Cocaine directly augments the alpha-adrenergic contractile response of the pregnant rabbit uterus.
Journal Article (Journal Article)
Cocaine use in pregnancy is associated with a premature labor rate as high as 50%, but little is known about its effect on uterine contractility. To determine whether cocaine directly augments pregnant uterus contractility, uterine strips from 27-day pregnant New Zealand White rabbits (term, 31 days) were exposed to cocaine alone (30 mumol/L) or cocaine plus epinephrine (10(-9) to 10(-5) mol/L) or oxytocin (10(-10) to 10(-6) mol/L). Cocaine alone produced no contractions, but increased the epinephrine sensitivity by 51% and the maximal response by 33%. When beta-adrenoceptors were blocked with DL-propranolol (2 mumol/L), the contractile response to epinephrine was increased, and cocaine's effect was blocked. In the presence of the stereoisomer D-propranolol (2 mumol/L) with no beta-adrenergic antagonist activity, the contractile response to epinephrine was unchanged, but the effect of cocaine was still blocked. We conclude that cocaine directly augments the alpha-adrenergic contractile response of the pregnant rabbit uterus by a mechanism that is blocked by the non-beta-adrenergic effects of propranolol.
Full Text
Duke Authors
Cited Authors
- Hurd, WW; Robertson, PA; Riemer, RK; Goldfien, A; Roberts, JM
Published Date
- January 1, 1991
Published In
Volume / Issue
- 164 / 1 Pt 1
Start / End Page
- 182 - 187
PubMed ID
- 1670909
International Standard Serial Number (ISSN)
- 0002-9378
Digital Object Identifier (DOI)
- 10.1016/0002-9378(91)90651-7
Language
- eng
Conference Location
- United States