Nitric oxide mediates the blood-pressure lowering effect of garlic in the rat two-kidney, one-clip model of hypertension.
Garlic reduces blood pressure (BP) in two-kidney, one-clip (2K-1C) rats, and enhances nitric oxide (NO) synthesis in in vivo and in vitro experiments. NO is an important modulator of BP in the 2K-1C model. This study investigated the role of NO in the BP-lowering effect of garlic in the 2K-1C model. BP readings (mm Hg) were obtained from 2K-1C rats in 4 groups treated intraperitoneally for 2 wk with either normal saline (NS), garlic, L-nitroarginine-methylester (L-NAME), or L-NAME+garlic (n=4x5). BP was determined using the tail-cuff method and compared with data of 4 similarly treated groups of normal (unclipped) rats (NRs). The BP readings of NR groups were 120+/-3 mm Hg for the NS-treated group, 120+/-2 mm Hg for the garlic-treated group, 167+/-3 mm Hg for the L-NAME treated group (higher than NS or garlic, P<0.001) and 128+/-5 mm Hg for the garlic+L-NAME-treated group (lower than L-NAME, P<0.001). The BP readings of 2K-1C rat groups were: for the NS group, 169+/-6 mm Hg (higher than NRs, P<0.001); for the garlic group, 116+/-7 mm Hg (lower than NS, P<0.001); for the L-NAME group: 184+/-8 mm Hg (higher than garlic, P<0.001), and for the L-NAME+garlic group: 130+/-6 mm Hg (lower than garlic or NS, P<0.001). The data show that L-NAME increases the BP of both NRs and 2K-1C rats, with the rise more evident in the NRs (39 vs. 9%, respectively). Garlic counteracts the hypertensive effect of L-NAME in NRs as well as 2K-1C rats. We conclude that the BP-lowering effect of garlic in the rat 2K-1C model may be partly mediated through the NO pathway.
Department of Biological Sciences, Faculty of Science, Kuwait University, Safat 13060, Kuwait. qattan@kuc01.kuniv.edu.kw
Khaled K
KK
Al-Qattan
Martha
M
Thomson
Sausan
S
Al-Mutawa'a
Dalal
D
Al-Hajeri
Hana
H
Drobiova
Muslim
M
Ali
D000704:Analysis of Variance; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology*; D004195:Disease Models, Animal; D006977:Hypertension, Renal / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000502:physiology*; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012016:Reference Values
D010936:Plant Extracts; D009569:Nitric Oxide; D019331:NG-Nitroarginine Methyl Ester