Abstract
In order to make clear the controlling sites of feed intake in the chicken, the cell morphology and the enzymatic activities in the posterior hypothalamus and their changes after fasting were surveyed. (1) Cell types and enzymatic activities in many nuclei of the posterior hypothalamus coincided with those of mammals. (2) Activities of acetylcholinesterase and acid phosphatase were high in the nervous cell body and they varied in the same manner after fasting. Activities of monoamine oxidase and alkaline phosphatase were high outside the cell body, and after fasting alkaline phosphatase activity was increased, though monoamine oxidase activity was unchanged. (3) Large ovoidal cells in LHT were enlarged after fasting for three days. Their activities of acetylcholinesterase and acid phosphatase were high, though they became lower after fasting for three days. (4) Middle-sized ovoidal cells in IH did not change after fasting for three days. Their activities of acetylcholinesterase and acid phosphatase were low, though they became higher after fasting for three days. (5) After fasting for seven days, cells of many nuclei inclined to become smaller, and their activities of acetylcholinesterase, acid phosphatase and alkaline phosphatase became higher. These changes were observed markadly in LHT and IH. (6) These results showed that large cells in LHT and middle-sized cells in IH might play roles in controlling feed intake, and it was speculated that acetylcholinesterase in these sites would be concerning to controlling feed intake.
