1978 Volume 29 Issue 2 Pages 185-196
Scanning electron microscopy revealed that the spines of the slug moth caterpillar, Parasa consocia had no opening at the pointed ends, differing from the results reported by many investigators based on light microscopic observations. Fine structure of the spicules and their sockets on the 8th and 9th dorsal segments of the last instar larva was also described. PBS extracts from the spines and spicules were fractionated by a single hollow fiber concentrator (SHFC). The inner fluid in SHFC, containing substances with molecular weights higher than 15,000 (HM) was further fractionated through a Sephadex G-100 column, while the outer fluid containing lower molecular substances (LM) was fractionated through a Sephadex G-50 column. 1. Injection of crude venom from the spines and spicules into the tail vein of mice made them squeak and bite at the injected area due probably to local pains, followed by crouching posture and shiver for a few hours. Paralysis was observed at their hind legs when injected with the venom subcutaneously. 2. Thin-layer chromatography revealed the presence of histamine in both the venoms from the spines and spicules. 3. HMs and LMs separated from the crude venoms of the spines and spicules exhibited positive skin reactions in man by scratch method : Erythema and edema or wheal were the common symptoms produced by all of these fractions tested. Severe recurrent pains were produced by the HMs a few minutes after application. The pains were relieved within several hours, but contact stimuli to the applied area of the skin produced the recurrent pains for a few days. Though the LM from the spine venom also showed pain-producing activity, it differed from the HMs in its rapid action and shorter duration. 4. Each of the HMs from the spine and spicule venoms was separated into 3 fractions (HM-I-III), by column chromatography : HM-Is had a wheal producing activity in the skin test. HM-IIs had activities to produce severe pain and to contract smooth muscle of the isolated guinea pig ileum. The contraction induced by the two HM-IIs differed from that by histamine in that the former took longer time before the onset and showed longer duration of the contraction after several washes with Tyrode's solution; it also differed from the contraction caused by bradykinin in that the former showed tachyphylaxis. Moreover, self-movement of the ileum was increased during or after the contraction and it continued till the intra-ileac contents were thoroughly ejected. Contraction activity of the spine HM-II might be due to two substances, HM-IIa and HM-IIb. Stimulating effect of the spine HM-II on the polymodal receptor of dog testis was kept longer than that of bradykinin. Vascular permeability in guinea pig skin was also increased by the spine HM-I-III. 5. The LM from the spines was found to contain two active substances; one was histamine and the other was protein or polypeptide (LM-I) with a molecular weight of several thousands. LM-I possessed activities such as pain-producing, ileum-contracting without tachyphylaxis, and vascular permeability-increasing. From these results, it was suggested that LM-I might be a kinin-like substance.
