Two new furostanol saponins from Tribulus terrestris.

Two new furostanol saponins were isolated from the fruits of Tribulus terrestris L. Their structures were established as 26-O-beta-D-glucopyranosyl-(25S)-5alpha-furost-20(22)-en-3beta,26-diol-3-O-alpha-L-rhamnopyranosyl-(1 --> 2)-[beta-D-glucopyranosyl-(1 --> 4)]-beta-D-galactopyranoside (1) and 26-O-beta-D-glucopyranosyl-(25S)-5alpha-furost-20(22)-en-12-one-3beta,26-diol-3-O-beta-D-galactopyranosyl-(1 --> 2)-beta-D-glucopyranosyl-(1 --> 4)-beta-D-galactopyranoside (2) on the basis of spectroscopic data as well as chemical evidence.

[Delta-opioid receptor mediates the cardioprotective effect of ischemic postconditioning].

Aim: To investigate the effect of 8-opioid receptors in the cardioprotection elicited by ischemic postconditioning and the underlying mechanism.

Methods: The isolated perfused hearts of male Sprague-Dawley rats were subjected to 30 min of global ischemia followed by 120 min of reperfusion. Formazan content of myocardium was measured spectrophotometrically, and the activity of lactate dehydrogenase (LDH) in the coronary effluent was measured.