Beta-cell growth and mass are preserved in long-term syngeneic islet transplantation in streptozocin-induced diabetic Lewis rats.
We determined beta-cell replication and mass in basal and stimulated conditions in long-term transplanted islets. Three groups of streptozocin-induced diabetic Lewis rats were transplanted with 1,000 islets (500 islets under left and right kidney capsules). At 2 (Tx-2), 5 (Tx-5), or 9 (Tx-9) months after transplantation, one of the two grafts (basal) was harvested; 14 days later, the contralateral graft (stimulated) was also harvested. Normoglycemia was achieved and maintained in all transplanted rats, although the capacity to respond to a glucose challenge deteriorated slightly 9 months after transplantation. Beta-cell replication remained stable in Tx-2, Tx-5, and Tx-9 basal grafts and was similar to replication in a control group of nontransplanted rats (0.28 +/- 0.06%); replication increased in Tx-2 (0.90 +/- 0.23%, P < 0.05) and Tx-9 (0.72 +/- 0.09%, P < 0.05) stimulated grafts. Beta-cell mass in basal grafts was similar to the initially transplanted mass (1.24 +/- 0.06 mg) and increased in stimulated grafts in Tx-2 (1.91 +/- 0.38 mg, P < 0.05) and Tx-5 (1.73 +/- 0.27 mg, P = 0.01) groups, compared with basal grafts, and in Tx-2 and Tx-9 groups (1.92 +/- 0.30 mg, P < 0.05), compared with initially transplanted mass. Therefore, beta-cell replication and mass were preserved up to 9 months after syngeneic transplantation, and beta-cells maintained the capacity to respond to increased metabolic demand, suggesting that replication is not a limiting factor in the survival of transplanted islets.
Nácher
V
V
Laboratory of Diabetes and Experimental Endocrinology, C.S.U.B.-Hospital de Bellvitge, University of Barcelona, Spain.
Raurell
M
M
Merino
J F
JF
Aranda
O
O
Soler
J
J
Montana
E
E
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D002455:Cell Division; D003921:Diabetes Mellitus, Experimental / Q000097:blood / Q000601:surgery*; D007515:Islets of Langerhans / Q000166:cytology / Q000473:pathology*; D016381:Islets of Langerhans Transplantation / Q000473:pathology* / Q000502:physiology*; D007668:Kidney; D008297:Male; D051381:Rats; D011917:Rats, Inbred Lew; D012016:Reference Values; D013997:Time Factors; D016042:Transplantation, Heterotopic; D014185:Transplantation, Isogeneic
D001786:Blood Glucose