Subfornical organ stimulation elicits drinking.

The subfornical organ is a specialized central nervous system structure known to be involved in the control of drinking. We report here that electrical activation of subfornical organ neurons (100 microA, 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 electrode placements (n = 7) dorsal or rostral to the subfornical organ drank in response to electrical stimulation. In contrast, activity levels were increased significantly during stimulation in both the subfornical and nonsubfornical organ stimulated groups. These results suggest that electrical stimulation of the subfornical organ can elicit site-specific drinking behaviour and provide further support for the involvement of the subfornical organ in the control of drinking behaviour.