Degree Department

Degree Level

Toxicological Evaluation for the Ocular Administration of Tolrestat: An Aldose Reductase Inhibitor for the Treatment of Diabetes (open access)

Toxicological Evaluation for the Ocular Administration of Tolrestat: An Aldose Reductase Inhibitor for the Treatment of Diabetes

Aldose reductase inhibitors (ARI's) have been shown to attenuate or prevent several complications of diabetes in animals. Tolrestat is a potent and unique ARI from Ayerst Laboratories, New York, NY. The efficacy and toxicology of tolrestat via topical ocular administration was examined. Tolrestat effectively enhanced corneal reepithelialization and was efficacious in the prevention of cataracts in the streptozotocin-diabetic rat. Ocular tissues were examined by slit lamp biomicroscopy, scanning and transmission electron microscopy, and light microscopy. Liver and kidney tissue was also examined. The presence of tolrestat was confirmed in urine, feces, and eye specimens, and quantitated in serum. There was no evidence of local or systemic tolrestat induced toxicity. Tolrestat prevented cataract formation at less than one-third the reported oral dose and at approximately one-fiftieth the associated serum concentration in rats. ED-50 and TD-50 calculations indicate that tolrestat is a relatively safe drug by topical ocular administration.
Date: December 1987
Creator: Carney, Gerald R.
System: The UNT Digital Library
Cardiovascular Fetal Programming in Quail (Colinus virginianus), An Avian Comparative Model (open access)

Cardiovascular Fetal Programming in Quail (Colinus virginianus), An Avian Comparative Model

The consequences of early embryonic insults and how they affect subsequent life reflects the emerging concept of "fetal programming". The aim of this project is to study the effects of embryonic insults as they subsequently manifest themselves in adults, with emphasis on the heart and vasculature. My experiments establish that fetal programming operates on the bobwhite quail inducing similar changes as those observed in mammalians and other birds. The quail's fast development provides reliable data in a short period of time than other avian models (e.g. domestic chicken). Data on quail showed a correlation between egg mass and hatchling mass; where small eggs produce small hatchlings but a high mortality made it impractical as a stressor for this study. Hypoxia was used as a stressor during embryonic incubation, where it induced a low hatching weight in quail that was not observable in adult birds. Morphological measurements demonstrated an increased ventricular collagen content and reduced ventricular lumen in birds in adults incubated in hypoxia consistent with hypertension. The hematological analyzes showed few differences indicating organ remodeling instead of hematopoietic compensation. The assessment of vascular reactivity pointed out an impaired endothelium dependent relaxation commonly associated to hypertension in birds and mammals. Fetal …
Date: December 2016
Creator: Flores Santin, Josele R.
System: The UNT Digital Library