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Effect of black widow spider venom on the cockroach heart
Reviews
209
CooxE, J. A. L., RorH, V. D. and Mtu,>at, F. H. (Respectively from : Department of Entomology, American Museum of Natural History; Southwestern Research Station, Portal Arizona; and Nassau County Medical Center, East Meadow, N.Y .) . The urticating hairs of theraphosid spiders. .ten . Ms. Novit. No . 2498 . July, 1972, pp . 1~3. FOtrn nrrFS of urticating hairs were found on the dorsal surface of the abdomen in representatives of four subfamilies of NewWorld spiders belonging to the family Theraphosidae (`tarantulas'). The urticarious effect of these hairs, which sewn to be wholly defensive in nature, seems to be due solely to mechanical irritation . These hairs, which were classifiod on basis of the size, numbers and directional orientation of the barbs and denticles with which they are armed, were described and illustrated with the aid of a scanning electron microscope . None of the theraphosid spiders examined possessed more than two hair types. There was considerable variation among species in this respect, and the authors are of the opinion that these urticarial hairs may have potential value in the confused field of theraphosid systematics. Effects of contact of these hairs on mice and other experimental animals was described. T)u: authors, who are well qualified in thin field, noted that possession of urticarial hairs semis linked with the relative docility of moat New World theraphoaids who posecas them, and absence of these hairs is characteristic of more aggressive African and Oriental species, as well as some of the New World theraphosids who lack them . The publication is beautifully illustrated and extremely well written. It would be interesting to determine whether repeated contact with the urticating hairs of these spiders will evoke an allergenic response. This reviewer has talked with a scientist in Brazil who mentioned that he had been dealing with colonies of theraphosid spiders for years and would devebp intense urticaria on even slight contact with them . H.L .K .
MNOw, G., Bsn~nvt,
S. and C~atu, O. (Istituto Superiors de Sanita, Rome, Italy) . Effect of black widow spider venom on the cockroach heart. J. Insect Physlol. 18, 913, 1972 . BLOCiutse of the heartbeat of the oodu~oach Periplarleta an~ericmta occurred following inaction of crude venom gland extraà of the black widow apidar, injection of gland lumen venom of this species, and after bites by apidaa, (Iatrodectws mactmu tredecbnguttatus). The authors suggest that the cardiac block is due to impairment of either the cardiac nerve ganglia function or the myocardial neuromuscularjunctions, or of both. It was shown that antiserum prepared by immunizûtg sheep, when inwbated Ge vitro with high doses of venom gland éxtract or gland lumen venom, complGely neutralized the heart-blocking effect and the patalyt~ effect of each of these materials. On the other hand, it was found that although heart activity of preparations blockedwith doses of crude venom gland extract could be restored by antiserum, restoration of heart beat in preparations blocked by gland lumen venom could not be obtained . When crude venom gland extract and gland lumen venom were injected and followed by injections of antiserum, only s few roaches recovered. The authors speculate that in these In vfvn experiments, the toxicity of the injected materials might have been modified by the natural defenses of the intact organism . They also wondered whether the nerve connections of the central nervous system with the heart and its extrinsic musculature might have been targets for the toxic materials and reached with greater di6kvlty by the injected antiserum. H.L .K .
Ptuctcesti, A., MsnCOF, J. C. and Tt~vnutar, A. D. Paralytk Shel(fsrle Poisoning In Eastern Canada. Fisheries Research Hoard of Canada, Bull . 71, Ottawa, 1971, 88 p. T~ trotvoaturx deals with the history of paralytic shellfish poisoning (PSP), the clinical syndrome problems related to the toxicity of shellfish and thecausative organism, the toxin, sad related topics . Dr. Tennaat contributed the data on the measurement of shellfish toxicity. Dr. Medcof provided the sections on poisoning, the taudcity of ahellßah and the control programs ; and Dr. Prackash prepared the material on the cauaetive organiuns, the mechanisms of toxin accumulation and elimination, the nature of the toxin, and the detoxification of shellfish . While most of the data are related to the problem of 1?SP in eastern Canada, the authors have included sufficient relevant material to make the text of considerable interest and value to anyone working on this form of poisoning. 710XJCON 1973 Yal. 11.
