SPRING TIME AND FALL TIME EFFECTS OF 1,25-DIHYDROXYVITAMIN D-3 COBALT(II) AND [COCL2(1,25(OH)(2)D-3)(4)] COMPLEX ON RENAL AND CEREBRAL ENZYMATIC MARKERS IN RATS

In this work, we studied the chronesthesia of 1,25-dihydroxyvitamin D- 3 (1,25(OH),D,), cobalt (II) chloride and of the complex [CoCl2(1,25(O H)(2)D-3)(4)]. The study was carried out in spring and autumn on AP an d gamma-GT activities in brain and kidney of rats during the rodents' active period. In rat brain, in both seasons, 1,25(OH)(2)D-3 enhanced AP activity by 59 % in spring and 21 % in autumn and gamma-GT by 39 an d 35 % respectively. Cobalt (II) stimulated AP activity by 34 and 29 % respectively. The complex was mainly active on gamma-GT activity (70 and 36 %) showing a synergic effect on gamma-GT activity in June. In r at kidney, during spring, the induction of AP activity for 1,25(OH)(2) D-3, cobalt (II) chloride and their complex was, respectively 21, 18 a nd 12 %. The gamma-GT activity was not modified during this period, wh ereas in autumn, it was inhibited by - 33, - 50 and - 28 %. The AP act ivity in autumn was not altered. We conclude that the effects on the t wo enzymatic markers of the three compounds 1,25(OH)(2)D-3, cobalt (II ) chloride and [CoCl2(1,25(OH)(2)D-3)(4)] are quite different in Sprin g and Autumn, and this is explained on the basis of chronesthesia.