Objective  To study the reconstruction and secretory function of the grafts after adrenal transplantation using fetal rats as donors.   Methods  Thirty adult SD rats randomly received sham operation (group A)

excision of bilateral adrenals (groups B

C

D and E)

and additionally adrenal transplantation in groups C

D and E using fetal rats aged 16

18 and 20 days respectively as donors.   Results  The weight of  group A got down to the lowest at the 3rd week

and restored to the preoperation level at the 4th week after sham operation. The weight of group B gradually rose up within 4 weeks. The weight of groups C and D rose up in the first 2 weeks

then down. The weight of group E rose slowly within the first 3 weeks

then down. The serum level of corticosterone decreased sharply in group B after operation

while that of groups C

D and E went down obviously in the first 2 weeks

then up

but that in group C was significantly lower than that in groups D and E. Microscopically

we found the capsule of allografts thicken and underneath many proliferative cells and well-constructed glomerular and fascicular zone 4 weeks after operation.   Conclusion  After transplantation

the fetal adrenal could survive and reconstruct well

and its secretory function gets better gradually. The graft from the elder donor is better than that from the younger in reconstruction and secretory function

but shows no obvious difference in immunological rejection.