Fetal and Pediatric Pathology, Early Online:1–9, 2012 Copyright C  Informa Healthcare USA, Inc. ISSN: 1551-3815 print / 1551-3823 online DOI: 10.3109/15513815.2012.671648 Transcutaneous Electrical Nerve Stimulation and Placental Vascularization in Cases of Uterine Blood Flow Restriction Camila Souze de Oliveira Guimar ˜ aes, 1 Fab´ ıola Cristina Santos Tavares, 1 Mar´ ılia Neves Santos, 1 Greg ´ orio Corr ˆ ea Guimar ˜ aes, 2 Jana´ ınna Grazielle Pacheco Oleg´ ario, 1 Laura Penna Rocha, 1 Luiz Carlos Reis, 3 Marlene Ant ˆ onia dos Reis, 1 Eumenia Costa da Cunha Castro, 4 and Rosana Rosa Miranda Corr ˆ ea 1 1 Discipline of General Pathology, Biological Sciences Department, Triˆ angulo Mineiro Federal University, Uberaba, Brazil; 2 Department of Veterinary Medicine, Lavras Federal University, Lavras, Brazil; 3 Discipline of Physiology, Biological Sciences Department, Triˆ angulo Mineiro Federal University, Uberaba, Brazil; 4 University of Pittsburgh, Department of Pathology, Pittsburgh, Pennsylvania, USA Studies report transcutaneous electrical nerve stimulation (TENS) as a treatment for placental in- sufficiency. To induce utero-placental insufficiency in rats, the uterine artery was ligated. Tran- scutaneous electrical nerve stimulation was applied with a frequency of 80 Hz, pulse duration of 200 µs, and low intensity. Placental blood vessels were analyzed after immunohistochemistry. The number, caliber and area occupied by placental vessels, fetal weight and length, and placental vol- ume were lower in cases stimulated by TENS. The interaction between ligation and stimulation by TENS was associated with reduction of all these measurements, suggesting that TENS use during pregnancy may have harmful effects on intra-uterine development. Keywords pregnancy, transcutaneous electrical nerve stimulation (TENS), placental insuffi- ciency, blood vessels, intrauterine growth restriction INTRODUCTION e use of therapeutic electric currents is one of many means used in physiotherapy. Once adjusted to appropriate parameters, these currents can act in different ways, pro- moting analgesia and muscle contractions, improving muscle circulatory flow, as well as encouraging the rebuilding and healing of various tissues [1]. One of the major ther- apeutic electrical currents used in acute and chronic pain cases, transcutaneous elec- trical nerve stimulation (TENS), is used to influence and modulate the process of pain neuro-conduction and to act on the release of endogenous opioids [2]. In clinical prac- tice, it is predominantly used for symptomatic relief of pain, although there is an in- creased use of TENS as an anti-emetic and for restoration of blood flow in wounds and ischemic tissues. However, the circulatory effects of TENS are not yet well understood. A few reported experimental studies have presented contradictory results [3–5]. Address correspondence to Dr. Rosana Rosa Miranda Correa, Federal University of the Triˆ angulo Mineiro (UFTM), Uberaba, Brazil. E-mail: rosana@patge.uftm.edu.br  Fetal Pediatr Pathol Downloaded from informahealthcare.com by 189.41.82.244 on 04/19/12 For personal use only.