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Neurosecretion pp 199-205 | Cite as

Electrical Attributes of Neurosecretory Terminals and Their Relationship to Secretion

  • E. L. Stuenkel
  • I. M. Cooke

Abstract

This article briefly reviews the electrical attributes of nerve terminals and of their relationship to secretion for a neurosecretory system in crabs termed the X-organ sinus gland (XOSG). This neurosecretory system is a purely peptidergic secretory system whose hormonal secretions are known to influence or govern nearly all physiologic and homeostatic processes (reviews, Cooke and Sullivan, 1982; Keller, 1983). A portion of the system termed the sinus gland (SG) is a discrete spherical (c. 1.5 mm. diameter) structure composed of an extensive arborization of axon varicosities and terminals together with glial and supportive cells which surround a network of hemolymph sinuses. The cell soma, where axons project to and compose the sinus gland, are located in a cluster named the X-organ. The relatively large size of individual axon terminal dilatations in certain species of crabs (e.g., Cardisoma carnifex. Podoohthalamus vigil) is novel among peptidergic neurosecretory systems. The terminals in these species are of sufficient size (up to 30 um) to have allowed extensive investigation with intracellular microelectrodes in both in situ and in vitro preparations (reviews, Cooke and Stuenkel, 1985; Stuenkel and Cooke, 1988). Recently a preparation of dissociated terminals from the sinus gland has been developed and investigated with the various recording configurations of the patch clamp technique (Lemos et al., 1986). A number of electrical and secretory attributes of the peptidergic terminals have been characterized including: 1) the ionic dependence of regenerative activity, 2) ‘whole terminal’ patch clamp analysis of voltage dependent macroscopic ionic currents and of two novel cation channel types and 3) correlation of terminal electrical behaviour with hormonal secretion monitored simultaneously under different secretory regimes.

Keywords

Crustacean Hyperglycemic Hormone Slope Conductance Neurosecretory System Sinus Gland Terminal Preparation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1988

Authors and Affiliations

  • E. L. Stuenkel
    • 1
  • I. M. Cooke
    • 2
  1. 1.Department of PhysiologyUniversity of CaliforniaSan FranciscoUSA
  2. 2.Bekesy Laboratory of NeurobiologyHonoluluUSA

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