drug release article 10 priority journal 10 Animal 6 animal experiment 6 kinetics 6 prostaglandin 6 theophylline 6 Drug Carriers 4 Drug release 4 Gels 4 Norepinephrine 4 Polymers 4 Prostaglandins 4 Rats 4 Reaction kinetics 4 Scleroglucan 4 Solubility 4 Sympathetic Nervous System 4 endocrine system 4 hydrogel 4 in vitro study 4 indometacin 4 noradrenalin 4 radioisotope 4 rat 4 scanning electron microscopy 4 scleroglucan 4 solubility 4 steady state 4