The Thermodependence of Uterine Adenylate Cyclase in the Rat: Its Response to Fluoride and Decidual Stimulation PDF

Keywords

rat, uterus, zoology

Abstract

The thermodependence of adenylate cyclase (AC) from rat uteri during Day 4 (D4) of early pseudopregnancy after trauma was studied using radiochemical analysis. AC activity, measured at 4- 55 degree Celsius exhibited maximal activity between 30-35 degree Celsius. In this temperature range, the enzyme activity varied between 16.60 + - 0.76 and 17.00 +- 0.33 picomoles cAMP per min per mg protein. An Arrhenius plot of the enzyme activity showed a single slop between 4-30 degree Celsius. The energy activation (Ea) was 15.94 +- 0.31 Kcal mol-1 deg-1 and the Q10(20-30) was 2.04 +- 0.02. Incubation of the non traumatized uteri with 10mM sodium fluoride exhibited a temperature optimum similar to that of the traumatized uteri. In this temperature range, AC activity varied between 18.64 +- 0.50 and 1839 +- 0.47 picomoles cAMP per min per mg protein. An Arrhenius plot of the AC activity exhibited a single slop between 4-30 degree Celsius. The Q10 (20-30) was 2.38 +- 0.04. These data suggest a similarity between decidual stimulation and sodium fluoride with respect to the activation of uterine adenylate cyclase