Osmoregulation in Blaberus craniifer after parenteral injections of NaCl solutions

Abstract

After injection of NaCl into the abdominal hemocoel of BIaberus craniifer, the osmotic concentration of antenna1 hemolymph peaked at 1.25 hr and returned to pre-injection concentration by 21 hr. The mean plasma clearance was 2.67 @/hr.2. Force-feeding of water 15min after injection of NaCl prevented the early rise in hemolymph osmotic concentration, but a later gradual increase in osmotic concentration occurred.3. The onset of spontaneous drinking occurred 0.8 hr after NaCl injection; this correlated with an elevation in hemolymph osmotic concentration.4. Cumulative spontaneous water intake over 4 days was proportional to the daily injected dose of NaCl.