[An extraluminal strain gage force transducer: its construction and implantation (author's transl)].

1. Extraluminal strain gage force transducers have been designed and constructed in this laboratory. This device was originally developed to measure contractile force of the heart by Walton et al in 1950, however, we concentrated our effort upon durability and waterproof of the transducer in the present study. 2. Strain gages which were made for measuring large strain were prepared and bonded onto the both surfaces of CuBe strips with epoxy lesin. Water proof was then made by applying silicone (KE 45 RTV), which was excellent in waterproof, insulation and flexibility. The silicone was also found no significant influence upon the surrounding tissues as a foreign body. 3. The transducer constructed in this way had useful life for 3-6 months after implantation. Chronically implanted transducer units offer several advantages: they provide prolanged observation of gastrointestinal mechanical activity directly in conscious animals. They can be sutured on the outer surface of the gastrointestinal tract and do not interfere flow of intraluminal contents. They can measure separate contractile force of the circular and longitudinal muscle layers. 4. Major limination of the transducer is difficulty to determine if a given sequence of movements are mixing or propulsion of the contents. Application of these transducers is currently limited in animal only.