Myocardial hypertrophy in rats with renal insufficiency.
Increased defatted dry wt of the heart and increased heart calcium content were observed in subtotally nephrectomized male Sprague-Dawley rats compared with sham-operated pairfed controls. Increased heart wt contrasted with no change of the weight of viscera (liver, spleen) and markedly decreased weight of striated muscle. Heart wt was unchanged after 5 days of renal insufficiency, but significantly increased after 14 or 21 days. Increased heart wt persisted despite effective beta adrenoreceptor blockade (2 X 10 mg metroprolol/kg/day i.p.) or effective alpha-1-adrenoreceptor blockade (2 X 2 mg prazosin/kg/day i.p.). Increased heart wt was also demonstrable despite normalization of basal blood pressure (intraarterial blood pressure measurement in conscious animals): blood pressure was lowered in one series with hydralazine/nadolol in drinking water (calculated to deliver 20 and 2 mg/kg/day, respectively) and in another series with furosemide in drinking water (15 mg/kg/day) combined with metoprolol (2 X 10 mg/kg/day i.p.). Increased heart wt was also noted despite correction of anemia by blood transfusion (Hct greater than 40%) and after parathyroidectomy in animals kept eucalcemic with high dietary calcium. Micromorphometry of left ventricular myocardium in perfusion-fixed tissue showed no significant change of the relative proportion of connective tissue and myocardial fibers. Myocardial isomyosin pattern was changed with an increase of fast-migrating V1 isomyosin in animals with renal insufficiency compared to sham-operated pairfed controls.
D000251:Adenosine Triphosphatases / Q000378:metabolism; D000818:Animals; D001794:Blood Pressure; D001803:Blood Transfusion; D002118:Calcium / Q000037:antagonists & inhibitors / Q000378:metabolism; D006332:Cardiomegaly / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D006830:Hydralazine / Q000494:pharmacology; D007527:Isoenzymes / Q000378:metabolism; D007674:Kidney Diseases / Q000150:complications* / Q000209:etiology; D008297:Male; D008790:Metoprolol / Q000494:pharmacology; D008854:Microscopy, Electron; D009206:Myocardium / Q000378:metabolism / Q000473:pathology; D009218:Myosins / Q000378:metabolism; D009248:Nadolol; D009392:Nephrectomy; D009929:Organ Size / Q000187:drug effects; D010280:Parathyroid Glands / Q000502:physiology; D011224:Prazosin / Q000494:pharmacology; D011412:Propanolamines / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D014268:Trifluoperazine / Q000494:pharmacology
D007527:Isoenzymes; D011412:Propanolamines; D014268:Trifluoperazine; D006830:Hydralazine; D009248:Nadolol; D000251:Adenosine Triphosphatases; D009218:Myosins; D008790:Metoprolol; D002118:Calcium; D011224:Prazosin