[Central ocular hypotensive effect of noradrenaline].
We investigated the effects of topical and central administration of noradrenaline (NA) on the intraocular pressure (IOP) in pigmented rabbits. Unilateral instillation of NA (200 micrograms) produced no significant change in IOP. On the other hand, intracerebroventricular (ICV) administration of NA (0.01-1 micrograms) decreased IOP in both eyes in a dose-related fashion. The ocular hypotensive effect of NA was diminished by sympathectomy of the superior cervical sympathetic nerve or by ICV pretreatment with yohimbine hydrochloride 1-10 micrograms). These results suggest that the hypotensive effects of contrally administered NA might be mediated by alpha 2-adrenoceptor stimulation in the central nervous system.
Nakajima
K
K
Department of Ophthalmology, Showa University School of Medicine, Tokyo, Japan.
Ohno
J
J
Ueda
T
T
Inatomi
M
M
Koide
R
R
Kiuchi
Y
Y
Oguchi
K
K
Ueda
T
T
Uchida
E
E
Yasuhara
H
H
D000287:Administration, Topical; D000818:Animals; D003864:Depression, Chemical; D007276:Injections, Intraventricular; D007429:Intraocular Pressure / Q000187:drug effects*; D008297:Male; D009638:Norepinephrine / Q000008:administration & dosage / Q000494:pharmacology*; D009883:Ophthalmic Solutions; D011817:Rabbits
D009883:Ophthalmic Solutions; D009638:Norepinephrine