Decrease in myometrial beta-adrenergic receptors with prenatal cocaine use.

Journal Article

To determine if cocaine use during pregnancy is associated with a reduction in the number or affinity of beta-adrenergic receptors in human myometrium.Myometrium was obtained at cesarean delivery of five women who reported using cocaine during pregnancy and from ten controls. Saturation binding assays were performed on the myometrial membrane fractions using [125I]-cyanopindolol to determine beta-adrenergic receptor concentration and affinity. The percentages of beta 1- and beta 2-adrenergic receptors were determined in three cocaine users and four control patients by performing competition binding assays using the beta 2 antagonist ICI 118,551. Results were compared using unpaired Student t tests.Women who reported using cocaine during pregnancy had a significantly lower mean (+/- standard deviation) concentration of myometrial beta-adrenergic receptors than did controls (22 +/- 8 versus 52 +/- 23 fmol/mg protein, respectively). There was no difference in the receptor affinity constants between cocaine users and controls (16 +/- 2 pmol/L for both groups). The percentages of beta 1- and beta 2-adrenergic receptors in the myometrium of the cocaine-use group and control group were similar: 86 +/- 1% beta 2 in the cocaine-use group and 83 +/- 7% beta 2 in the control group.Cocaine use during pregnancy may be associated with a down-regulation of beta-adrenergic receptors in human myometrium. This could result in a decreased capacity for uterine relaxation and, consequently, a predisposition to preterm labor.

Full Text

Duke Authors

Cited Authors

  • Smith, YR; Dombrowski, MP; Leach, KC; Hurd, WW

Published Date

  • March 1995

Published In

Volume / Issue

  • 85 / 3

Start / End Page

  • 357 - 360

PubMed ID

  • 7862372

Electronic International Standard Serial Number (EISSN)

  • 1873-233X

International Standard Serial Number (ISSN)

  • 0029-7844

Digital Object Identifier (DOI)

  • 10.1016/0029-7844(94)00424-c

Language

  • eng