Do beta-adrenoceptors and serotonin 5-HT1A receptors have similar functions in the control of intraocular pressure in the rabbit?
Serotonin 5-HT1A-type and beta-adrenergic receptors have similar molecular characteristics, which explains why certain substances like propranolol have affinities for both receptor types. Activation of 5-HT1A receptors leads to a decrease in intracellular cAMP levels whereas the opposite occurs for beta-adrenergic receptors. Both 5-HT1A and beta-adrenergic receptors exist in the rabbit ciliary processes. Topical application of the 5-HT1A agonist, 8-hydroxydipropylaminotetralin (8-OH-DPAT) reduces intraocular pressure (IOP). beta-Antagonists are also known to reduce IOP. It is postulated that substances which have an affinity for 5-HT1A and/or beta-adrenergic receptors and lead to a reduction in intracellular cAMP levels in the ciliary processes diminish IOP.
Osborne
N N
NN
Nuffield Laboratory of Ophthalmology, University of Oxford, UK.
Chidlow
G
G
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D002924:Ciliary Body / Q000187:drug effects / Q000502:physiology; D007429:Intraocular Pressure / Q000187:drug effects / Q000502:physiology*; D011817:Rabbits; D011943:Receptors, Adrenergic, beta / Q000502:physiology*; D011985:Receptors, Serotonin / Q000502:physiology*; D017366:Serotonin Receptor Agonists / Q000494:pharmacology
D000319:Adrenergic beta-Antagonists; D011943:Receptors, Adrenergic, beta; D011985:Receptors, Serotonin; D017366:Serotonin Receptor Agonists