnI concentrations before and after treatment for HF. The result of this study illustrated that concentrations of NT-proBNP and cTnI in the dogs with HF were higher than those in the control dogs (P<0.001, P=0.02, respectively), and these two cardiac makers were positively associated with severity of HF (P<0.0001, P=0.02, respectively). Serum cTnI concentrations decreased after treatment, but not reach significant different (P=0.09). Based on these findings, both cardia markers were able to identify presence of cardiac disease, and determine severity of HF in dogs.