Hurd W W, Smith A J, Gauvin J M, Hayashi R H
Department of Obstetrics and Gynecology, University of Michigan Medical Center, Ann Arbor.
Obstet Gynecol. 1991 Aug;78(2):249-53.
Premature labor is one of the most common complications associated with cocaine abuse during pregnancy. Still, the effect of cocaine on the pregnant uterus is largely unknown. Although inhibition of neuronal uptake is the most important effect of cocaine in most tissues, after mid-pregnancy, the uterus has few functioning adrenergic nerve endings. To determine whether cocaine has any effect on uptake during pregnancy, we evaluated the ability of the term pregnant human uterus to take up [3H]-norepinephrine (9 x 10(-8) mol/L) and the ability of cocaine (10(-6)-10(-8) mol/L) to block this uptake. Because d-propranolol has been shown to block the direct effects of cocaine on the pregnant rabbit uterus, we also evaluated the ability of d-propranolol (2 x 10(-6) mol/L) to block the effect of cocaine on catecholamine uptake. The ability of the Uptake 2 inhibitor hydrocortisone (2 x 10(-5) mol/L) to block catecholamine uptake was also studied. We found that [3H]-norepinephrine was taken up by both the pregnant myometrium and endometrium, and that cocaine blocked this uptake by up to 55% at concentrations as low as 10(-7) mol/L. D-propranolol had no effect on the ability of cocaine to block catecholamine uptake. Hydrocortisone blocked uptake by the endometrium by 15% but did not block uptake by the myometrium. We conclude that the pregnant human uterus at term retains the ability to take up catecholamines and that cocaine blocks this extraneuronal uptake. This may explain, in part, the association of cocaine use with premature labor.
早产是孕期与可卡因滥用相关的最常见并发症之一。然而，可卡因对妊娠子宫的影响在很大程度上尚不清楚。尽管抑制神经元摄取是可卡因在大多数组织中最重要的作用，但妊娠中期后，子宫中几乎没有起作用的肾上腺素能神经末梢。为了确定可卡因在孕期是否对摄取有任何影响，我们评估了足月妊娠人体子宫摄取[3H] - 去甲肾上腺素（9×10^(-8)摩尔/升）的能力以及可卡因（10^(-6) - 10^(-8)摩尔/升）阻断这种摄取的能力。由于已证明d - 普萘洛尔可阻断可卡因对妊娠兔子宫的直接作用，我们还评估了d - 普萘洛尔（2×10^(-6)摩尔/升）阻断可卡因对儿茶酚胺摄取影响的能力。还研究了摄取2抑制剂氢化可的松（2×10^(-5)摩尔/升）阻断儿茶酚胺摄取的能力。我们发现[3H] - 去甲肾上腺素被妊娠子宫肌层和子宫内膜摄取，并且可卡因在低至10^(-7)摩尔/升的浓度下可将这种摄取阻断高达55%。d - 普萘洛尔对可卡因阻断儿茶酚胺摄取的能力没有影响。氢化可的松使子宫内膜摄取减少15%，但未阻断子宫肌层的摄取。我们得出结论，足月妊娠人体子宫保留摄取儿茶酚胺的能力，并且可卡因阻断这种非神经元摄取。这可能部分解释了可卡因使用与早产之间的关联。
