Effects of an extract of Ginkgo biloba on rabbit isolated aorta

Effects of an Extract of Ginkgo biloba on the 3′,5′‐Cyclic AMP Phosphodiesterase Activity of the Brain of Normal and Triethyltin‐Intoxicated Rats

“…A standardized extract from the leaves of Ginkgo biloba (EGB) is currently widely used for the treatment of ischemic cerebral diseases, and several clinical studies have demonstrated its beneficial effect against various neurological disorders (Safi and Galley, 1977;Heiss and Zeiler, 1978;Tea et al, 1979). The pharmacological activity profile of EGB has also been described (for review, see Anton, 1977;Chatterjee and Trunzler, 198 1;Auguet et al, 1982;Auguet and Clostre, 1983;Agnoli et al, 1984).…”

“…Although some proposals have been made (Anton, 1977;Auguet et al, 1982;Etienne et al, 1982;Vilain et al, 1982;Auguet and Clostre, 1983), the mechanisms through which EGB exerts its beneficial effects are not yet clearly defined. One of the important observations made with EGB is that it affords protection against cerebral edema and other neurotoxic symptoms associated either with experimental microem-bolization induced by intracarotid injection of microspheres (Larsen et al, 1978;Rapin and Le Poncin-Lafitte, 1979;Le Poncin-Lafitte et al, 1980) or with triethyltin (TET) (Gabard and Chatterjee, 1980;Chatterjee and Gabard, 1984;Karcher et al, 1984) and hexachlorophene (Chattejee and Gabard, 1984) intoxications.…”

Phytochemicals and Antioxidants

“…In some cases, the ginkgo leaf extracts out-performed modern drugs for mental insufficiency, e.g., ergot alkaloids and vincamine. Some researchers concluded that the effects were mediated by catecholamine release (Auguet, De Feudis, and Clostre 1982;Auguet et al 1982;Brunello et al 1985), and by calcium ion flux over smooth muscle cell membranes (Auguet and Clostre 1983). These effects share some similarities with those of theophylline and papaverine.…”

“…But before recent decades, traditional Chinese herbal medicine rarely used ginkgo leaves for treating occlusive circulatory disorders and other medical conditions. Many European studies reported that extracts of ginkgo leaves enhanced brain circulation (Larsen, Dupeyron, and Boulu 1978;Rapin and Le Poncin-Lafitte 1979;Le Poncin-Lafitte, Rapin, and Rapin 1980), had peripheral vasodilative and hypotensive effects (Auguet, De Feudis, and Clostre 1982), increased the brain's tolerance to hypoxia (Le Poncin-Lafitte et al. 1982;Schaffler and Rech 1985), reduced venule thrombi formation (Borzeix, Labos, and Hartl 1980), increased venular and capillary blood flow and reactivated capillaries that were formerly shut off from circulation (Piovella 1973), protected retinal injury from free radicals (Clairambault et al 1986), rendered the erythrocyte membrane more resistant to hemolysis (Etienne et al 1982), enabled patients with peripheral arterial insufficiency to walk longer distances and improved their blood flow through the lower limbs (Bauer 1984), and improved cerebral hemodynamics and ameliorated mental deficit (Gessner, Voelp, and Klasser 1985;Haan et al 1982;Eckmann and Schlag 1982).…”

Neuroprotective Effects of Ginkgo biloba Extract

“…There is some experimental evidence of the potency of EGb 761 to induce the release of catecholamines from their intracellular stores (17,18), thereby acting as an indirect sympathomimetic agent. This hypothesis was supported by the findings that EGb 761 forced the contractile effect of noradrenaline in isolated vessels (17) and that cocaine, which stabilizes the cellular membrane, diminished the constrictive effect of EGb 761 by inhibiting the release of the catecholamines (18). In addition, an increase in the levels of biogenic monoamines in certain brain regions (19) and an inhibition of monoaminoxidase by EGb 761 (20) were found.…”