PROBLEM TO BE SOLVED: To provide a method for evaluating the risk (safety range) of difficulty of urination by using the urinary bladder capacity increasing action (drug effect) of a medicament having antimuscarinic effects and the action thereof on urination function (side effect) when using the same kind of animals.SOLUTION: In a method for evaluating the risk of difficulty of urination, a method for evaluating the urinary bladder capacity increasing action of a test medicament by administering the test medicament to a rat and measuring urinary bladder capacities thereof is combined with a method for evaluating the action of the test medicament on urination function. The method for evaluating the action of the test medicament on urination function includes the following steps of: (a) measuring the maximum urine flow amount of a urethral obstruction model in the non-administration of the test medicament obtained by injecting α1 agonist to a female rat by a flow-meter (b) measuring the maximum urine flow amount when administering the test medicament to the urethral obstruction model by the flow-meter and (c) calculating change in the maximum urine flow amount measured in the step (a) and the maximum urine flow amount measured in the step (b).COPYRIGHT: (C)2015,JPO&INPIT【課題】同種の動物を使用した、抗ムスカリン様作用を有する薬物の膀胱容量増大作用(薬効)及び排尿機能への作用(副作用)を用いて排尿機困難のリスク(安全域)の評価方法を提供する。【解決手段】ラットに被験薬物を投与し、膀胱容量を測定する被験薬物の膀胱容量増大作用を評価する方法と以下の(a)~(c)の工程を含む排尿機能への被験薬物の作用の評価方法とを組み合わせることを特徴とする排尿困難リスクの評価方法。(a)雌性ラットにα1アゴニストを注入して得られる尿道閉塞モデルの被験薬物非投与時の最大尿流量を流量計(フローメーター)により測定する工程、(b)上記尿道閉塞モデルに被験薬物投与した際の最大尿流量を流量計により測定する工程、(c)(a)で測定した最大尿流量と(b)で測定した最大尿流量の変化を算出する工程。【選択図】図1
