Shimoda N, Maitani Y, Machida Y, Nagai T
Department of Pharmaceutics, University of Hoshi, Tokyo Japan.
Biol Pharm Bull. 1995 May;18(5):734-9. doi: 10.1248/bpb.18.734.
The effects of dose, pH and osmolarity on the intranasal absorption of a recombinant human erythropoietin (rEPO) solution were studied in male Wistar rats. The intranasal administration of rEPO was evaluated by measuring percentage circulating reticulocytes of red blood cells on a stained blood smear (smear method), and also by measuring residual circulating reticulocyte counts using a microcell counter (sysmex method). Both results suggest that rEPO solution was absorbed through the nasal mucosa of rats without enhancers after a single intranasal administration. The pharmacological availabilities of rEPO after intranasal administration compared with intravenous administration were about 7% and 4%, when estimated by smear method and sysmex method, respectively. The pharmacological activity was enhanced in low pH and hypotonic mannitol solution.
