Reproduction, Fertility and Development Reproduction, Fertility and Development Society
Vertebrate reproductive science and technology
RESEARCH ARTICLE

The effects of sildenafil citrate on feto–placental development and haemodynamics in a rabbit model of intrauterine growth restriction

Jorge López-Tello A , María Arias-Álvarez A , Maria-Ángeles Jiménez-Martínez B , Alicia Barbero-Fernández B , Rosa María García-García C , María Rodríguez D , Pedro L. Lorenzo C , Laura Torres-Rovira A , Susana Astiz E , Antonio González-Bulnes E F and Pilar G. Rebollar D G
+ Author Affiliations
- Author Affiliations

A Department of Animal Production, Veterinary Faculty, Complutense University of Madrid, Ciudad Universitaria, s/n, 28040, Madrid, Spain.

B Department of Animal Medicine and Surgery, Veterinary Faculty, Complutense University of Madrid, Ciudad Universitaria, s/n, 28040, Madrid, Spain.

C Department of Physiology (Animal Physiology), Veterinary Faculty, Complutense University of Madrid, Ciudad Universitaria, s/n, 28040, Madrid, Spain.

D Department of Animal Production, Polytechnic University of Madrid, Ciudad Universitaria, s/n, 28040, Madrid, Spain.

E Comparative Physiology Lab, SGIT-INIA, Avda, Puerta de Hierro, s/n, 28040, Madrid, Spain.

F Department of Veterinary Medicine, University of Sassari, Via Vienna 2, 07100, Sassari, Italy.

G Corresponding author. Email: pilar.grebollar@upm.es

Reproduction, Fertility and Development 29(6) 1239-1248 https://doi.org/10.1071/RD15330
Submitted: 13 August 2015  Accepted: 28 March 2016   Published: 23 May 2016

Abstract

The present study evaluated the effectiveness of sildenafil citrate (SC) to improve placental and fetal growth in a diet-induced rabbit model of intrauterine growth restriction (IUGR). Pregnant rabbits were fed either ad libitum (Group C) or restricted to 50% of dietary requirements (Group R) or restricted and treated with SC (Group SC). The treatment with SC improved placental development by increasing vascularity and vessel hypertrophy in the decidua. The assessment of feto–placental haemodynamics showed higher resistance and pulsatility indices at the middle cerebral artery (MCA) in fetuses treated with SC when compared with Group R, which had increased systolic peak and time-averaged mean velocities at the MCA. Furthermore, fetuses in the SC group had significantly higher biparietal and thoracic diameters and longer crown–rump lengths than fetuses in Group R. Hence, the SC group had a reduced IUGR rate and a higher kit size at birth compared with Group R. In conclusion, SC may provide potential benefits in pregnancies with placental insufficiency and IUGR, partially counteracting the negative effects of food restriction on placental development and fetal growth. However, the present study also found evidence of a possible blood overflow in the brain that warrants further investigation.

Additional keywords: fetus, placenta, pregnancy.


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