Day and night chronesthesy of 24,25(OH)(2)D-3, copper (II) and [Cu(II)-24,25(OH)(2)D-3] complex on renal and cerebral enzymatic activities in male hypophysectomized rats

In this study, we investigated the day and night periodic effects of 24,25( OH)(2)D-3, Copper (II) as CuCl2 and [Cu(II)-24,25(OH)(2)D-3] complex on cer ebral and renal alkaline phosphatase (APA) and gamma-glutamyl transpeptidas e (gamma-GT) activities in hypophysectomized (Hx) rats in which vitamin D-3 metabolism is disturbed. During the day and night, cerebral APA and gamma- GT activities were higher in Hx rats than in intact (I): rodents APA: -36% and 38% respectively; p <.01; gamma-GT: -19% and 29% respectively; p <.01) while renal markers levels were lowered (APA: -16% and 21% respectively; p <.05; gamma-GT: 11% and -31% respectively; p <.01). Hx rats were more sensi tive to secosterois effects at night. In both organs, the complex stimulate d mostly APA activity at night, and in our experimental conditions, it was more efficient on renal APA activity during the rodents active period. In c onclusion, the effects of 24,25(OH)(2)D-3, CuCl2 and [Cu(II)-24,25(OH)(2)D- 3] complex on APA and gamma-GT where quite different during day time and ni ght time and this could be explained on the basis of rythmic changes in bio logical susceptibility to chemical molecules in rats.