RESUMO
The bark of the cashew tree, Anacardium occidentale, is known to exert various therapeutic effects in the folklore medicine. However, there is little exiperimental evidence to substantiate these claims. West, Garvey and Ling in 1973 reported hypotensive action. Present investigations were carried out to find the possible mode of its hypotensive and anticurare effects. It is now well known that most of the clinically used antihypertensive drugs exert their pharmacotherapeutic effect via a common mode of action in spite of their different origins. Bhargava proposed that the central adrenergic, dopaminergic, cholinergic and tryptaminergic mechanisms in the central nervous system regulate the cardiovascular system, but the existence of such a central mechanism does not rule out the possibility of a peripheral component in the antihypertensive action of the drugs. The pathways followed by the central adrenergic and serotonergic nerves in the central nervous sytem are well suited for the regulation of the blood pressure. Most animals which received Anacardium occindentale showed an initial hypotensive response following the administration. This was marked and was not influenced by several experimental procedure or the drug pretreatments. The delayed hypotensive response occurred in most of the animals between 60 to 120 min after its administration and once set, remained below the basal level all throughout the duration of the experiment. The experimental manoeuvres and drug designs did not influence the delayed hypotensive response. The hypotensive action occurred in rats, cats and dogs and did not show any initial rise in blood pressure. (au)
