Rhythmic pulses of haemolymph pressure associated with parturition and ovulation in the tsetse fly,Glossina morsitans

Abstract Expulsion of the tsetse larva from the uterus of the female is preceded by 1–2 h of rhythmic pulses of haemolymph pressure that can be detected using a barographic technique. At first baseline pressure is maintained and all pulses are positive in relation to baseline. Then, about 1 h before parturition, baseline pressure increases, pulse intensity increases, and the pulses become both positive and negative in relation to baseline. Each pulse correlates with ‘bobbing’ action of the female's proboscis, the only external indication of this internal activity. A single large pressure pulse is observed at parturition, and thereafter the pressure level returns to the original baseline and pulsing action ceases. Around the presumptive time of ovulation, 1–2 h after parturition, another series of pressure pulses is observed. The pulses are the likely consequence of coordinated waves of muscular contraction that are essential preparation for successful parturition and ovulation.     

Diuresis and its hormonal control in butterflies

The sudden weight loss after eclosion in the butterflies Acraea horta, Danaus chrysippus and Papilio demodocus is largely due to diuresis. The potassium concentration of the haemolymph is approximately halved as a result, and extensive diuresis leads to increases in sodium concentration and total osmolarity. The isolated Malpighian tubules of all three species are stimulated to fast rates of fluid secretion by cyclic AMP and by homogenates of the brains and corpora cardiaca. The tubules of Papilio lose their sensitivity to stimulation after the first day of adult life, and ingestion of a large volume of artificial nectar by this butterfly does not cause diuresis.     

Effects of physico-chemical treatments on hemagglutination activity of Anopheles gambiae haemolymph and midgut extract

Abstract. Anopheles gambiae midgut extracts and haemolymph possessed agglutinins, titre 1:16 to 1:256, against human red blood cells (RBCs). Subjection of both tissues to protein precipitation reagents, organic chemical and selected protease, neuraminidase and other glycosidic hydrolase treatments revealed the haemagglutinins to be protein, most likely glycoprotein, in nature - not lipoprotein, lipid, glycolipid or nucleic acid. An.gambiae agglutinins were thermo-labile >40^oC, affected by freezing and thawing treatments, and contained disulphide and hydrogen bonds on the basis of sensitivity following exposure to dithio-threitol and urea respectively. Optimum haemagglutination depended generally on slightly acid to neutral pH conditions and agglutinin activity was Ca²⁺ ion, albeit to a lesser extent Mg²⁺ ion, dependent. The midgut extract agglutinin subunit molecule had a relative molecular weight (M_r) of 65kDa whilst that of haemolymph was 40kDa.
This study presents the first report on selected physico-chemical properties, the glycoproteinaceous nature and tentative subunit M_r of mosquito midgut extract and haemolymph anti-RBC agglutinin(s).     

Uric acid levels during last larval instar of Manduca sexta, an abrupt transition from excretion to storage in fat body

Levels of uric acid in the whole body of the tobacco hornworm, Manduca sexta increased steadily for the 9 days of the fifth instar. However, concentrations in the haemolymph were lowest during the transition from the feeding stage to the wandering stage (days 3, 4), the time when there was a switch from uric acid excretion by the Malpighian tubule-hindgut system to storage in the fat body. Haemolymph volumes, determined for larvae between 2 and 6 days into the fifth instar by isotope dilution with [¹⁴C]-inulin, were used to calculate rates of incorporation of uric acid into Malpighian tubules and fat body of larvae injected with [¹⁴C]-uric acid. These labelling studies indicated that the Malpighian tubules ceased to remove uric acid from the haemolymph some time between the last 6 hr of day 3 of the fifth instar and the first 18 hr of day 4. At the same period, fat body removed significant quantities of uric acid from the haemolymph. The times of initial decreases and increases in levels of uric acid in haemolymph and fat body, respectively, indicated that storage in the fat body started before cessation of elimination via the Malpighian tubule-hindgut system.     

Determination of ions, amino acids/amines in the haemolymph of fairy shrimps by capillary electrophoresis with indirect UV and laser-induced fluorescence detection

We identified and quantified the major inorganic ions present in a haemolymph of four species of fairy shrimp, to determine its ionic strength, using capillary electrophoresis, non-destructive micro-technique for the analysis of small amounts of body fluids. This is the first speciation and quantitative analysis of inorganic ions in the haemolymph of fairy shrimps.