Garlic prevents hypoxic pulmonary hypertension in rats

Abstract

Hypoxic pulmonary vasoconstriction underlies the development of high-altitude pulmonary edema. Anecdotal observations suggest a beneficial effect of garlic in preventing high-altitude symptoms. To determine whether garlic influences pulmonary vasoconstriction, we assessed the effect of garlic on pulmonary pressures in rats subjected to alveolar hypoxia and on vasoconstriction in isolated pulmonary arterial rings. Garlic gavage (100 mg/kg body wt) for 5 days resulted in complete inhibition of acute hypoxic pulmonary vasoconstriction compared with the control group. No difference in mean arterial pressure or heart rate response to hypoxia was seen between the groups. Garlic solution resulted in a significant dose-dependent vasorelaxation in both endothelium-intact and mechanically endothelium-disrupted pulmonary arterial rings. The administration of N G-nitro-l-arginine methyl ester (a nitric oxide synthase inhibitor) inhibited the vasodilatory effect of garlic by 80%. These studies document that garlic blocks hypoxic pulmonary hypertension in vivo and demonstrate a combination of endothelium-dependent and -independent mechanisms for the effect in pulmonary arterial rings.

An In Vitro Study of Different Extracts and Fractions of Allium sativum (Garlic): Vascular Reactivity

“…NE Krebs: contraction with NE in normal Krebs; NE 0Ca1: first contraction with NE in Ca 2+ -free Krebs; NE 0Ca2: second contraction with NE in Ca 2+ -free Krebs. and the implication of calcium channels (3).…”

“…However, a controversy exists about its mechanism of action. Several authors have proposed a mechanism of action mediated by the activation of nitric oxide synthase in vascular endothelium (2), but a direct effect on vascular smooth muscle has also been demonstrated, suggesting the occurrence of vasodilatation via smooth muscle cell membrane hyperpolarization and/ or inhibition of the opening of calcium channels (3). Together these observations suggest that garlic might block the development of hypertension associated with atherosclerosis, the principal contributor to myocardial and cerebral infarction.…”

The Functional Role of Garlic and Bioactive Components in Cardiovascular and Cerebrovascular Health: What We Do Know

“…Fallon et al [31] reported that garlic inhibited acute hypoxic pulmonary vasoconstriction in rats and elicited appreciable dose-dependent vasorelaxation in both endothelium-intact and mechanically endothelium-disrupted pulmonary arterial rings. This implies that it can combine both endothelium-dependent and independent process in its hypotensive property [31] [32].…”

“…This implies that it can combine both endothelium-dependent and independent process in its hypotensive property [31] [32]. In vitro study by [33] indicated that garlic juice can relax the muscles of aorta, trachea, intestines and isolated rabbit heart.…”

Activation of Immune Responses in Mice by an Oral Administration of Bunching Onion (Allium fistulosum) Mucus

“…9) Other members of the Allium family (e.g., garlic and onion) have also been used as antihypertensives, antiatherosclerotics, antithrombotics, antihyperlipidemics, and antioxidants. [10][11][12][13][14] Many studies have suggested that these beneficial effects were primarily due to organosulfur compounds (e.g., S-allylcysteine and diallyl disulfide). 15,16) However, there have been few studies on the immunomodulatory effects of the bunching onion.…”