Amniotic Fluid Prolactin: RESULTS(3)

RESULTS(3)

In all animals except one, increases in amniotic fluid concentrations of IL-1 (3 and TNFa preceded the decreases in amniotic fluid prolactin (Table 1). An increase in PGE2 also preceded the decrease in prolactin (Table 2). Progesterone levels in the amniotic fluid, maternal artery, and fetal vein were higher at the onset of labor (after infection) than prior to infection, indicating that the decrease in prolactin was not due to a decrease in progesterone in any of these compartments (Table 3). The progesterone, IL-1 p, TNFa, and PGE2 concentrations resulting from the intraamniotic inoculations were reported earlier in a different format and are presented here to facilitate comparison.

IL-Ц3 Infusion

A brief infusion of IL-ip also caused a decrease in amniotic fluid prolactin that was followed by labor in 5 of 6 animals. In the case in which labor did not occur, amniotic fluid prolactin then returned to normal after 4 days (n = 1). Figure 4A shows results for a representative animal that was infused with 10 |xg of IL-1 (3. Delivery at night ensued 2.5 h after the last sample. The prolactin levels of the 6 animals were stratified into three time periods for statistical analysis, and the results are shown in Figure 5, A and B. There was a significant decline in prolactin immediately after infusion that was maintained to 72 h. These results are similar to the results obtained with intraamniotic bacterial infection. buy asthma inhalers

In the animals from which the prolactin levels were obtained, there was a 2-fold increase in PGE2 from 3.5 ± 2.6 to 7.2 ± 2.8 ng/ml (p < 0.05). In addition, there was an increase in uterine activity at 6.0 ± 2.45 h from infusion. Five of the six animals delivered at 73.8 ± 28.8 h after infusion, and one animal delivered 8 days after infusion.

IL-1 fi Plus Indomethacin

Administration of indomethacin together with IL-ip prevented the increase in PGE2 that was observed with infusion of IL-ip alone. PGE2 levels were 0.20 ± 0.08 ng/ml prior to infusion of indomethacin and 0.35 ± 0.02 ng/ml (not different) during coadministration of indomethacin and IL-1 p. Hence, indomethacin prevented the increase in uterine activity and preterm labor that was associated with infusion of IL-1(3 alone. Figure 4B depicts a representative animal given 10 |xg of IL-lp and indomethacin.

TABLE 1. Amniotic fluid (AF) prolactin and experimental intraamniotic infection.

Animal # Inoculum Innoc. day of gestation Time following infection until:
Increases in uterine contractility Delivery Increases in AFTNFct Increases in AF IL-1 p Decline in AF prolactin
intraamniotic infection:
12283 10‘ GBS 132 32 h 50 h 22 h 22 h 12 h
11925 106 GBS 132 14 h 72 h 12 h 12 h 12 h
9836 106 GBS 126 40 h 53 h 6 h 22 h 39 h
11069 106 GBS* 132 none none none none none
Choriodecidual infection:
11067 103 GBS 137 50 h 62 h 8 h 24 h
14685 10» GBS 148 27 h 41 h 18 h 24 h

* Heat-inactivated 106 GBS.

TABLE 2. Mean amniotic fluid prolactin, IL-10, and PGE2 concentrations following experimental intraamniotic or choriodecidual infection in rhesus monkeys.

Prolactin ((j-g/ml) 034.0 1-12 h 33.9 13-24 h 22.5 Time following 25-36 h 22.0 infection 37-48 h 20.3 49-60 h 13.1* 61-72 h 9.7*
SEM 6.4 5.5 4.0 4.4 4.5 3.5 2.4
TNFa (pg/ml) 32 669 13,674 >20,000 >20,000 >20,000 >20,000
SEM 11 388 4903
IL-1 |J (pg/ml) 25 190 1072* 1734* 2142* 2037* 1848*
SEM 25 195 465 441 334 294 376
PGE2 (pg/ml) 2110 2753 8570* 11,366* 12,484* 10,380* 9349*
SEM 1695 1622 4684 4232 2853 2605 4844
Number of animals 6 6 6 6 6 4 3

* Significantly different from Time 0 at p < 0.05 (ANOVA and Duncan’s pairwise comparison).

TABLE 3. Amniotic fluid prolactin and progesterone concentrations before infection (basal) and following the onset of labor in rhesus monkeys (data presented as median and range in parentheses).

Basal Labor
Prolactin Amniotic 41.9 (13.0-47.1) 8.8 (2.2-30.4)*
(Hg/ml) fluid
Progesterone Amniotic 0.04 (0.03-0.07) 0.20 (0.05-2.05)*
(ng/ml) fluid
Maternal 2.6 (1.5-3.9) 5.5 (2.3-13.1)*
artery
Fetal vein 2.6 (1.6-5.8) 8.8 (2.4-14.9)*

* p < 0.05, Mann-Whitney U test.

This entry was posted in Intrauterine Infection and tagged Intrauterine Infection, lnterleukin, Pregnant Rhesus Macaques, Prolactin.