[Effects of alpha 2-agonist apraclonidine on norepinephrine levels in the rat iris-ciliary body].
In an attempt to estimate the in vivo catecholamine level in rat iris-ciliary body, animals were sacrificed by microwave irradiation which rapidly inactivates metabolic enzymes. Catecholamine levels in the iris-ciliary body were determined by high-performance liquid chromatography with electrochemical detection. The norepinephrine level in rat iris-ciliary body per gram tissue protein was 3.56 +/- 0.22 micrograms/g (21.1 +/- 1.3 nmol/g)(mean +/- SEM, n = 7). Neither dopamine nor epinephrine were detected. A single instillation of 5 microliters of an 0.05% apraclonidine (alpha 2-agonist) to one eye of a rat increased the norepinephrine level in the iris-ciliary body by 7.7% one hour after administration (p less than 0.05).
Hiromatsu Eye Clinic, Ichihara, Japan.
S
S
Hiromatsu
M
M
Araie
K
K
Fujimori
D000316:Adrenergic alpha-Agonists / Q000494:pharmacology*; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D002924:Ciliary Body / Q000187:drug effects* / Q000378:metabolism; D003000:Clonidine / Q000031:analogs & derivatives* / Q000494:pharmacology; D007498:Iris / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D009638:Norepinephrine / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D000316:Adrenergic alpha-Agonists; C016986:apraclonidine; D003000:Clonidine; D009638:Norepinephrine