Purchase this article with an account.
Clemens Strohmaier, Christian Runge, Barbara Bogner, Andrea Trost, Falk Schrödl, Günther Grabner, Herbert A. Reitsamer; The Effect Of Adenosine On The Optic Nerve Head Blood Flow In Rabbits. Invest. Ophthalmol. Vis. Sci. 2012;53(14):6850.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
To investigate the effect of different doses of adenosine on optic nerve head blood flow in New Zealand rabbits, using a novel, non-invasive Laser Doppler Flowmetry instrument.
White New Zealand rabbits (2-3 kg, n = 12) were anesthetized with Pentobarbital Sodium (50 mg/kg i.v.) and respired with room air. The mean arterial pressure (MAP) and the intraocular pressure (IOP) were measured through cannulation of the central ear artery and the vitreous body, respectively. Non-invasive Laser Doppler Flowmetry was used to measure optic nerve head blood flow continuously. In group 1, the dose-response characteristics at baseline MAP was investigated, adenosine was applied intravenously at different rates of 2,5mg/kg/h, 5mg/kg/h, 7,5mg/kg/h und 10mg/kg/h. In group 2, MAP was manipulated mechanically with occluders placed around the aorta and vena cava and thus, ocular perfusion pressure was changed over a wide range. Pressure-flow relationships were measured at control and in response to i.v. administration of adenosine at 5 mg/kg/h.
Adenosine caused a statistically significant increase in blood flow by 36,1 ± 3,9 % at a rate of 5 mg/kg/h. At the higher doses of 7,5 and 10 mg/kg/h blood flow increased further by 79,2 ± 8,7 % and 95,8 ± 6,9 % from baseline. The dose of 2,5 mg/kg/h had no significant effect on any measured parameter. The high dose (10 mg/kg/h) caused a significant reduction of the mean blood pressure by 11,3 ± 3,2 %. In addition, the doses of 5, 7,5 and 10 mg/kg/h increased the IOP significantly by 22,1 ± 2,3 % , 34,6 ± 7,5 % and 33,2 ± 9,1 %. Adenosine at 5 mg/kg/h caused a significant upward shift of the pressure-flow relationship.
A concentration dependent vasodilation through adenosine in the optic nerve head was found. These results are in good accordance with the literature and previously published data from our group with other measurement techniques.
This PDF is available to Subscribers Only