J. Sudo et al., KINETICS OF CD2-INJECTION OF CD-METALLOTHIONEIN-II( IN PLASMA, LIVER AND KIDNEYS AFTER SINGLE INTRAVENOUS), European journal of pharmacology. Environmental toxicology and pharmacology section, 270(2-3), 1994, pp. 229-235
To explore the kinetics of Cd2+ in the body, rats received a single in
travenous injection of CdCl2 or Cd-saturated metallothionein-II at 0.3
mg Cd/kg body weight. Cd2+ in the two agents was biexponentially elim
inated from plasma: rapidly in the first 5 min, and gradually later. C
ompared with CdCl2, Cd-saturated metallothionein-II showed lower Cd2concentrations in plasma during the first 30 min; larger values for pa
rameters concerning distribution of Cd2+, its total body clearance and
half-life time in the P phase. Cd2+ uptake in the liver was higher wi
th CdCl2, and, conversely, in the kidneys it was higher with Cd-satura
ted metallothionein-II. In Cd-saturated metallothionein-II, the renal
content of Cd2+ reached a maximum (8 mu g Cd2+/g tissue) on day 1, gra
dually decreasing thereafter; there was a higher area under the Cd2+ c
ontent-time curve, and a lower mean residence time of Cd2+; th, kidney
s showed severe necrosis and defluxion of proximal tubular cells at da
ys 1 and 5, although there were regenerative and reversion signs on da
y 5. These findings suggested that, in the case of Cd-saturated metall
othionein-II, Cd2+ being taken into the cells of proximal tubules was
excluded predominantly due to cellular death and the resultant defluxi
on.