Cardiovascular Effects Induced by Linalool in Normotensive and Hypertensive Rats

Abstract

Linalool is a monoterpene alcohol and constituent of several Brazilian aromatic medicinal plants, popularly used against hypertension. Cardiovascular effects induced by linalool were evaluated. In normotensive rats, ()-linalool [1, 5, 10, and 20 mg/kg body weight (BW); intravenous (i.v.)]-induced hypotension was associated with tachycardia, which was attenuated by atropine (2 mg/kg BW) and N G -nitro-L-arginine methyl ester (20 mg/kg BW), but was not modifi ed after indomethacin (5 mg/kg BW) administration. In hypertensive rats, linalool [200 mg/kg BW; oral (v.o.)] reduced blood pressure without changing the heart rate. In intact rings of rat mesenteric artery precontracted with 10 μM phenylephrine, linalool (from 6.4 · 10 -6 to 6.4 · 10 -3 M) induced relaxations in a concentration-dependent manner [E max = (115  13)%] that were not changed after atropine administration [E max = (105  2)%], and were not different from those obtained in endothelium-denuded rings precontracted with phenylephrine [E max = (108  7)%] or 80 mM KCl [E max = (113  7)%] or tetraethylammonium incubation [E max = (105  12)%]. Linalool (1.9 · 10 -3 M) antagonized the contractions induced by CaCl 2 (3 · 10 -6 -10 -2 M) (maximal inhibition, 81%). Furthermore, linalool inhibited the contractions induced by 10 μM phenylephrine or 20 mM caffeine. In conclusion, these results demonstrate that linalool reduces blood pressure probably due to a direct effect on the vascular smooth muscle leading to vasodilation.

Endothelium- and smooth muscle-dependent vasodilator effects of Citrus aurantium L. var. amara: Focus on Ca2+ modulation

“…We found that neroli significantly decreased [Ca 2+ ] c and attenuated KCl-induced contraction, suggesting that neroli exerts its vasodilatory effect, at least in part, by inhibiting Ca 2+ influx. These findings are consistent with a previous study, which showed that linalool, the most abundant component of neroli, exerted an antagonizing effect on extracellular Ca 2+ -dependent contractions in mesenteric arteries [16].…”

“…However, since ruthenium red decreases store-operated Ca 2+ entry [21], it is more likely that neroli inhibits a RyR-dependent, storeoperated Ca 2+ entry pathway rather than directly affecting intracellular Ca 2+ release. Neroli essential oil and its main components, commonly used in foods and as a natural complement to standard therapies, are known to exert relaxation effects [16]. Mixed essential oils that contain neroli essential oils have been reported to decrease diastolic blood pressure in hypertensive subjects [22].…”

Linalool elicits vasorelaxation of mouse aortae through activation of guanylyl cyclase and K+ channels

“…LIN induced vasodilation in a dose‐dependent manner, a property associated with endothelial function. The finding that LIN dose‐dependently induced vasorelaxation is consistent with previous results showing that the vasorelaxant effect of LIN was not influenced by endothelium [15]. This study used mouse aortae, which are capacitance blood vessels, whereas the previous study used rat mesenteric arteries, which are resistance blood vessels.…”

Beneficial effects of celery (Apium graveolens) on metabolic syndrome: A review of the existing evidences

“…The effects of reducing BP were attributed to decrease in level of vascular tone factor II (angiotensin II; Chai, Tian, Li, Liu, & Wu, 2010). It has been revealed that treatment of normotensive and hypertensive rats with linalool (a compound in celery) caused the reduction of BP through the dilation of vascular smooth muscle (Anjos et al, 2013). Su et al demonstrated the antihypertensive effects of luteolin (a substance in celery) in spontaneous hypertensive rats in vivo models.…”