RESUMO
Presence of a toxin in the salivary glands of the marine snail Cymatium intermedius that targets nicotinic acetylcholine receptors. Toxicon 36, 25-29, 1998.-We present evidence of a neurotoxin from the salivary glands of Cymatium intermedius that displays acetylcholine-like effects on vertebrate (mouse ileum) and invertebrate (molluscan smooth muscle; molluscan heart; leech body wall) tissues. These effects were completely blocked by (+)-tubocurarine (10-100 muM) but not by atropine (up to 200 muM) suggesting that the toxin targets nicotinic-like acetylcholine receptors. This affirms the proposal that this genus may overcome their prey with a paralytic secretion.
Assuntos
Toxinas Marinhas/análise , Músculos/efeitos dos fármacos , Neurotoxinas/análise , Receptores Nicotínicos/efeitos dos fármacos , Glândulas Salivares/química , Caramujos/química , Animais , Bioensaio , Bivalves/efeitos dos fármacos , Sanguessugas/efeitos dos fármacos , Toxinas Marinhas/farmacologia , Camundongos , Neurotoxinas/farmacologiaRESUMO
We report here the presence of a bioactive compound in the secretion of the accessory salivary glands (ASGs) of Nucella lapillus. We have purified the compound using HPLC and identified it as serotonin by mass spectrometry, UV spectroscopy, HPLC and capillary electrophoresis. Serotonin was not found in the secretions of the acinous salivary glands or the hypobranchial gland. The amount of serotonin in the secretion of the ASGs does not show seasonal or regional variation.
Assuntos
Venenos de Moluscos/química , Serotonina/isolamento & purificação , Caramujos/metabolismo , Animais , Cromatografia Líquida de Alta Pressão , Eletroforese , Espectrometria de Massas , Músculos/efeitos dos fármacos , Glândulas Salivares/metabolismo , Serotonina/farmacologia , Espectrofotometria UltravioletaRESUMO
A new opto-electronic method has been used to measure spontaneous eye movements in a lightly restrained unanaesthetized marine teleost fish (Parore). The normal scanning pattern of eye movement is similar to that previously described in goldfish. The effects of cooling on eye movements were investigated by 2 degrees C step changes down from ambient temperature (13-14 degrees C). Lowered temperature altered the scanning pattern, decreased saccade velocity, increased mean saccade amplitude and impaired the ability of the fish to hold the eye stationary between saccades. All eye movements stopped at temperatures around 6 degrees C, but could be restored by subsequent warming.