209
CooxE, J. A. L., RorH, V. D. and Mtu,>at, F. H. (Respectively from : Department of Entomology, American Museum of Natural History; Southwestern Research Station, Portal Arizona; and Nassau County Medical Center, East Meadow, N.Y .) . The urticating hairs of theraphosid spiders. .ten . Ms. Novit. No . 2498 . July, 1972, pp . 1~3. FOtrn nrrFS of urticating hairs were found on the dorsal surface of the abdomen in representatives of four subfamilies of NewWorld spiders belonging to the family Theraphosidae (`tarantulas'). The urticarious effect of these hairs, which sewn to be wholly defensive in nature, seems to be due solely to mechanical irritation . These hairs, which were classifiod on basis of the size, numbers and directional orientation of the barbs and denticles with which they are armed, were described and illustrated with the aid of a scanning electron microscope . None of the theraphosid spiders examined possessed more than two hair types. There was considerable variation among species in this respect, and the authors are of the opinion that these urticarial hairs may have potential value in the confused field of theraphosid systematics. Effects of contact of these hairs on mice and other experimental animals was described. T)u: authors, who are well qualified in thin field, noted that possession of urticarial hairs semis linked with the relative docility of moat New World theraphoaids who posecas them, and absence of these hairs is characteristic of more aggressive African and Oriental species, as well as some of the New World theraphosids who lack them . The publication is beautifully illustrated and extremely well written. It would be interesting to determine whether repeated contact with the urticating hairs of these spiders will evoke an allergenic response. This reviewer has talked with a scientist in Brazil who mentioned that he had been dealing with colonies of theraphosid spiders for years and would devebp intense urticaria on even slight contact with them . H.L .K .
MNOw, G., Bsn~nvt,
S. and C~atu, O. (Istituto Superiors de Sanita, Rome, Italy) . Effect of black widow spider venom on the cockroach heart. J. Insect Physlol. 18, 913, 1972 . BLOCiutse of the heartbeat of the oodu~oach Periplarleta an~ericmta occurred following inaction of crude venom gland extraà of the black widow apidar, injection of gland lumen venom of this species, and after bites by apidaa, (Iatrodectws mactmu tredecbnguttatus). The authors suggest that the cardiac block is due to impairment of either the cardiac nerve ganglia function or the myocardial neuromuscularjunctions, or of both. It was shown that antiserum prepared by immunizûtg sheep, when inwbated Ge vitro with high doses of venom gland éxtract or gland lumen venom, complGely neutralized the heart-blocking effect and the patalyt~ effect of each of these materials. On the other hand, it was found that although heart activity of preparations blockedwith doses of crude venom gland extract could be restored by antiserum, restoration of heart beat in preparations blocked by gland lumen venom could not be obtained . When crude venom gland extract and gland lumen venom were injected and followed by injections of antiserum, only s few roaches recovered. The authors speculate that in these In vfvn experiments, the toxicity of the injected materials might have been modified by the natural defenses of the intact organism . They also wondered whether the nerve connections of the central nervous system with the heart and its extrinsic musculature might have been targets for the toxic materials and reached with greater di6kvlty by the injected antiserum. H.L .K .
Ptuctcesti, A., MsnCOF, J. C. and Tt~vnutar, A. D. Paralytk Shel(fsrle Poisoning In Eastern Canada. Fisheries Research Hoard of Canada, Bull . 71, Ottawa, 1971, 88 p. T~ trotvoaturx deals with the history of paralytic shellfish poisoning (PSP), the clinical syndrome problems related to the toxicity of shellfish and thecausative organism, the toxin, sad related topics . Dr. Tennaat contributed the data on the measurement of shellfish toxicity. Dr. Medcof provided the sections on poisoning, the taudcity of ahellßah and the control programs ; and Dr. Prackash prepared the material on the cauaetive organiuns, the mechanisms of toxin accumulation and elimination, the nature of the toxin, and the detoxification of shellfish . While most of the data are related to the problem of 1?SP in eastern Canada, the authors have included sufficient relevant material to make the text of considerable interest and value to anyone working on this form of poisoning. 710XJCON 1973 Yal. 11.