[Inhibitory effect and synergism of cernitin pollen extract on the urethral smooth muscle and diaphragm of the rat].
Inhibitory effects of cernitin pollen extract (CN-009), consisting of T-60 (a water-soluble extract) and GBX (an acetone-soluble extract) at a ratio of 20:1, were investigated in rat urethral smooth muscle and diaphragm. In the urethral smooth muscle, CN-009 (3.0 x 10(-4) approximately 3.0 x 10(-3) g/ml), T-60 and GBX (corresponding to CN-009) concentration-dependently inhibited the noradrenaline (NA, 10(-5) g/ml)-induced contraction. According to Bürgi's calculation, the inhibition by T-60 and GBX was synergistic. On the other hand, GBX inhibited the NA-contraction non-competitively and also inhibited the K+-contraction. In contrast, T-60 tended to inhibit competitively, but did not affect the K+-contraction. In the diaphragm, CN-009 (5.25 x 10(-3) approximately 2.1 x 10(-2) g/ml) concentration-dependently inhibited the nerve stimulation-induced twitch response. T-60 (corresponding to CN-009) showed no effect, while GBX slightly inhibited the twitch response. The effects of T-60 and GBX were synergistic. The inhibitory effects of CN-009 (2.1 x 10(-2) g/ml) and GBX (1.0 x 10(-2) g/ml) were specific against the nerve stimulation and were not antagonized by neostigmine (1.0 x 10(-5) g/ml). These results suggested that these effects were neither musculotropic nor competitive against ACh. In conclusion, CN-009 concentration-dependently inhibited the urethral contraction and the skeletal muscular twitch response. It was suggested that T-60 and GBX had different mechanisms and inhibited the response synergistically.
Nakase
K
K
Ome Research Laboratories, Tobishi Pharmaceutical Co., Ltd., Tokyo, Japan.
Takenaga
K
K
Hamanaka
T
T
Kimura
M
M
D000818:Animals; D003964:Diaphragm / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D009638:Norepinephrine / Q000037:antagonists & inhibitors; D010936:Plant Extracts; D011058:Pollen / Q000494:pharmacology*; D011188:Potassium / Q000037:antagonists & inhibitors; D051381:Rats; D011919:Rats, Inbred Strains; D012434:Secale; D014521:Urethra / Q000187:drug effects
D010936:Plant Extracts; C010070:cernilton; D011188:Potassium; D009638:Norepinephrine