Adenylate cyclase stimulation and ocular hypertension inhibition by forskolin analogs / 中华实验眼科杂志

ObjectiveForskolin （FSK） analogs，isoforskolin （isoF），deacetylforskolin（deaF），and 1-acetylforskolin（1-aF），extracted from Coleus forskohlii native to Yunnan，were assayed for their adenylate cyclase stimulating activities in vitro and for effects of two analogs on ocular hypertension （OHT） in water-loaded rabbits．MethodsAdenylate cyclase stimulation was determined by protein-binding method of radioimmunoassay，and intraocular pressure was monitored by pneumatonometer．ResultsIt showed that isoforskolin and forskolin stimulated adenylate cyclase in vitro with almost equal activity，deacetylforskolin with milder activity，and 1-acetylforskolin with little activity in vitro．1％ deaF and 1-aF suppressed rabbit OHT induced by water-loading for at least 3h，with the maximal inhibitory rates of 6.0，10.9% respectively．ConclusionThis study suggests that two foskolin analogs （isoforskolin，deacetylforskolin） possess adenylate cyclase stimulation activities in vitro；deacetylforskolin and 1-acetylforskolin suppress OHT induced by water-loading in rabbits．

Pharmacological Effects of Several Chemical Constituents from Coleus Forskohlii Native to Yunnan / 昆明医科大学学报

Recently,Coleus forskohlii has been found in Yunnan;isoforskolin and 1-acetylforskolin have been isolated from the ethyl acetate extract of the plant.The effects of these constituents on airway smooth muscle,intraocular pressure and platelet aggregation were studied. 1 On isolated guinea pig parenchymal strips,IC_(50)of both isoforskolin and ethyl acetate extract antagonizing histamine(1?g/ml)were 1.0?0.13(vehicle:60% PEG-400,n=9)or 0.9?0.10(DMSO,n=9),and 10.2?1.03(60%PEG-400,n=12)or5.5?1.39(DMSO,n=7) ?g/ml,respectively. 2 with in vivo ethly acetate extract either 50 mg/kg ip or 100 mg/kg ig to guinea pig prior to exposure to nebulized 0.4% histamine,the bronchospasm(convulsion)was effectively prevented(P