EFFECTS OF TIMOLOL AND ADRENALINE IN THE CONTROL OF CORNEAL NEOVASCULAR MOTILITY IN RATS
Corresponding author:
[email protected]
Received
12 January 2021
Revised
-
Accepted
04 March 2021
Available Online
15 March 2021
Abstract
THIS STUDY AIMED TO EVALUATE THE EXPR ESSION OF ALPHA OR BETA -TYPE ADRENERGIC RECEPTORS IN CORNEAL NEW BLOOD VESSELS. THE EXPERIMENTS WERE PERFORMED ON WISTAR RATS, IN WHICH A MODEL OF CORNEAL NEOVASCULARIZATION WAS OBTAINED BY REPEATED INJECTIONS OF KETAMINE (150MG/KG BODY WEIGHT), ADMINISTER ED INTRAPERITONEALLY. THE VARIATION OF THE EXTERNAL DIAMETER OF THE COR NEAL NEOFORMATION VESSELS WAS FOLLOWED, AT A TOTAL MAGNIFICATION OF APPROXIMATELY 400X, OVER 630 SECONDS. ADRENALINE PRODUCED STATISTICALLY SIGNIFICANT VASOCONSTRICTION IN THE CORNEAL NEOVESSELS VIA ALPHA -ADRENERGIC RECEPTORS. TIMOLOL PRODUCED STATISTICAL LY SIGNIFICANT VASODILATION, REGARDLESS OF THE DOSE ADMINISTERED, BY A MECHANISM INDEPENDENT OF BETA -ADRENERGIC RECEPTORS. TIMOLOL CAUSED VASODILATION IN A DOSE - DEPENDENT MANNER, THE VA SODILATION BEING INVERSELY PROPORTIONAL TO THE DOSE. FOLLOWING THESE RESULTS, WE CAN SAY THAT AT THIS LEVEL THERE ARE ALPHA -1 ADRENERGIC RECEPTORS, BUT WE CAN NOT EXCLUDE THE EXISTENCE OF BETA -ADRENERGIC RECEPTORS WHOSE STIMULATION PRODUCES VASODILATION.
Keywords
ADRENALINE
TIMOLOL
NEW CORNEAL BLOOD VESSELS
CORNEA
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