Catecholamine-containing nerve fibres in the human abdominal vagus.

The vagal nerve of man has been investigated for the presence of adrenergic nerve fibres using the histochemical fluorescence method of Hillarp and Falck. Following 30-60 min of nerve ligation during surgical operations, the right anterior main trunk (subdiafragmatic level) from one patient, and the anterior nerve of Latarget of 5 patients were found to contain unmyelinated nerve fibres with accumulations of green fluorescent material representing a catecholamine. The observations indicate the presence of adrenergic nerve fibres running caudally in the human vagal nerve, in accordance with similar findings in other mammals, e.g. cats and dogs.