PMID- 10420121
OWN - NLM
STAT- MEDLINE
DCOM- 19990809
LR  - 20171101
IS  - 0030-3747 (Print)
IS  - 0030-3747 (Linking)
VI  - 31
IP  - 5
DP  - 1999
TI  - Retinal capillary changes in Otsuka Long-Evans Tokushima fatty rats 
      (spontaneously diabetic strain). Electron-microscopic study.
PG  - 358-66
AB  - The Otsuka Long-Evans Tokushima fatty (OLETF) rat is a spontaneously diabetic 
      strain with polyuria, polydipsia and mild obesity. The pathological features of 
      OLETF rats closely resemble those of patients with non-insulin-dependent diabetes 
      mellitus. The purpose of this study is to investigate the retinal capillary 
      changes in the OLETF rat and to confirm the valuability of the OLETF rat as the 
      model of diabetic retinal disease. One-month-old male OLETF rats and age- and 
      sex-matched Long-Evans Tokushima Otsuka (LETO) controls were supplied by Otsuka 
      Pharmaceutical Co. Ltd. (Tokushima, Japan). Body weight and blood sugar levels 
      were measured monthly. Their eyes were enucleated 14 months after birth. 
      Ultrathin sections were made and examined with a transmission electron 
      microscope. According to their location, two kinds of retinal capillaries were 
      differentiated: those in the nerve fiber layer (NFL) and those in the outer 
      plexiform layer (OPL). The image of each capillary was transferred to a computed 
      image analyzer, and basement membrane thickness and the ratio of the pericyte 
      area to total capillary cross-section area were determined. Corrosion casts of 
      retinal vessels were made and examined with scanning electron microscopy (SEM). 
      OLETF rats gained more weight than LETO rats from the beginning, and the 
      difference increased gradually with age. The blood sugar level of OLETF rats was 
      higher than that of LETO rats after 5 months of age. In the retinal capillaries 
      of 14-month-old OLETF rats, basement membranes were significantly thicker (OLETF: 
      209 +/- 51 nm in NFL, 132 +/- 23 nm in OPL; LETO: 118 +/- 28 nm in NFL, 79 +/- 14 
      nm in OPL), and the ratio of pericyte area to the capillary cross-section area 
      was significantly lower than that of the controls (OLETF: 0.131 +/- 0.92 in NFL, 
      0.111 +/- 0.102 in OPL; LETO: 0.288 +/- 0.142 in NFL, 0.198 +/- 0.136 in OPL). 
      The endothelial cell cytoplasm had degenerated. SEM examination of the vascular 
      corrosion cast of a 14-month-old OLETF rat showed caliber irregularity, 
      narrowing, tortuosity and loop formations of capillaries. The morphological 
      changes in the retinal capillaries of OLETF rats were similar to those seen in 
      diabetic patients. The OLETF rat may be a useful animal model for the study of 
      ocular diabetic complications in humans.
FAU - Miyamura, N
AU  - Miyamura N
AD  - Department of Ophthalmology, Nagasaki University School of Medicine, Nagasaki, 
      Japan.
FAU - Bhutto, I A
AU  - Bhutto IA
FAU - Amemiya, T
AU  - Amemiya T
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Switzerland
TA  - Ophthalmic Res
JT  - Ophthalmic research
JID - 0267442
SB  - IM
MH  - Animals
MH  - Capillaries/ultrastructure
MH  - Corrosion Casting
MH  - Diabetes Mellitus, Type 2/genetics/*pathology
MH  - Diabetic Retinopathy/genetics/*pathology
MH  - Disease Models, Animal
MH  - Male
MH  - Microscopy, Electron, Scanning
MH  - Rats
MH  - Rats, Long-Evans
MH  - Retinal Vessels/*ultrastructure
EDAT- 1999/07/27 00:00
MHDA- 1999/07/27 00:01
CRDT- 1999/07/27 00:00
PHST- 1999/07/27 00:00 [pubmed]
PHST- 1999/07/27 00:01 [medline]
PHST- 1999/07/27 00:00 [entrez]
AID - 55559 [pii]
AID - 10.1159/000055559 [doi]
PST - ppublish
SO  - Ophthalmic Res. 1999;31(5):358-66. doi: 10.1159/000055559.