We studied in vivo production of
taurine,
hypotaurine and
sulfate following subcutaneous administration of
L-cysteinesulfinate (CSA) to rats and mice. When 5.0 mmol/kg of
body weight of CSA was injected to rats, increased urinary excretions of
taurine,
hypotaurine and
sulfate in 24 h urine were 617, 52 and 1,767 micromol/kg, respectively. From these results together with our previous data,
sulfate production was calculated to be 1.6 times greater than
taurine production. Increased contents (micromol/g of wet tissue) over the control of
taurine and
hypotaurine in mouse tissues at 60 min after the injection of 5.0 mmol/kg
body weight of CSA were: liver, 3.5 and 9.9; kidney, 0.3 and 5.2; heart, 3.7 and 0.2; blood plasma, 0.4 and 0.2, respectively. Upon loading of
hypotaurine or
taurine, tissue contents of these
amino acids in liver and kidney increased greatly. Our results indicate that liver is the most active tissue for
taurine production, followed by kidney, and that external CSA,
hypotaurine and
taurine are easily taken up by these tissues.