Copper deficiency in a genetically hypertensive cardiomyopathic rat: electrocardiogram, functional and ultrastructural aspects.
The effect of copper deficiency on cardiac function and structure was studied in a strain of rats (SHHS/Mcc-cp) known to develop cardiac failure as adults. Restriction of dietary copper (less than or equal to 1 mg/kg vs. 6 mg/kg in adequate diets) at weaning in both sexes for a 6-wk period produced cardiac hypertrophy. Male rats developed more severe copper-deficiency symptoms than their female counterparts. In both sexes of copper-deficient rats, there was an increase in cardiac length, width, free ventricular wall thickness and septum thickness. Electrocardiographic tracings revealed greater QRS height among male copper-deficient rats. Heart rate also was substantially reduced in this group. The increased volume of myocardium occupied by mitochondria in the copper-deficient male rats might result in increased electrical resistance that would increase the QRS height; hypertrophy or anemia also could be contributory. Some male copper-deficient rats had prolongation of the QRS in a bundle branch block pattern. Maximal rates of rise and fall for left ventricular pressure were reduced in male copper-deficient rats. The gross histology indicated that this type of heart failure was more concentric than eccentric. The copper-deficient male rat may serve as a useful model for studying the concentric cardiac hypertrophy that occurs in humans.
Medeiros
D M
DM
Department of Human Nutrition and Food Management, Ohio State University, Columbus 43210-1295.
Liao
Z
Z
Hamlin
R L
RL
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D009202:Cardiomyopathies / Q000235:genetics* / Q000503:physiopathology; D003300:Copper / Q000008:administration & dosage / Q000172:deficiency*; D004032:Diet; D004562:Electrocardiography; D005260:Female; D006321:Heart / Q000187:drug effects; D006973:Hypertension / Q000235:genetics*; D008297:Male; D009206:Myocardium / Q000473:pathology / Q000648:ultrastructure; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D012737:Sex Factors; D016277:Ventricular Function, Left
D003300:Copper