title: Isoproterenol-induced hypertrophied rat hearts: does short-term treatment correspond to long-term treatment?
abstract: In consideration of clinical implications, it is often complained that short-term experimental diseased heart models do not mimic long-term diseased hearts that are often clinically encountered. The aim of the present study was (i) to compare the left ventricular function between rat cardiac hypertrophy models treated with isoproterenol for 3 days (Iso 3d) and 7 days (Iso 7d) by pressure-volume measurements with a catheter method, and (ii) to follow up the left ventricular function in the same model treated with Iso up to 16 weeks with a less-invasive echocardiography. An infusion of either Iso (1.2 mg x kg(-1) x day(-1) for 3 days-16 weeks) or vehicle (saline 24 microl x day(-1) for 3 days-16 weeks; Sa group) was performed by subcutaneously implanting an osmotic minipump. There were no significant differences in the systolic pressure-volume area at midrange left ventricular volume (PVA(mLVV): a mechanical work capability index) between Iso 3d and 7d groups, though PVA(mLVV) in both groups was significantly reduced from that in the Sa group. From echocardiography, the left ventricular function of the hypertrophy models at 3 days, 1 week, and 2 weeks was unchanged, but the model at a term longer than 4 weeks resulted in prolonged systolic failure. The results indicated that (i) no marked differences in the left ventricular mechanical work capability were found between the Iso 3d and 7d groups, and that (ii) only a 3-day Iso infusion induced the hypertrophy model similar in shape and function to that induced by a 2-week Iso infusion. We concluded that the 3-day model was sufficient.
authors.affiliation: Department of Physiology II, Nara Medical University School of Medicine, Nara, 634-8521 Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Takeshita
authors.forename: Juichiro
authors.initials: J
authors.lastname: Shimizu
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Kitagawa
authors.forename: Daisuke
authors.initials: D
authors.lastname: Yamashita
authors.forename: Kiyoe
authors.initials: K
authors.lastname: Tohne
authors.forename: Chikako
authors.initials: C
authors.lastname: Nakajima-Takenaka
authors.forename: Haruo
authors.initials: H
authors.lastname: Ito
authors.forename: Miyako
authors.initials: M
authors.lastname: Takaki
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D015153:Blotting, Western; D002306:Cardiac Volume / Q000187:drug effects; D002316:Cardiotonic Agents / Q000494:pharmacology*; D004195:Disease Models, Animal; D004452:Echocardiography; D006321:Heart / Q000033:anatomy & histology / Q000502:physiology*; D017379:Hypertrophy, Left Ventricular / Q000139:chemically induced*; D007545:Isoproterenol / Q000494:pharmacology*; D008297:Male; D009929:Organ Size / Q000187:drug effects; D051381:Rats; D013318:Stroke Volume / Q000187:drug effects; D013816:Thermodynamics; D013997:Time Factors
chemical_list: D002316:Cardiotonic Agents; D007545:Isoproterenol