title: Pressure-overload hypertrophy is unabated in mice devoid of AT1A receptors.
abstract: Mechanisms controlling cardiac growth are under intense investigation. Among these, the renin-angiotensin system has received great interest. In the current study, we tested the hypothesis that the renin-angiotensin system was not an obligate factor in cardiac hypertrophy. We examined the left ventricular hypertrophic response to a pressure overload in mice devoid of the AT1A receptor, the putative major effector of the growth response of the renin-angiotensin system. Aortic banding produced similar transband gradients in wild-type and AT1A knockout mice. The left ventricular mass-to-body weight ratio increased from 3.44 +/- 0.08 to 5.62 +/- 0.25 in wild-type ascending aortic-banded mice. The response in the knockout mice was not different (from 2.97 +/- 0.13 to 5.24 +/- 0.37). We conclude that the magnitude of cardiac hypertrophy is not affected by the absence of the AT1A receptor and its signaling pathway and that this component of the renin-angiotensin system is not necessary in cardiac hypertrophy.
authors.affiliation: Department of Medicine, Gazes Cardiac Research Institute, Medical University of South Carolina, Charleston 29425, USA.
authors.forename: M
authors.initials: M
authors.lastname: Hamawaki
authors.forename: T M
authors.initials: TM
authors.lastname: Coffman
authors.forename: A
authors.initials: A
authors.lastname: Lashus
authors.forename: M
authors.initials: M
authors.lastname: Koide
authors.forename: M R
authors.initials: MR
authors.lastname: Zile
authors.forename: M I
authors.initials: MI
authors.lastname: Oliverio
authors.forename: G
authors.initials: G
authors.lastname: DeFreyte
authors.forename: G
authors.initials: G
authors.lastname: Cooper
authors.forename: B A
authors.initials: BA
authors.lastname: Carabello
mesh_terms: D000804:Angiotensin II / Q000502:physiology*; D000818:Animals; D001794:Blood Pressure; D001835:Body Weight; D006332:Cardiomegaly / Q000209:etiology*; D006579:Heterozygote; D051379:Mice; D018345:Mice, Knockout; D044140:Receptor, Angiotensin, Type 1; D011945:Receptors, Angiotensin / Q000172:deficiency*; D012083:Renin / Q000502:physiology
chemical_list: D044140:Receptor, Angiotensin, Type 1; D011945:Receptors, Angiotensin; D000804:Angiotensin II; D012083:Renin