Free amino acids in the pre-retinal vitreous space. Effect of high potassium and nipecotic acid

doi:10.1016/S0014-4835(87)80008-8

Experimental Eye Research

Volume 44, Issue 2, February 1987, Pages 235-244

https://doi.org/10.1016/S0014-4835(87)80008-8 Get rights and content

The pre-retinal vitreous space of the eye of albino rabbits was perfused in vivo via a dialysis probe in order to measure the concentration of endogenous amino acids. Studies of isotope concentrations in the vitreal effluent following intracarotid injections of ³HOH and [¹⁴C]mannitol demonstrated that entrance of ³HOH into the dialysis probe occurred within a few minutes whereas [¹⁴C]mannitol was almost completely excluded. Among the amino acids, analysed with high-pressure liquid chromatography (HPLC), glutamine had a concentration similar to that in plasma and cerebrospinal fluid (CSF). Taurine was four times higher than in the CSF. Perfusion with 125 mm KCl media increased particularly the taurine and phosphoethanolamine content. Nipecotic acid, a potent inhibitor of γ-aminobutyric acid (GABA) uptake, increased GABA concentration over 60 times. In addition, it increased taurine levels by almost 10 times.

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^*: This work was supported by the Swedish Medical Research Council (grant no. 2226) and by grants from Torsten and Ragnar Söderbergs Foundation.

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Free amino acids in the pre-retinal vitreous space. Effect of high potassium and nipecotic acid*

Exp. Eye Res.

Brain Res.

Exp. Eye Res.

Exp. Eye Res.

Exp. Eye Res.

Neurosci. Lett.

The uptake index method applied to studies on the blood retinal barrier

Acta Physiol. Scand.

Neurotransmission in central nervous tissue. A study of isolated rabbit retina

J. Neurophysiol.

Stimulated release of (3H) alanine from the rabbit retina

Brain Res.

Retinal neurotransmitters: histochemical and biomedical studies

Light-evoked release of endogenous glycine into the perfused vitreous of the intact rat eye

Invest. Ophthalmol.

Drug prevention of blood-aqueous barrier disruption

Ophthalmic Rec.