Al-Qattan K K, Khan I, Alnaqeeb M A, Ali M
Department of Biological Sciences, Faculty of Sciences, Kuwait University, Kuwait.
Prostaglandins Leukot Essent Fatty Acids. 2003 Oct;69(4):217-22. doi: 10.1016/s0952-3278(03)00087-5.
Garlic causes reduction in blood pressure (BP), however the role of Na/H exchanger (NHE) which mediates hypertension and related tissue-damage is poorly understood. In this study the effect of an established dose of raw garlic extract was investigated on the expression of NHE-1 and -3 and sodium pump activity in a 2K-1C model of hypertension in rats. 2K-1C animals showed high BP, increased serum concentration of PGE2 and TxB2, hypertrophy of the unclipped kidneys, but not in the clipped kidneys In addition, NHE-1 and NHE-3 isoforms were increased in both the 2K-1C kidneys, whereas alpha-actin was increased in the clipped but not in unclipped kidneys. Sodium pump activity was decreased in the clipped kidneys, but remained unchanged in the unclipped kidneys. Garlic treatment reduced the induction of NHE-1 only in the unclipped 2K-1C kidneys, whereas garlic treatment increased the sodium pump activity in both the 2K-1C kidneys. These findings demonstrate that the antihypertensive action of garlic is associated with a reversal of NHE-1 induction in the unclipped kidneys. Induction of NHE isoforms together with a reduced sodium pump activity might cause necrosis in the 2K-1C clipped kidneys due to cellular retention of Na+. On the other hand, activation of sodium pump by garlic extract in the kidneys should reduce intracellular Na+ concentration and normalize BP. These findings signify the use of garlic in the treatment of hypertension.
大蒜可降低血压(BP),然而,介导高血压及相关组织损伤的钠/氢交换体(NHE)的作用却鲜为人知。在本研究中,研究了既定剂量的生大蒜提取物对大鼠二肾一夹(2K-1C)高血压模型中NHE-1和NHE-3的表达以及钠泵活性的影响。2K-1C动物表现出高血压、血清PGE2和TxB2浓度升高、未夹闭肾脏肥大,但夹闭肾脏未出现肥大。此外,2K-1C双侧肾脏中NHE-1和NHE-3亚型均增加,而α-肌动蛋白在夹闭肾脏中增加,未夹闭肾脏中未增加。夹闭肾脏中钠泵活性降低,但未夹闭肾脏中保持不变。大蒜处理仅在未夹闭的2K-1C肾脏中降低了NHE-1的诱导,而大蒜处理增加了2K-1C双侧肾脏中的钠泵活性。这些发现表明,大蒜的降压作用与未夹闭肾脏中NHE-1诱导的逆转有关。NHE亚型的诱导以及钠泵活性降低可能由于细胞内钠离子潴留导致2K-1C夹闭肾脏坏死。另一方面,大蒜提取物激活肾脏中的钠泵应可降低细胞内钠离子浓度并使血压正常化。这些发现表明大蒜可用于治疗高血压。