Prostaglandin F_2α Binding to Bovine Ocular and Synthetic Melanins in Vitro

Abstract

The binding of 3H-prostaglandin F2 alpha to bovine iris and synthetic melanin was studied in vitro using a ligand binding assay. Prostaglandin F2 alpha was reversibly bound to both types of melanin. The binding was saturable and the Scatchard analysis revealed the existence of at least two binding sites with the corresponding K(D) values of 3.71 nM and 1.99 microM for natural and 4.99 nM and 0.19 microM for synthetic melanin, respectively. The high affinity Bmax values were 3.4 nM/g for natural and 2.5 nM/g for synthetic melanin. The dissociation of prostaglandin F2 alpha from melanin after dilution of the complex was rapid and uniform.

Latanoprost Stimulates Eumelanogenesis in Iridial Melanocytes of Cynomolgus Monkeys

“…The tissue was kept frozen at about −20°C until analyzed for melanin. In other experiments, iridial tissues, obtained as above from untreated animals, were fractionated by ultracentrifugation on a saccharose gradient as described (10), and the isolated melanosomes were subjected to chemical analysis.…”

Influence of Melanin Characteristics on Drug Binding Properties

“…Several comparative studies have examined drug binding to melanins from different sources. ,,, For instance, melanin binding parameters for memantine were determined using synthetic, Sepia, and bovine melanin; differences in binding affinity and maximum binding capacity were observed between the different melanin types . On the other hand, Cheruvu et al studied the binding of celecoxib to S.…”