Physiology
Condensed Ocular Biochemistry
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Get access| Structure | Sodium | Potassium | Other |
| Corneal epithelium | Low 70 mmol/L | High 140 mmol/L | |
| Corneal stroma | High 170 mmol/L | Low 20 mmol/L | |
| Aqueous | Low (slightly) | Similar | 99% water High chloride High lactate High ascorbate Low bicarbonate Low glucose Low calcium Low protein |
| Lens | Low 20 mmol/L | High 25 mmol/L | High glutathione 66% water Low chloride Low glucose |
| Vitreous | High (slightly) | Similar | NB: same as aqueous |
| CSF | Similar | Similar (slightly lower) | High chloride High hydrogen ions Low protein Low calcium Low glucose |
| compared to serum |
Glycosaminoglycans
- Long chains of disaccharides
- Form proteoglycans when combined with proteins
- Hyaluronic acid predominates in the vitreous
- Keratan sulphate predominates in the cornea