Aplysia

Pasture, A., et al. Stmctural alignment and analysis of two distantly related proteins Aplysia limacina myoglobin and sea lamprey globin. Proteins 4 240-250, 1988. 

Miller, A. L., et al. (1991). Imaging free calcium in cultured Aplysia bag cell neurons. Biol. Bull. 181 325. 

It is most probable that sleep and waking stem from an inherent cycle of neuronal activity that can be influenced dramatically by changes in sensory stimulation. This is demonstrable not only in humans and laboratory animals, but also in invertebrates. Thus, while we cannot be sure that other animals sleep in the same way that we do, they do show a circadian cycle of motor activity. In some (nocturnal) species, such as the rat, this activity is actually highest during darkness. Even aplysia, the sea hare, has such a rhythm but this is more like that of humans in being maximally active during daylight (diurnal). 

Giant neuron of Aplysia californica Nj closed-end all-glass microelectrode Na- 40.3 mM 146)... 

Detailed studies on the metabolism of arachidonic acid (AA) in the nervous system of the opisthobranch mollusc Aplysia califomica were carried out [21]. A. califomica provides a very useful model for neurobiological studies since its... 

Fig. 2. Arachidonic acid metabolites identified in Aplysia californica nervous tissue...

As far as the biological action in Aplysia neurons of hepoxilin A3 and 12-kete is concerned, application of hepoxilin A3 to L14 neurons results in a marked membrane hyperpolarization, accompanied by an increased membrane ion conductance, while application of 12-kete to the same cells produced... 

While little biosynthetic information is available, it has been suggested [38] that 25 and 26 may be formed from AA (24) and EPA (14) via a cyclization mechanism (Scheme 3) similar to that which forms trans-cyclopropyl-containing diol 28 upon treatment of linoleic acid with performic acid [40]. An alternative biogenetic mechanism (Scheme 4), based upon that proposed for the structurally related red algal metabolites constanolactone A and B [41], would involve the formation and opening of an allylic epoxide intermediate created as a result of a 15-/ -LPO acting on either AA or EPA. Related compounds have been isolated from the coral Plexaura homomalla and the mollusc Aplysia kurodai (see below). 

The following generalized protocol is an adaptation for the labeling of 15 nm gold particles with Aplysia gonad lectin, as described by Benhamou et al., 1988. Each lectin-gold preparation will have its own unique pH optimum and ratio of lectin-to-gold for the absorption process. 

Si, K., Giustetto, M., Etkin, A. et al. A neuronal isoform of CPEB regulates local protein synthesis and stabilizes synapse-specific long-term facilitation in aplysia. Cell 115 893-904, 2003. 

The release of neuropeptides generally requires a more intense stimulus than that required for release of fastacting classical neurotransmitters. The more intense stimulus presumably results in more entry of Ca2+ into the presynaptic terminal, allowing Ca2+ to diffuse from its entry site to the LDCVs (Figs 18-3,18-4). As a result, the contribution of peptides vs. fast-acting conventional neurotransmitters to signaling can vary with the pattern of stimulation. For example, in Aplysia, several identified... 

Heller, E., Kaczmarek, L. K., Hunkapiller, M. H., Hood, L. E., and Strumwasser, F. (1980) Purification and primary structure of two neuroactive peptides that cause bag cell afterdischarge and egg laying in Aplysia. Proc. Natl. Acad. Sci. USA, 77 2328-2332. 

Jung, D., and Moore, G. P. (1966) lnterspike-interval fluctuations in Aplysia pacemaker neurons. Biophys. J., 6 411-434. 

Kupfermann, I., and Kandel, E. R. (1970) Electrophysiological properties and functional interconnections of two symmetrical neurosecretory clusters (bag cells) in abdominal ganglion of Aplysia. J. Neurophysiol.. 33 865-876. 

Hawkins, R. D., Abrams, T. W., Carew, T. J., and Kandel, E. R. (1983) A cellular mechanism of classical conditioning in aplysia Activity-dependent amplification of presynaptic facilitation. Science, 219 400-405. 

Johnson PM, Kicklighter CE, Schmidt M, Kamio M, Yang HC, Elkin D, Michel WC, Tai PC, Derby CD (2006) Packaging of chemicals in the defensive secretory glands of the sea hare Aplysia califomica. J Exp Biol 209 78-88... 

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