SUBFORNICAL ORGAN STIMULATION ELICITS DRINKING

The subfornical organ is a specialized central nervous system structur e known to be involved in the control of drinking. We report here that electrical activation of subfornical organ neurons (100 mu A, 10 Hz, 1 ms pulse width, for 5 min.) induced drinking in 67% (six of nine) of animals. This effect was site-specific as none of the animals with el ectrode placements (n = 7) dorsal or rostral to the subfornical organ drank in response to electrical stimulation. In contrast, activity lev els were increased significantly during stimulation in both the subfor nical and nonsubfornical organ stimulated groups. These results sugges t that electrical stimulation of the subfornical organ can elicit site -specific drinking behaviour and provide further support for the invol vement of the subfornical organ in the control of drinking behaviour.