Reflex bleeding

Ladybird beetles produce a wide variety of polyacetate or fatty acid-derived alkaloids, many of which closely resemble the ant venom alkaloids described in the previous section. The original discovery of coccinelline (75) and precoccinelline (100) (Figure 32) in blood of the European ladybird beetle, C. 1-punctata had been motivated in part by these beetles aposematic coloration and their tendency to reflex-bleed when molested. Many ladybird beetle species share these characteristics and correspondingly are chemically protected by alkaloids as well. The carbon skeletons of almost all of these alkaloids are based on simple unbranched chains. The structures, biology, and laboratory syntheses of ladybird beetle alkaloids have been reviewed previously by Daloze et al and by Glisan King and Meinwald. ... 

CigHsgNj, Mr 282.51, yellowish oil, [a] -i-3.95° (ben-zeneX A defence substance of ladybird beetles (Coc-cinellidae) of the genus Harmonia occurring in the he-molymph of mature insects. On attack by a predator, H. is liberated by so-called reflex bleeding from the knee axilla. 

Synthesized in the meloid beetle Lytta vesicatoria present in the blood, released by reflex bleeding from joints, feeding deterrent... 

A wide variety of defense substances occur in insects. They are either accumulated simply in the insect s body, like the cardiac glycoside calotropin in the monarch butterfly, or they are constituents of the hemolymph and are discharged, e.g., by reflex bleeding, when a predator attacks the insect, as with cantharidin from the meloid beetle. In some cases the products may be actively expelled. A characteristic example in this respect is the ejection of quinones from special glands of the bombardier beetles Brachynus sp.) (Fig. 338). 

Plate 3 The seven-spotted ladybird Coccinella septempunctata, which produces precoccinelline and coccinelline by reflex bleeding. 

In most cases of secondary protection of insect herbivores by alkaloids the source of the alkaloid is the herbivore diet, i.e. the plant host. There have been several interesting reports on the occurrence of chemical defenses of insects based on alkaloids actively synthesized or at least chemically modified by the insect. One such report showed that deterrence to predation by ants and spiders was afibrded to the Mexican bean beetle Epilachna varivestis) by the production of the homotropane alkaloid euphococcinine (66). This compound which actually may be a polyketide, is not present in the body of larvae or newly hatched adults but is accumulated in the beetles blood within one week of emergence. When attacked, the beetle reflex-bleeds emitting droplets of blood containing as much as 5 pg of euphococcinine. 

Neuro Within normal limits (gross sensory, motor, reflexes) GU Valsalva caused urine spurt friable, bleeding vaginal lining on pelvic exam... 

Lethal, 3 to 10 days respiratory depression, hypertensive crisis, cerebral bleeding, loss of deep tendon reflexes, decreased renal function, decreased liver function... 

Administered to mice, 49,000 ppm for 51 minutes resulted in narcosis, muscular hypotonia, disappearance of corneal reflexes, then coma followed by death. The LC50 was estimated to be 21,000 ppm in rats exposed for 3 hours. Repeated exposure of rats to concentrations ranging from 100 to 5000 ppm for 12 weeks caused a dose-related increase in irritation of the mucous membranes. At the 5000 ppm level there was marked edema or opacity of the cornea, salivation, and discharge or bleeding in the nasal mucosa. 

Adverse effects in patients include nausea, vomiting, anorexia, diarrhea, abdominal pain, pharyngitis, stomatitis, enterocolitis, rectal bleeding, blood anomalies, paresthesias, peripheral neuritis, mental depression, loss of tendon reflexes, headache, and convulsions.2... 

There was little bleeding. And multiple needle prickings into the thumb abductor were not felt. A quick plunge of the tip of my little finger into boiling water elicited reflex response, but no residual pain. Judgment was OK, so I stayed out of physical trouble, luckily ... 

Low muscle pH with normal blood pH, the most common cd>normality seen, occurs in patients with clinical problems which cause a decrease in tissue perfusion such as bleeding, extracellular fluid deficit, decreases in cardiac output, and any condition which causes peripheral vasoconstriction and/or vasculitis. In children with decreased tissue perfusion, muscle pH as low as 6.60 has been observed. The lowest values have occurred during massive hemorrhage. Often muscle pH decline in hemorrhage, a result of reflex peripheral vasoconstriction, occurs before a fall in central blood pressure. 

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