  We report ac electrical transport in La0.7Sr0.3CoO3 and La1-xSrxMnO3 (x =
0.18- 0.5) as a function of temperature and frequency in H = 0 and 60 mT. Both
resistive (R) and reactive (X) components of impedance (Z = R+jX) were
measured. It is shown that a smooth decrease of the resistance around the Curie
temperautre in La0.7Sr0.3CoO3 transforms into an abrupt increase followed
closely by a peak in R with increasing frequency. Similar behavior in R was
also found in metallic compositions of the La-Sr-MnO3 series. The observed
anomaly at TC is suppressed by a small dc magnetic field of H = 60 mT which
rrsults in a huge ac magnetoreistance (= 30 % in manganite and =7 % in
cobaltite at f = 2 MHz). The anomaly in R in zero field is also accompanied by
a sudden incrases of X. While the ac magnetoresitance is negative as a function
of field from 100 Hz to 30 MHz, we show that the sign of X changes and a new
double peak structure develops in X for frequencies above 15 MHz.
