Date of Award

1994

Degree Type

Dissertation

Degree Name

Doctor of Philosophy

Abstract

The present study examined the possible importance of uterine vascular permeability (VP), extracellular fluid volume (ECFV) and blood flow (BF) in the enhanced accumulation of serum proteins in uterine tissue destined to undergo decidualization. This process is identifiable by endometrial blueing after intravenous (i.v.) injection of Evans blue dye. It was hypothesized that VP, ECFV and BF must increase to promote the enhanced intrauterine accumulation of serum proteins and that these uterine vascular and perivascular changes require optimal endometrial sensitization and prostaglandins (PGs).;ECFV was estimated by the uterine volume of distribution of i.v. injected {dollar}\sp{lcub}51{rcub}{dollar}Cr-EDTA, VP by the rate of increase of the uterine volume of distribution of albumin after i.v. injection of {dollar}\sp{lcub}125{rcub}{dollar}I-albumin, and BF by the microsphere technique. In one experimental manipulation, unilateral, artificial deciduogenic stimulation was given to the uteri of rats after either optimal or suboptimal sensitization for decidualization. In another manipulation, decidualization was first inhibited by intrauterine infusion of indomethacin (IM) then reinstated by simultaneous infusion of prostaglandin E{dollar}\sb2{dollar} (PGE{dollar}\sb2{dollar}) with the IM.;When stimulation was given to an optimally sensitized uterus, both VP and ECFV were significantly higher in stimulated than nonstimulated horns during the time when the endometrial blueing reaction can be demonstrated by i.v. injection of Evans blue dye. VP became significantly increased by 4 hours after stimulation while significant increases in ECFV followed at 8 hours. Deviation from optimal sensitization and infusion with IM eliminated or significantly reduced the elevated ECFV and VP in simulated horns. This effect of IM was reversed by coinfusion with PGE{dollar}\sb2{dollar}. In most cases, increases in total BF were proportional to increases in uterine weight producing consistent uterine tissue BF (3-4 {dollar}\mu{dollar}l/min/mg). Excessive estrogen sensitization and coinfusion of PGE{dollar}\sb2{dollar} and IM for 20 hours resulted in uterine weight gains which were not accompanied by proportional increases in total uterine BF. For these treatments, uterine tissue BF was significantly reduced.;The results of this study indicate that transient increases in uterine VP and ECFV occur during the time when the uterine blueing reaction can be demonstrated. The fact that uterine VP and ECFV nearly always changed in parallel suggests that these variables are either directly related or share a common control element. However, the possibility that the 2 variables play independent roles in the uterine blueing reaction cannot be excluded. Increased uterine BF does not appear to be an essential component of the blueing phenomenon. The use of contrast-enhanced magnetic resonance imaging techniques provided identification of predecidual tissue in dissected uteri and in the uteri of intact, anaesthetized rats. The elevated ECFV in predecidual tissue appears to be largely responsible for the image enhancement.

Share

COinS
 
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.