OBJECTIVE: This study aimed to investigate the direct relaxant effects of anandamide and its possible mechanisms in isolated rat bladder and vas deferens tissues.
METHODS: Twenty-one adult male Wistar albino rats were used. Bladder and vas deferens (prostatic and epididymal portions) tissues were mounted in 10 mL of organ baths. Relaxation responses to anandamide were recorded at 3 and 10 μM concentrations. After the rest period, the procedures were repeated in the presence of cannabinoid (CB) and vanilloid receptor antagonists, various potassium channel blockers, cyclo-oxygenase, and nitric oxide synthase inhibitors. In different tissues to investigate the Ca2+-channel antagonistic effect of anandamide, concentration-response curves to CaCl2 were obtained in the absence and presence of anandamide.
RESULTS: Anandamide caused a significant relaxation response in the bladder and epididymal vas deferens tissues, but not in the prostatic portion. The effect of anandamide was antagonized in the presence of the CB1 antagonist AM251 or the non-selective potassium channel blocker tetraethylammonium in bladder tissue. In the epididymal vas deferens, anandamide significantly inhibited the calcium contraction responses, especially at high concentrations. The CB2 antagonist AM630 reversed this inhibition.
CONCLUSIONS: The results show that anandamide has a direct relaxant effect on the isolated rat bladder and epididymal vas deferens. Anandamide triggers different mechanisms in different types of tissues, and further studies are needed to elucidate the mechanism of action of anandamide.
目的:本研究旨在探讨anandamide对离体大鼠膀胱和输精管组织的直接松弛作用及其可能机制。
方法:使用21只成年雄性Wistar白化病大鼠。将膀胱和输精管(前列腺和附睾部分)组织固定在10mL器官浴中。在3和10μM浓度下记录对anandamide的松弛反应。休息后,在存在大麻素(CB)和香草素受体拮抗剂的情况下重复该程序,各种钾通道阻滞剂,环加氧酶,和一氧化氮合酶抑制剂.在不同组织中探讨Anandamide的Ca2+通道拮抗作用,在不存在和存在anandamide的情况下,获得了对CaCl2的浓度响应曲线。
结果:Anandamide引起膀胱和附睾输精管组织明显的松弛反应,但不是在前列腺部分。在膀胱组织中存在CB1拮抗剂AM251或非选择性钾通道阻断剂四乙基铵的情况下,anandamide的作用被拮抗。在附睾输精管,anandamide显著抑制钙收缩反应,特别是在高浓度。CB2拮抗剂AM630逆转了这种抑制。
结论:结果表明,anandamide对离体大鼠膀胱和附睾输精管有直接松弛作用。Anandamide在不同类型的组织中触发不同的机制,需要进一步的研究来阐明anandamide的作用机制。