HORMONAL CONTROL OF MALPIGHIAN TUBE AND RECTAL FUNCTION IN DESERT LOCUST SCHISTOCERCA GREGARIA

The neurosecretory system regulates excretion in two distinct ways by acting upon the Malpighian tubules and the rectum. The rate of excretion of amaranth through the Malpighian tubules is related to neurosecretory activity. Extracts of corpora cardiaca increase both the excretion of amaranth and potassium urate through the Malpighian tubules. Isolated inverted rectal sacs have been used to follow reabsorption from the rectal lumen into the haemolymph, and it has been shown that factors from the corpora cardiaca reduce this reabsorption. The rate of turnover of the neurosecretory factors regulating excretion has been estimated. © 1969.