@article{9edce7d7fb704a7f9efd51957b90d456,
title = "Ultrastructure of a histaminergic synapse in Aplysia",
abstract = "The ultrastructure of histaminergic synaptic terminals was studied by the means of intrasomatic injection of horseradish peroxidase into the identified histaminergic neuron C2 of Aplysia. The axonal tree of C2 was found to consist, in part, of varicosities that display putative release sites similar in morphology to those described in other neurons in Aplysia. The varicosities contain at least two populations of vesicles: a conspicuous class of large vesicles with an electron-dense core that almost fills the entire vesicle and a heterogeneous class of large and small electron-lucent vesicles. The small lucent vesicles preferentially cluster near active zones.",
keywords = "Aplysia, histamine, synapse, vesicle",
author = "Bailey, {Craig H.} and Chen, {Mary C.} and Weiss, {Klaudiusz R.} and Irving Kupfermann",
note = "Funding Information: Increasing evidence indicates that histamine is a neurotransmitter in the central nervous system of vertebratesI0,15. However, the lack of suitable techniques to specifically label histaminergic neurons has hindered studies of tiffs class of cells. For this reason a number of basic questions remain unanswered regarding the morphology of histaminergic synapses. For example, are histaminergic terminals similar to other aminergic terminals, or do they possess unusual features, such as the large granules characteristic of non-neuronal histamine-containing cells4,7,222 The technical problems of studying histaminergic neurons are circumvented, in part, in invertebrates in which individual histaminergic neurons can be identified by their biochemical properties is,20 as well as by their size, position, and characteristic synaptic responses in follower cells12,21,~ 3. The most completely characterized histaminergic neuron is C2, located in the cerebral ganglion of the marine mollusc, Aplysia. Activity of tiffs neuron produces direct synaptic potentials in a number of follower cells in the cerebral ganglion lz,zl,2s. In some instances, these synaptic potentials have unusual features, such as very long time course, or non-linear voltage dependence. We have studied the ultrastructure of possible synapses made by C2, using intracellular injection of horse-radish peroxidase (HRP) as a marker substance. Experiments were performed on Aplysia californica (50-100 g) obtained from the Pacific Bio-Marine Supply Co., * To whom all correspondence should be addressed at: Center for Neurobiology and Behavior, College of Physicians and Surgeons, Columbia University, New York, NY 10032, U.S.A. ** Supported by NSF BNS 7824476 and I. T. Hirsekl Career Scientist Award to C.H.B., Research Scientist Development Award KOZMH 003009 to K.K.W. and Grants GM 23540 and MH 35564.",
year = "1982",
month = apr,
day = "22",
doi = "10.1016/0006-8993(82)90784-3",
language = "English",
volume = "238",
pages = "205--210",
journal = "Brain Research",
issn = "0006-8993",
publisher = "Elsevier B.V.",
number = "1",
}