The frog has been used globally for more than a century to study nerve and nerve/muscle function and structure. We use the frog in teaching classic, experimental physiology to undergraduate students at Rutgers University. We also use the frog in our experimental laboratory. This paper describes an alternative approach for isolating and extracting sciatic nerves from the frog. Conventionally, a ventral approach has been used (with the euthanized/anesthetized frog lying on its back). In this paper we describe isolating the nerve using a dorsal approach (with the frog lying on its abdomen/coelom). Lifting the urostyle and carefully making bilateral incisions along the lateral margins of the backbones allows one to see both sciatic nerves while the surgery is being performed. These procedures also enable the investigator to trace the sciatic nerves to their origins in the vertebral column. Using this approach in bullfrogs has allowed us to isolate segments of nerve that exceed 80-90 mm in length (spinal column to knee). Of course in Rana pipens and similarly-small species, the lengths of isolated nerve are considerably shorter. In summary, our surgical and experimental methods and results have seemed to improve using a dorsal approach to isolating the frog sciatic nerves.
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