Saiz J, Torres A, Martinez-Sierra R, Sanchez A
Eur J Pharmacol. 1986 Feb 18;121(2):161-6. doi: 10.1016/0014-2999(86)90486-3.
Effects on the alpha-adrenoceptor binding in the kidneys of DOCA-salt rats were examined after a 6 week treatment of once-daily injections of prazosin, a selective alpha 1-adrenoceptor blocker; yohimbine, a selective antagonist for alpha 2-adrenoceptors; and prazosin plus yohimbine. alpha 1-Receptor binding was decreased by prazosin, while alpha 2-receptor binding was increased by simultaneous administration of prazosin + yohimbine. Equilibrium dissociation constants (KD) for [3H]prazosin and [3H]yohimbine were not significantly different (between groups). Since these drugs can prevent the development of hypertension in DOCA-salt rats, the present data strongly suggests that selective alteration of alpha-receptor-mediated physiological responses is unrelated to decreased or increased binding site densities. The mechanism of hypertension prevention may involve changes in the coupling of receptors to postreceptor events.
在对去氧皮质酮盐（DOCA-盐）大鼠进行为期6周的每日一次注射治疗后，研究了选择性α1肾上腺素能受体阻滞剂哌唑嗪、α2肾上腺素能受体选择性拮抗剂育亨宾以及哌唑嗪加育亨宾对其肾脏α-肾上腺素能受体结合的影响。哌唑嗪可降低α1受体结合，而同时给予哌唑嗪和育亨宾可增加α2受体结合。[3H]哌唑嗪和[3H]育亨宾的平衡解离常数（KD）在各组之间无显著差异。由于这些药物可预防DOCA-盐大鼠高血压的发生，目前的数据强烈表明，α受体介导的生理反应的选择性改变与结合位点密度的降低或增加无关。预防高血压的机制可能涉及受体与受体后事件偶联的变化。
