Eicosanoid production, metabolism and contractile activity in the isolated uterus from non-insulin-dependent diabetic rats during late pregnancy.
Eicosanoid production, glucose (Glu), glycogen (Gly) and triglyceride (TG) metabolism, spontaneous contractile activity, PGF2 alpha and oxytocin-induced contractions have been studied in uterine tissue obtained from control (C) and non-insulin-dependent diabetic (D) rats prior to parturition. Parturition occurs on day 22 of gestation in control animals, whereas a 24 hr delay was observed in diabetic rats. Production of PGE2, PGE1, 6-keto-PGF1 alpha, PGF2 alpha, TXB2 and LTB4 was similar in uterine tissue obtained from control and diabetic rats on day 21 of pregnancy. Uterine metabolism, on day 21 of pregnancy, based on the production of 14CO2 from U14C-glucose was lower in tissues obtained from diabetic rats than in controls. Levels of TG were similar at 0 hr and after 60 min incubation in Glu or Glu-free medium in both experimental groups. Initially Gly levels in diabetic and control uteri were similar. After 60 minutes of incubation, levels of Gly in control tissue decreased only in the absence of Glu in the incubation medium. In contrast, in diabetic uterine strips, levels of Gly decreased after 60 minutes of incubation either in Glu or Glu-free medium. "In vitro" isometric-developed tension (IDT) evaluated on day 21 (C and D) and 22 (D) of pregnancy was similar at 0 hr in control and diabetic uterine preparations, but IDT in both diabetic groups was decreased after a 40 minute incubation when compared to controls. Alterations in PGF2 alpha-induced uterine responses were not seen in 21 or 22 days pregnant diabetic uterine tissue when compared to controls. In contrast, impaired oxytocin responses were observed in diabetic uteri on day 21 of gestation, but they were similar to control responses of uterine tissue from day 22 diabetic rats. We conclude that in the non-insulin-dependent late pregnant rat, there are no alterations in uterine tissue eicosanoid production, but metabolic and contractile abnormalities are present. Involvement of these alterations in the delayed initiation of parturition is discussed.
Jawerbaum
A
A
Centro de Estudios Farmacológicos y Botánicos (CEFYBO), Consejo Nacional de Investigaciones Científicas y técnicas (CONICET), Buenos Aires, Argentina.
Catafau
J R
JR
Gonzalez
E T
ET
Novaro
V
V
Gómez
G
G
Gelpi
E
E
Gimeno
M A
MA
D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism*; D015237:Dinoprost / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D015777:Eicosanoids / Q000378:metabolism*; D005260:Female; D005947:Glucose / Q000378:metabolism; D006003:Glycogen / Q000032:analysis; D066298:In Vitro Techniques; D007537:Isometric Contraction; D010121:Oxytocin / Q000494:pharmacology; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D013311:Streptozocin; D013997:Time Factors; D014280:Triglycerides / Q000032:analysis; D014590:Uterine Contraction; D014599:Uterus / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism*
D015777:Eicosanoids; D014280:Triglycerides; D010121:Oxytocin; D013311:Streptozocin; D006003:Glycogen; D015237:Dinoprost; D005947:Glucose