Serotonin (5-HT) and the rat's eye

Abstract

Serotonin (5-hydroxytryptamine, 5-HT) is a biogenic amine which has a multitude of more or less clearly established effects on peripheral vessels. It influences blood viscosity, platelet aggregation, and vasoconstruction and -dilatation, it enhances capillary permeability, it is the precursor of melatonin (a hormone with diurnal production in the eye). Because of these actions a role for serotonin in the development of glaucoma and diabetic retinopathy might be suspected. In a series of pilot studies on rats the effects of serotonin on the anterior and posterior segments of the eye were studied. Serotonin had marked influence on the retinal and choroidal vasculature. The optic disk seemed to be very sensitive to serotonin. Possibly it had an influence on the blood-retinal barrier. It caused transient cataracts, probably by decreasing the production of aqueous. It blocked tropicamin-induced mydriasis. The techniques and provisional results of measurement of serotonin in human aqueous are also described.

Antidepressants-a possibly risk factor for cataract development: a cross-sectional study

“…10,13 Cataractogenic potential of serotonin was observed in rat model with lens opacification and formation of cortical cataracts after injection of 1% solution of serotonin. 5 In the current study, maximum number of eyes had peripheral cortical cataract, which was visually non-significant but in concordance with the observation by Boerrigter et al 5 One of the postulates for lens opacification is serotonin interfering with lens metabolism, which compromises ciliary body and anterior chamber. The presence of β receptors in lens and role of cataractogenic properties of catecholamines 6 should be further investigated.…”

“…12 Animal studies have revealed the role of serotonin in different areas of eye. 5 A wide variety of serotonin receptors have been identified in the lens of animal models. 10,13 Cataractogenic potential of serotonin was observed in rat model with lens opacification and formation of cortical cataracts after injection of 1% solution of serotonin.…”

“…Selective serotonin reuptake inhibitors (SSRIs) are the third most prescribed class of drug in the world and are associated with cataract gastrointestinal bleeding and fractures. [4][5][6][7][8] Etminan and colleagues analyzed the data of 18,784 Quebec residents age more than ≥65 years old with cataract and compared their health records with 187,840 aged-matched controls without cataract. 9 They reported SSRIs having increased risk of cataract formation by about 15%.…”

“…10 In the animal studies, serotonin neurotransmitter has shown to play a vital role in transparency of the lens and can lead in formation of cortical cataracts. 5 The discovery of receptors for serotonin within the eye strongly suggests that 5-HT plays a functional role in the various ocular tissues. Serotonin inhibits the adenosine triphosphatase enzyme (ATPase) at the level of lens epithelium.…”

Evaluation of the Ocular Hypotensive Response of Serotonin 5-HT1A and 5-HT2 Receptor Ligands in Conscious Ocular Hypertensive Cynomolgus Monkeys

“…Serotonin (5-hydroxytryptamine; 5-HT) is also found in the aqueous humor of humans (Veglio et al, 1998) and other mammals (Boerrigter et al, 1992). These observations have generated considerable interest in the role that serotonin might have in aqueous humor dynamics and even whether 5-HT might be involved in the development of ocular hypertension and glaucoma.…”