RESUMO
Aim To investigate the protective effects of dihydrolycorine on hypoxia/reoxygenation (H/R) injury in cultured neonatal rat cardiomyocytes. Methods The hypoxia/ reoxygenation injury model of cultured neonatal rat cardiomyocytes was developed. The cell livability, the activity of lactate dehdrogenase (LDH) and superoxide dismutase (SOD), and the content of malondialdehyde (MDA) were determined in the cultured neonatal rat cardiomyocytes injured by H/R. Results Compared with normal group, the cell livability and the SOD activity of model group were decreased respectively, whereas the activity of LDH and the content of MDA of model group were increased significantly (P
RESUMO
Dihydrolycorine(DL)HCI was produced semisynthetically from lycorine which is an alkaloid isolated from lycoris radiata Herb.The dose-response curves for phenylephrine iv to increase mean arterial pressure were shifted rightward by DL 40 mg/kg iv in anesthetized cats.The dose- response curves for phenylephrine iv to increase diastolic pressure were shift- ed rightward by DL iv in pithed rats:but DL didn't shift the dose-response curves of BHT_(920).In rat anococcygeal muscle,DL 3,10,30,100uM/L shifted cumulative dose-response curves of methoxamine rightward parallelly with pa2 value 6.35.In the isolated rabbit aortic ring,DL 10,30,100uM/L also shifted cumulative dose-response curves of methoxamine rightward parallelly with pA2 value 5.93.These results suggest that DL can block a-adrenoceptors.