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Artemisinin 1, dihydro-epideoxyarteannuin B 2 and deoxyartemisinin 3 were isolated from the sequiterpene lactone-enriched fraction obtained from the crude ethanolic extract of Artemisia annua L. These compounds were tested on ethanol and indomethacin-induced ulcer models. Compound 1 did not afford cytoprotection under the experimental models tested. Only compounds 2 and 3 decreased the ulcerative lesion index produced by ethanol and indomethacin in rats. These compounds did not demonstrate antiulcerogenic activity when tested on the ethanol-induced ulcer model, with previous administration of indomethacin, suggesting that the antiulcerogenic activity is a consequence of prostaglandin synthesis increase.

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The resulting enriched sesquiterpene lactone fraction and the crude ethanol extract of Artemisia annua L. aerial parts, showed antiulcerogenic activity when administered orally, on the indomethacin induced ulcer in rats. The sesquiterpene lactone fraction yielded three different polarity fractions on column chromatography as follows: non-polar, medium polarity and polar fraction, When submitted to the same indomethacin-induced ulcer in rats they resulted in different levels of inhibition of the ulcerative lesion index. The participation of nitric oxide was evaluated on an ethanol-induced ulcer model which had a previous administration of L-NAME, a NO-synthase inhibitor. Under these conditions, the medium polarity fraction maintained the antiulcerogenic activity, suggesting that nitric oxide could not be involved in the antiulcerogenic activity. When the animal groups were treated with N-ethylmaleimide, an alkylator of sulphhydryl groups, using the same experimental model, the medium polarity fraction maintained its antiulcerogenic activity, suggesting that the pharmacological mechanism is not related to non-protein sulphydryl compounds. On the ethanol-induced ulcer with previous indomethacin treatment, the medium polarity fraction lost its antiulcerogenic activity indicating that the active compounds of Artemisia annua L. increase the prostaglandin levels in the gastric mucosa. This hypothesis was reinforced by an increase of adherent mucus production by the gastric mucosa, produced by the medium polarity fraction on the hypothermic restraint stress induced ulcer model.

The resulting enriched sesquiterpene lactone fraction and the crude ethanol extract of Artemisia annua L. aerial parts, showed antiulcerogenic activity when administered orally, on the indomethacin induced ulcer in rats. The sesquiterpene lactone fraction yielded three different polarity fractions on column chromatography as follows: non-polar, medium polarity and polar fraction, When submitted to the same indomethacin-induced ulcer in rats they resulted in different levels of inhibition of the ulcerative lesion index. The participation of nitric oxide was evaluated on an ethanol-induced ulcer model which had a previous administration of L-NAME, a NO-synthase inhibitor. Under these conditions, the medium polarity fraction maintained the antiulcerogenic activity, suggesting that nitric oxide could not be involved in the antiulcerogenic activity. When the animal groups were treated with N-ethylmaleimide, an alkylator of sulphhydryl groups, using the same experimental model, the medium polarity fraction maintained its antiulcerogenic activity, suggesting that the pharmacological mechanism is not related to non-protein sulphydryl compounds. On the ethanol-induced ulcer with previous indomethacin treatment, the medium polarity fraction lost its antiulcerogenic activity indicating that the active compounds of Artemisia annua L. increase the prostaglandin levels in the gastric mucosa. This hypothesis was reinforced by an increase of adherent mucus production by the gastric mucosa, produced by the medium polarity fraction on the hypothermic restraint stress induced ulcer model.

Objective:The purpose of this study was to examine the degree of contribution from the vertebrobasilar and carotid systems to the origin of the PCA in fetal autopsy brains of last trimester of pregnancy and to compare with published data on the configuration of adult and fetal brains in a population of Sri Lankan origin.Materials and Methods:The external diameter of the PcomA, pre-communicating part (P1), and the post-communicating part (P2) of posterior cerebral artery (PCA) of 34 fetal brain in the last trimester of pregnancy (30 to 40 weeks of gestation) was measured using a stereomicroscope equipped with a micrometer calibrator.Results:The blood supply to the occipital lobe mainly via the PCA was seen in 25 (59%) of fetal brains as compared to that in the literature 220 (93%) in adults brains and the blood supply to the occipital lobe mainly via the internal carotid artery (ICA) was seen in 16 (34%) of fetal brains as compared to 25 (7%) of adults brains (P < 0.0001), transitional configuration where the PcomA is equal in diameter to P1 segment of the PCA was seen in 5 (7.4%) of fetal brains and 8 (2%) of adults brains.Conclusions:The present study reveals that from the newborn to the adult there is shift from carotid system to the vertebrobasilar system, this justifies further studies on different racial and geographic regions which may give a clearer picture about the cerebral hemodynamics from childhood to adult.

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