We reasoned that any gains in activity from the increased concentration of substrate and lower DBS extraction volume are more than likely offset by reduced extraction efficiency of GLA due to the lack of sodium taurocholate
in the extraction buffer in the microfluidic protocol.
OATP-B, OATP-D, OATP-E) tended to have substrate affinity toward steroid sulfate, although OATP-E (an Oatp4a1 homolog) also had affinity toward taurocholate
Briefly, 5 g of each sample was cultured in 100 mL of prereduced brain-heart infusion (BHI) broth supplemented with cefoxitin (10 [micro]g/mL), cycloserine (250 [micro]g/mL), and taurocholate
5 [micro]g/min for 60 min in 140 mM NaCl containing 10mM sodium taurocholate
using a Harvard syringe pump.
0 gm % sodium taurocholate
to the standard (basal) commercial diet and daily feed consumption was recorded.
To the residue we added 15 [micro]L of 120 g/L sodium taurocholate
Merck, Darmstadt, Germany (all substances not specifically attributed to other source), Novartis, Grenzach-Wyhlen, Germany (Liquemin[R]), Sigma, Munchen, Germany (BSA, sodium taurocholate
and thiobarbituric acid) and Synopharma, Hamburg, Germany (butylhydroxytoluol).
We then added 240 [micro]L of an aqueous solution of sodium taurocholate
(120 g/L) and oleic acid (12 g/L) to the vial, vortex-mixed the sample until the residue dissolved, and then added 2.
Cyp7b1 is the hydroxylase involved in taurocholate
bile acid synthesis in mice (Russell 1999).