Effects of Ginkgo biloba extract feeding on salt-induced hypertensive Dahl rats.
We previously demonstrated that Ginkgo biloba extract (GBE) produced vasodilation via the nitric oxide synthesis and release by increasing the intracellular calcium level in vascular endothelial cells of rats. The present study aimed to clarify the effects of dietary administration of GBE on the blood pressure and vascular tone of hypertensive Dahl salt-sensitive (Dahl) rats in order to evaluate its therapeutic actions and availability. Dahl rats were fed an 8.0% NaCl diet or an 8.0% NaCl plus 0.5% GBE diet for 24 d. The feeding of GBE did not change the heart rate, but significantly decreased systolic blood pressure. After 24 days' administration, the effects of GBE on the atria and aorta isolated from Dahl rats were examined. The GBE-containing diet did not affect the negative and positive actions of isolated atria that were produced by acetylcholine and isoproterenol, respectively. In the aortic preparations, the relaxation in response to acetylcholine was significantly potentiated by a GBE-containing diet. Sodium nitroprusside-induced relaxation was unchanged by GBE-containing diet. These results demonstrated that GBE reduced salt-related elevation of blood pressure and restored the impaired acetylcholine-induced vasodilation in aortic segments.
Kubota
Yoko
Y
Department of Pharmacology, School of Pharmaceutical Sciences, Mukogawa Women's University, Nishinomiya 663-8179, Japan.
Tanaka
Naoko
N
Kagota
Satomi
S
Nakamura
Kazuki
K
Kunitomo
Masaru
M
Umegaki
Keizo
K
Shinozuka
Kazumasa
K
D000109:Acetylcholine / Q000494:pharmacology; D000284:Administration, Oral; D000818:Animals; D000959:Antihypertensive Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D001013:Aorta, Thoracic / Q000187:drug effects; D001794:Blood Pressure / Q000187:drug effects*; D020441:Ginkgo biloba; D006339:Heart Rate / Q000187:drug effects*; D006973:Hypertension / Q000188:drug therapy* / Q000209:etiology / Q000503:physiopathology; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D010936:Plant Extracts / Q000008:administration & dosage / Q000627:therapeutic use*; D051381:Rats; D020303:Rats, Inbred Dahl; D017673:Sodium Chloride, Dietary / Q000009:adverse effects; D014664:Vasodilation / Q000187:drug effects*; D000096983:Ginkgo Extract
D000109:Acetylcholine; D000959:Antihypertensive Agents; D007545:Isoproterenol; D010936:Plant Extracts; D017673:Sodium Chloride, Dietary; C063170:Ginkgo biloba extract; D000096983:Ginkgo Extract