AIM: To study the mechanism involved in the potentially beneficial effect of ultra low dose aspirin (ULDA) in prehepatic portal hypertension, rats were pretreated with selective COX 1 or 2 inhibitors (SC-560 or NS-398...AIM: To study the mechanism involved in the potentially beneficial effect of ultra low dose aspirin (ULDA) in prehepatic portal hypertension, rats were pretreated with selective COX 1 or 2 inhibitors (SC-560 or NS-398 respectively), and subsequently injected with ULDA or placebo. METHODS: Portal hypertension was induced by portal vein ligation. Platelet activity was investigated with an in-vivo model of laser induced thrombus production in mesenteric circulation and induced hemorrhagic time (IHT). Platelet aggregation induced by ADP and dosing of prostanoid products 6-keto-PGF1α, TXB2, PGE2 and LTB4 were also performed. RESULTS: The portal hypertensive group receiving a placebo showed a decreased in vivo platelet activity with prolonged IHT, an effect that was normalized by ULDA. SC-560 induced a mild antithrombotic effect in the normal rats, and an unmodified effect of ULDA. NS-398 had a mild prothrombotic action in portal hypertensive rats, similar to ULDA, but inhibited a further effect when ULDA was added. An increased 6-keto-PGF1α was observed in portal hypertensive group that was normalised after ULDA administration. TXA2 level after ULDA, remained unchanged. CONCLUSION: These results suggest that the effect of ULDA on platelet activity in portal hypertensive rats, could act through a COX 2 pathway more than the COX 1, predominant for aspirin at higher doses.展开更多
For the first time it is shown that psychotropic action of acetylsalicylates at various doses is manifested as a nonmonotonic dependence having its peaks at therapeutic and ultra-low dose zones. It is discovered that ...For the first time it is shown that psychotropic action of acetylsalicylates at various doses is manifested as a nonmonotonic dependence having its peaks at therapeutic and ultra-low dose zones. It is discovered that development of effects of aspirin resembles that of acetylsalicylate zinc. Acetylsalicylate cobalt at extremely low doses zone showed the highest antidepressant activity, demonstrating toxicity at high doses. Generally, it is revealed that the use of aspirin and its salts at high doses range causes maximum psychotropic effects development, usually accompanied by side-effects. Therefore, aspirin, acetylsalicylate cobalt and zinc at extremely low doses are recommended for further study as psychotropic medications.展开更多
文摘AIM: To study the mechanism involved in the potentially beneficial effect of ultra low dose aspirin (ULDA) in prehepatic portal hypertension, rats were pretreated with selective COX 1 or 2 inhibitors (SC-560 or NS-398 respectively), and subsequently injected with ULDA or placebo. METHODS: Portal hypertension was induced by portal vein ligation. Platelet activity was investigated with an in-vivo model of laser induced thrombus production in mesenteric circulation and induced hemorrhagic time (IHT). Platelet aggregation induced by ADP and dosing of prostanoid products 6-keto-PGF1α, TXB2, PGE2 and LTB4 were also performed. RESULTS: The portal hypertensive group receiving a placebo showed a decreased in vivo platelet activity with prolonged IHT, an effect that was normalized by ULDA. SC-560 induced a mild antithrombotic effect in the normal rats, and an unmodified effect of ULDA. NS-398 had a mild prothrombotic action in portal hypertensive rats, similar to ULDA, but inhibited a further effect when ULDA was added. An increased 6-keto-PGF1α was observed in portal hypertensive group that was normalised after ULDA administration. TXA2 level after ULDA, remained unchanged. CONCLUSION: These results suggest that the effect of ULDA on platelet activity in portal hypertensive rats, could act through a COX 2 pathway more than the COX 1, predominant for aspirin at higher doses.
文摘For the first time it is shown that psychotropic action of acetylsalicylates at various doses is manifested as a nonmonotonic dependence having its peaks at therapeutic and ultra-low dose zones. It is discovered that development of effects of aspirin resembles that of acetylsalicylate zinc. Acetylsalicylate cobalt at extremely low doses zone showed the highest antidepressant activity, demonstrating toxicity at high doses. Generally, it is revealed that the use of aspirin and its salts at high doses range causes maximum psychotropic effects development, usually accompanied by side-effects. Therefore, aspirin, acetylsalicylate cobalt and zinc at extremely low doses are recommended for further study as psychotropic medications.