Figure 25. Semi logarithmic plots of the amounts ( y g) of buprenorphine (1)
excreted in urine per min ( yg/min) plotted against t-mid, the mid point of the
urine collection interval for the 1.6369 mg/kg IV bolus dose of buprenorphine in
dog B, Study #2, in accordance with the equation:
log AU/A t = -(k'/2.303) t-mid + intercept
The insets represent the data fitted into two separate linear segments as per the
above equation. The estimated rate constants were 0.019/min (a, half-life = 37
min) and 0.0011/min (b, half-life = 622 min). Note the correspondence of these
rate constants with those reported in fig. 5 for the plasma data of this dog
(Study #2, Table 2).