Factors affecting gastric secretion in thoracic-duct lymph of dogs

¹ Section of Physiology, Mayo Clinic and Mayo Foundation, Rochester, Minnesota

Thoracic-duct lymph was collected from dogs during various phases of gastric secretion. The lymph samples were injected intravenously into dogs with vagally innervated and denervated pouches while these were secreting at slow rates in response to the continuous intravenous injection of small quantities of histamine. About half the samples inhibited gastric secretion. The rest produced transient stimulation or had no effect. The greatest degree of inhibition occurred when lymph collected immediately after a meal was injected. When fatty lymph was separated into fat and nonfat fractions, the fat-containing portion of lymph stimulated gastric secretion slightly, while the nonfat fraction carried the inhibitory influence when it was present. Systemic reactions were noted in one-third of the animals that had an inhibitory response. The occurrence of stimulatory or inhibitory factors in the lymph did not appear to be related to particular phases of gastric secretion.