Olivocochlear neurons in the chinchilla: a retrograde fluorescent labelling study.

Although the chinchilla is widely used as a model for auditory research, little is known about the distribution and morphology of its olivocochlear neurons. Here, we report on the olivocochlear neurons projecting to one cochlea, as determined by single and double retrograde fluorescent tracer techniques. 10 adult chinchillas were anesthetized and given either unilateral or bilateral injections of a fluorescent tracer (either Fluoro-Gold or Fast Blue) into scala tympani or as a control, a unilateral injection into the middle ear cavity.

The effect of the route of nutrient delivery on gut structure and diamine oxidase levels.

Diamine oxidase (DAO) is an intestinal mucosal enzyme which serves as a marker of cellular maturity and integrity in ontogeny and after mucosal injury in the gastrointestinal tract. Since total parenteral nutrition is known to result in intestinal hypoplasia, this study was done to determine the effect of enteral and parenteral delivery of nutrients on gut structure and DAO levels. Central venous catheters were placed in 27 Sprague-Dawley rats (180-260 g), which received nutrients for 12 days via parenteral nutrition (GpI n = 10), oral intake of the parenteral solution (GpII n = 8), or standard rat chow (GpIII n = 9).