Spontaneous action potentials recorded from the isolated, whole, encapsulated bovine pituitary gland: changes induced...

Extracellular spontaneous action potentials (SAP) were recorded from each lobe of the whole, isolated, encapsulated bovine pituitary gland bathed in Ringer's solution and maintained at 37 degrees C. All recordings were made with the gland in a shielded cage. Subdermal electrodes inserted into the various lobes of the gland were attached to a polygraph outside of the cage. Agents: dopamine (DA), norepinephrine (NE), gamma-aminobutyric acid (GABA) and serotonin (5HT) known to induce changes in the frequency and amplitude of the SAP in dissociated pituitary cells were used in this study. Although there are some questions about recording from dissociated pituitary cells in culture, in general, using these agents, there were no major differences in the SAP recorded from either dissociated cells in culture or cells in the whole intact bovine pituitary gland. Since pituitary cells and cells in nervous tissue share a common parentage, a comparative study of the SAP recorded from these cells show that the potentials recorded from cells in nervous tissue, e.g. ganglia, are inconsistent whereas those from pituitary cells show a consistent pattern of activity.