Induction of transport of organic anions in Malpighian tubules of Rhodnius.
1. The ability of Rhodnius Malpighian tubules to transport organic anions such as p-aminohippuric acid (PAH) and amaranth depends on the physiological state of the insect. Unfed insects progressively lose this ability, but the transport mechanisms rapidly become activated after a blood meal. 2. This induction occurs in adults as well as larval instars and is not prevented by decapitation. 3. No increase in rates of excretion of organic anions follows a meal of Ringer's solution or a single injection of 0-1 mumoles of PAH into the haemolymph. 4. Accelerated PAH excretion is induced in insects fed (a) blood plasma alone or a suspension of red blood cells in saline, (b) solutions of serum albumin or casein, and (c) whole or diluted milk. 5. These results show that the ingestion of a protein-rich meal is sufficient to induce an accelerated transport of organic anions such as PAH and they suggest that this induction is not controlled by a hormone released in response to abdominal distension but depends instead on the continued presence in the haemolymph of some product of digestion of the meal.
D000367:Age Factors; D000548:Amaranth Dye / Q000378:metabolism*; D000618:Aminohippuric Acids / Q000378:metabolism*; D000818:Animals; D001391:Azo Compounds / Q000378:metabolism*; D001692:Biological Transport; D002988:Cloaca / Q000378:metabolism*; D003655:Decerebrate State; D005508:Food Deprivation; D007814:Larva; D008317:Malpighian Tubules / Q000378:metabolism*; D012239:Rhodnius / Q000378:metabolism*; D014225:Triatominae / Q000378:metabolism*
D000618:Aminohippuric Acids; D001391:Azo Compounds; D000548:Amaranth Dye