title: Reduction of salt sensitivity in stroke-prone spontaneously hypertensive rats administered an AT1 receptor antagonist during suckling.
abstract: BACKGROUND
  In this study, antihypertensive therapy was started during suckling and the effect on blood pressure (BP) and salt sensitivity of stroke-prone spontaneously hypertensive rats (SHRSP) was determined.
  
  
  METHODS
  The SHRSP were treated with an AT1 receptor antagonist (losartan: 100 mg/L in drinking water) from 2 to 4 weeks of age. After stopping treatment at 4 weeks of age, the control group and the losartan group were fed a commercial diet with tap water ad libitum until 10 weeks of age. Both the control and losartan groups were switched to 1% saline at the age of 10 weeks.
  
  
  RESULTS
  Salt loading was started at 10 weeks of age, with BP levels of 203+/-3 and 199+/-6 mm Hg for the control group and the losartan group, respectively, at that age. After 4 weeks of salt loading, BP levels were 253+/-7 mm Hg in the control group and 242+/-5 mm Hg in the losartan group, showing a mild elevation in the losartan group. The life span of the losartan group (104+/-78 days) was significantly greater than that of the control group (37+/-17 days). Plasma aldosterone concentrations of the losartan group were lower than those of the control group at 4 and 15 weeks of age.
  
  
  CONCLUSIONS
  We have demonstrated the renin-angiotensin-aldosterone system may play a key role in the establishment of end-organ salt sensitivity, and the period of lactation in critical for salt sensitivity in later life.
authors.affiliation: Division of Advanced Life Sciences, Graduate School of Agriculture, Kinki University, Nara, Japan.
authors.forename: Lila
authors.initials: L
authors.lastname: Otani
authors.forename: Tomohide
authors.initials: T
authors.lastname: Yasumatsu
authors.forename: Megumi
authors.initials: M
authors.lastname: Murakami
authors.forename: Atsumi
authors.initials: A
authors.lastname: Hayashi
authors.forename: Koichi
authors.initials: K
authors.lastname: Kimoto
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Murakami
mesh_terms: D000419:Albuminuria / Q000139:chemically induced; D000450:Aldosterone / Q000097:blood; D000704:Analysis of Variance; D047228:Angiotensin II Type 1 Receptor Blockers / Q000494:pharmacology*; D000818:Animals; D000833:Animals, Suckling; D000959:Antihypertensive Agents / Q000494:pharmacology; D015415:Biomarkers / Q000097:blood / Q000652:urine; D001794:Blood Pressure / Q000187:drug effects; D004195:Disease Models, Animal; D019808:Losartan / Q000494:pharmacology; D008297:Male; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D012083:Renin / Q000097:blood / Q000187:drug effects; D017673:Sodium Chloride, Dietary / Q000009:adverse effects / Q000494:pharmacology*; D020521:Stroke / Q000139:chemically induced / Q000503:physiopathology*; D013997:Time Factors
chemical_list: D047228:Angiotensin II Type 1 Receptor Blockers; D000959:Antihypertensive Agents; D015415:Biomarkers; D017673:Sodium Chloride, Dietary; D000450:Aldosterone; D012083:Renin; D019808:Losartan