several possibilities of increasing the effective half-life were investigated including ( i ) multiple intraperitoneal injections , ( ii ) concomitant administration of an inhibitor of glyoxalase i , ( iii ) administration of aldehyde-cysteine adducts , and ( iv continuous intravenous infusion . methylglyoxal ( 36 mg/kg i.p. , twice daily ) was slightly less effective in inhibiting the growth of the solid form of ehrlich carcinoma than a dose of 72 mg/kg ( inj . 1 ) ; 36 mg/kg ( inj . 2 ) 46.2 % compared to 51 % . the aldehyde was more effective aginst the ascitic form of the tumour , with 99.76 % inhibition of growth after giving 72 mg/kg twice daily for five days followed by 36 mg/kg for five days . the glyoxalase i inhibitor s- ( p-bromobenzyl ) -glutathione didnot significantly enhance the activity of methylglyoxal against the solid form of the tumour . nicotinamide ( 1 % w/v in the drink ) was similarily inactive . methylglyoxal in combination with nicotinamide was significantly more effect ( p less than 0.05 ) than methylglyoxal alone ( 36 mg/kg , twice daily ) in inhibiting the growth of the ascitic tumour . methylglyoxal-n-acetyl-l-cysteine was four times less toxic than methylglyoxalalone but was marginally less effective against the ascitic form of the tumour . doses of these adducts equivalent to 144 mg/kg per day of methylglyoxal were more effective p less than 0.05 ) than the optimal regime of methylglyoxal in inhibiting the solid tumour ( 67.5 % inhibition compared to 51 % ) .
C0010654
cysteine
C0001047
n-acetyl-l-cysteine