Utero-relaxant effect of PDE4-selective inhibitor alone and in simultaneous administration with beta2-mimetic on oxytocin-induced contractions in pregnant myometrium.
BACKGROUND
The objective of the study was to observe the effect of rolipram, the prototype phosphodiesterase 4 selective inhibitor, on oxytocin-induced contractions of human term myometrial strips, and compare the effect with salbutamol, beta(2)-adrenergic agonist, in single and the simultaneous application.


METHODS
Human myometrium was obtained from pregnant women in term that had a term delivery by the caesarian section. Myometrial strips were excised from the lower uterine segment and placed into an organ-bath with Krebs-Henseleit buffer. The mean peak amplitude of contraction (mN) of the myometrial smooth muscle to the doses of oxytocin (10(-6) mmol/L(-1)) with subsequent single administration of rolipram (10(-4) mmol/L(-1)), salbutamol (10(-4) mmol/L(1)) and simultaneous administration of rolipram and salbutamol (both 10(-4) mmol/L(-1)), was used as a parameter of myometrial reactivity.


RESULTS
Rolipram alone decreased the oxytocin-induced contractile amplitude to 47.98%, single salbutamol application resulted in amplitudinal decrease to 56.07%, and the combination of both compounds in their simultaneous administration resulted in the decrease of oxytocin-induced contractile amplitude to 29.1%.


CONCLUSIONS
Our data are consistent with previous studies of the enhanced efficiency of the beta(2)-adrenergic agonist, when administered together with the phosphodiesterase 4-inhibitor. Moreover we have shown that rolipram alone has a more profound effect on oxytocin-induced contractions than salbutamol alone.
Franova
Sona
S
Department of Pharmacology, Jessenius Faculty of Medicine, Comenius University, Martin, Slovakia. franova@jfmed.uniba.sk
Janicek
Frantisek
F
Visnovsky
Jozef
J
Dokus
Karol
K
Zubor
Pavol
P
Sutovska
Martina
M
Nosalova
Gabriela
G
D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000420:Albuterol / Q000494:pharmacology*; D004357:Drug Synergism; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D009215:Myometrium / Q000187:drug effects / Q000201:enzymology; D010121:Oxytocin / Q000494:pharmacology; D058988:Phosphodiesterase 4 Inhibitors; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology*; D011247:Pregnancy; D020889:Rolipram / Q000494:pharmacology*; D014590:Uterine Contraction / Q000187:drug effects*
D000318:Adrenergic beta-Agonists; D058988:Phosphodiesterase 4 Inhibitors; D010726:Phosphodiesterase Inhibitors; D010121:Oxytocin; D020889:Rolipram; D000420:Albuterol