Mecca T E, Lamb F S, Hall J L, Webb R C
Proc Soc Exp Biol Med. 1985 Jun;179(2):248-53. doi: 10.3181/00379727-179-42094.
The effect of cerebral intraventricular administration of 6-hydroxydopamine (6-OHDA) on blood pressure and vascular smooth muscle responsiveness in deoxycorticosterone acetate (DOCA)-treated rats was assessed. Rats treated with 6-OHDA and DOCA had significantly lower systolic blood pressures (142 +/- 8 mm Hg) than rats treated with DOCA alone (185 +/- 5 mm Hg). After 5 weeks of DOCA treatment, femoral arteries and aortae were excised from these rats, cut helically into strips, and placed in a muscle bath to record isometric force. Dose-response curves to serotonin were shifted to the left in femoral arteries from DOCA-treated rats compared to both control and 6-OHDA-DOCA-treated rats (ED50: DOCA = 6.8 X 10(-8) M, control = 27.9 X 10(-8) M, 6-OHDA-DOCA = 13.4 X 10(-8) M). Arachidonic acid, the prostaglandin precursor, produced greater maximal contractions in femoral artery strips of DOCA-treated rats (358 +/- 56 mg) than in those from controls (115 +/- 31 mg). The maximal response to arachidonic acid in arteries from 6-OHDA-DOCA rats (203 +/- 78 mg) was not different from control values. Ouabain produced a greater maximal response in aortic strips from DOCA rats (658 +/- 165 mg) compared to those from control (196 +/- 72 mg) or 6-OHDA-DOCA (309 +/- 87 mg) rats. We conclude that increased vascular responsiveness to serotonin, arachidonic acid, and ouabain in DOCA hypertensive rats is secondary to a central action of the mineralocorticoid.
评估了脑室内注射6-羟基多巴胺(6-OHDA)对醋酸脱氧皮质酮(DOCA)处理的大鼠血压和血管平滑肌反应性的影响。用6-OHDA和DOCA处理的大鼠收缩压(142±8 mmHg)显著低于仅用DOCA处理的大鼠(185±5 mmHg)。DOCA处理5周后,从这些大鼠身上切除股动脉和主动脉,螺旋形切成条带,放入肌肉浴中记录等长力。与对照组和6-OHDA-DOCA处理的大鼠相比,DOCA处理的大鼠股动脉中对5-羟色胺的剂量-反应曲线向左移动(半数有效剂量:DOCA = 6.8×10⁻⁸ M,对照组 = 27.9×10⁻⁸ M,6-OHDA-DOCA = 13.4×10⁻⁸ M)。前列腺素前体花生四烯酸在DOCA处理的大鼠股动脉条带中产生的最大收缩力(358±56 mg)大于对照组(115±31 mg)。6-OHDA-DOCA大鼠动脉中对花生四烯酸的最大反应(203±78 mg)与对照值无差异。哇巴因在DOCA大鼠主动脉条带中产生的最大反应(658±165 mg)大于对照组(196±72 mg)或6-OHDA-DOCA大鼠(309±87 mg)。我们得出结论,DOCA高血压大鼠对5-羟色胺、花生四烯酸和哇巴因的血管反应性增加是盐皮质激素中枢作用的继发结果。