Middeke M, Reder S, Holzgreve H
Medizinische Poliklink, Klinikum Innenstadt, Lugwig-Maximilians-Universität, München, Germany.
Blood Press. 1994 May;3(3):189-92. doi: 10.3109/08037059409102251.
Beta-adrenoceptors on lymphocytes are acutely increased after dynamic exercise in normotensive subjects, but not in hypertensives. It was thus of interest to evaluate the acute regulation of the lymphocyte beta-adrenoceptor-adenylate-cyclase-cAMP-system (BAAS) in patients with primary hypertension during dynamic stress after acute beta-blockade. Density and affinity of beta 2-adrenoceptors, and intracellular cAMP concentrations (baseline and isoprenaline stimulated values) were measured on the peripheral mononuclear cells in 8 male patients with primary hypertension before and immediately after dynamic exercise on a bicycle (50-200 W) at baseline and after acute beta-blockade (2 h following 100 mg atenolol). Dynamic exercise causes no significant changes in receptor density and affinity, nor in basal cAMP values. After acute beta-blockade the dynamic stress-induced rise in mean arterial blood pressure was significantly (p < 0.01) reduced from 33 to 24 mmHg, and beta-adrenoceptor density significantly (p < 0.05) increased from 1320 to 2102 molecules/cell, whereas affinity remained unchanged. Baseline and stimulated cAMP concentrations increased significantly (p < 0.05) from 5.3 to 7.0 and from 2.1 to 3.5 pmol/10(6) cells, respectively. These findings suggest that in primary hypertension the regulation of the beta 2-adrenoceptor-adenylate-cyclase-cAMP-system is impaired on exercise and can be normalised by acute beta-blockade. Since atenolol predominantly blocks beta 1-adrenoceptors, the observed normalisation of the lymphocyte BAAS may reflect only an unspecific effect of antihypertensive therapy per se.
血压正常的受试者在进行动态运动后，淋巴细胞上的β-肾上腺素能受体急剧增加，但高血压患者则不然。因此，评估急性β受体阻滞剂治疗后，原发性高血压患者在动态应激期间淋巴细胞β-肾上腺素能受体-腺苷酸环化酶-cAMP系统（BAAS）的急性调节情况具有重要意义。在8名男性原发性高血压患者中，于基线状态以及急性β受体阻滞剂治疗后（服用100 mg阿替洛尔2小时后），在自行车上进行动态运动（50 - 200 W）之前及之后，测量外周血单个核细胞上β2-肾上腺素能受体的密度和亲和力，以及细胞内cAMP浓度（基线值和异丙肾上腺素刺激值）。动态运动对受体密度、亲和力以及基础cAMP值均无显著影响。急性β受体阻滞剂治疗后，动态应激引起的平均动脉血压升高显著（p < 0.01）降低，从33 mmHg降至24 mmHg，β-肾上腺素能受体密度显著（p < 0.05）增加，从1320个分子/细胞增至2102个分子/细胞，而亲和力保持不变。基线和刺激后的cAMP浓度分别显著（p < 0.05）升高，从5.3 pmol/10⁶细胞增至7.0 pmol/10⁶细胞，以及从2.1 pmol/10⁶细胞增至3.5 pmol/10⁶细胞。这些发现表明，在原发性高血压患者中，运动时β2-肾上腺素能受体-腺苷酸环化酶-cAMP系统的调节受损，急性β受体阻滞剂治疗可使其恢复正常。由于阿替洛尔主要阻断β1-肾上腺素能受体，观察到的淋巴细胞BAAS恢复正常可能仅反映了抗高血压治疗本身的非特异性作用。
