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4.4.2.3 Summary of the Properties and Toxinology of M. monspessulanus
Duvernoy's Secretion
There are few data regarding yield of Duvernoy's secretion from M. monspessulanus ,
and no yield data for M. moilensis . Using fluothane for anesthesia and pilocarpine for
parasympathomimetic stimulation of secretion, Rosenberg et al. (1985) reported a
yield of 0.63 μL/g of snake body weight. Although solid yield was not reported, the
liquid secretion contained 9.0 mg protein/mL. A later study compared extraction using
fluothane with ketamine hydrochloride or fluothane alone (both methods included
pilocarpine) and obtained contrasting volumes (Rosenberg et al., 1992). The former
method yielded 0.44 μL/g snake body weight, while the latter obtained 5.2 μL/g snake
body weight. Protein content was not reported (Rosenberg et al., 1992).
The two studies assaying enzymatic activities in secretion from M. monspessulanus
described phosphodiesterase, alkaline phosphatase, acid phosphatase, caseinase, and/or
PLA activities (Ovadia, 1984; Rosenberg et al., 1985).
There are also few data on lethal potency of Duvernoy's secretions from M.
monspessulanus . Rosenberg et al. (1985) reported a murine i.v. LD 50 of 6.5 mg/kg
and noted that mice injected with lethal doses exhibited “paralysis.”
Gel filtration chromatography of M. monspessulanus secretion yielded two lethal
fractions (Rosenberg et al., 1985). One fraction (“IIIA”) contained several compo-
nents with molecular masses of 13 or 17 kDa. This fraction contained PLA 2 activity
and had a murine i.v. LD 50 of 2.75 mg/kg (Rosenberg et al., 1985). The other lethal
fraction (“IV”) lacked PLA 2 activity, contained components with molecular masses
of approximately 13 kDa, and had a murine i.v. LD 50 of 4.5 mg/kg (Rosenberg
et al., 1985). An additional non-lethal fraction contained most of the phosphodiester-
ase activity detected in the secretion (Rosenberg et al., 1985). Further fractionation
utilizing gel filtration and cation exchange procured a lethal hemorrhagic toxin (“frac-
tion CM-6”) with molecular mass of 24 kDa and a murine i.v. LD 50 of 1.0 mg/kg.
This toxin lacked proteolytic and procoagulant activities. Although negative in intra-
dermal hemorrhagic assay, lethal and sublethal doses produced pulmonary hemorrhage
in mice (Rosenberg et al., 1992).
4.4.2.4 Does M. monspessulanus Produce Neurotoxic Envenoming?
Among more than 70 medically documented bites thought to have been inflicted by
this species, only three have reported neurotoxic effects ( Table 4.1 ). A 36-year-old
herpetologist was bitten by a large M. monspessulanus in southern France (Pommier
and de Haro, 2007). Ninety minutes after the bite, his vision became blurred; some
hours later, when he was admitted to the Poison Control Center in Marseille, there was
bilateral ptosis, partial oculomotor paralysis, and loss of visual accommodation—all of
which resolved over the next 6 days. This is convincing evidence of neurotoxic enven-
omation. Although there are a limited number of cases, it is likely several other people
bitten by this species have developed similar features (Gonzáles, 1979, 1982).
Although the identification of the snake in the aforementioned case is not in ques-
tion, consideration must be given to the lack of verified identity of the culprit snake in
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