Influence of long-term arotinolol treatment on myocardial mechanics and ventricular myosin isoenzymes in spontaneously hypertensive rats.
Alterations in myocardial mechanics and left ventricular myosin isoenzymes by long-term treatment of hypertension with arotinolol were examined in spontaneously hypertensive rats. Approximately 20 mg/kg/day arotinolol was administered to 22-week-old male spontaneously hypertensive rats for 8-10 weeks. There was no significant difference in systolic blood pressure between arotinolol-treated and untreated rats. However, ventricular weight tended to decrease in the arotinolol-treated group, although not significantly. There were no significant differences in isometric developed tension and dT/dtmax of isolated left ventricular papillary muscles between the arotinolol-treated and untreated groups. The left ventricular myosin isoenzyme pattern, on the other hand, obtained by pyrophosphate gel electrophoresis, showed a significant shift toward VM-1 as a result of long-term arotinolol treatment.
Department of Internal Medicine, Aoto Hospital, Jikei University, Tokyo, Japan.
N
N
Takeda
T
T
Ohkubo
T
T
Iwai
A
A
Tanamura
M
M
Nagano
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D006321:Heart / Q000187:drug effects*; D006339:Heart Rate / Q000187:drug effects; D006973:Hypertension / Q000201:enzymology*; D007527:Isoenzymes / Q000378:metabolism; D007741:Labetalol / Q000494:pharmacology; D009206:Myocardium / Q000201:enzymology; D009218:Myosins / Q000378:metabolism*; D010210:Papillary Muscles / Q000187:drug effects; D011412:Propanolamines / Q000494:pharmacology*; D011433:Propranolol / Q000494:pharmacology; D051381:Rats; D011918:Rats, Inbred SHR
D000319:Adrenergic beta-Antagonists; D007527:Isoenzymes; D011412:Propanolamines; C024523:arotinolol; D011433:Propranolol; D009218:Myosins; D007741:Labetalol