Jie K, van Brummelen P, Vermey P, Timmermans P B, van Zwieten P A
Eur J Clin Pharmacol. 1987;32(2):115-20. doi: 10.1007/BF00542182.
The influence of treatment with the calcium entry blockers PY 108-068 (PY) and PN 200-110 (PN) on alpha 1- and alpha 2-adrenoceptor mediated vasoconstriction has been investigated in the forearms of hypertensive patients. Changes in forearm vascular resistance (FVR) in response to the intra-arterial infusion of drugs were determined at the end of a placebo period and after 2-4 weeks of treatment with PY or PN. The drugs used were the selective agonists methoxamine (alpha 1) and B-HT 933 (alpha 2). During placebo, basal FVR was dose-dependently increased by methoxamine and B-HT 933. Basal blood pressure was lowered during PN but not during PY. Treatment with the calcium entry blockers did not influence the effect of methoxamine, but the vasoconstriction induced by B-HT 933 was attenuated by both of the calcium entry blockers. These results confirm the findings in animal studies that calcium entry blockers preferentially inhibit the alpha 2-adrenoceptor mediated vasoconstriction induced by selective agonists.
在高血压患者的前臂中，研究了钙通道阻滞剂PY 108 - 068（PY）和PN 200 - 110（PN）对α1和α2肾上腺素能受体介导的血管收缩的影响。在安慰剂期结束时以及用PY或PN治疗2 - 4周后，测定前臂血管阻力（FVR）对动脉内输注药物的反应变化。所用药物为选择性激动剂甲氧明（α1）和B - HT 933（α2）。在安慰剂期间，甲氧明和B - HT 933使基础FVR呈剂量依赖性增加。PN治疗期间基础血压降低，但PY治疗期间未降低。钙通道阻滞剂治疗不影响甲氧明的作用，但两种钙通道阻滞剂均减弱了B - HT 933诱导的血管收缩。这些结果证实了动物研究中的发现，即钙通道阻滞剂优先抑制选择性激动剂诱导的α2肾上腺素能受体介导的血管收缩。
