|
| |
|
|
|
|
||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | ||||
Journal of Experimental Biology, Vol 155, Issue 1 261-273, Copyright © 1991 by Company of Biologists
JOURNAL ARTICLES |
S Catarsi and M Brunelli
Dipartimento di Fisiologia e Biochimica, Universita di Pisa, Italy.
In T sensory neurones of the leech, a train of impulses elicited by intracellular electrical stimulation leads to an after-hyperpolarization of up to 30 mV, mainly due to the activation of the electrogenic Na+/K(+)-ATPase but partly to a Ca2(+)-activated K+ conductance. It was found that serotonin reversibly reduced the amplitude of this after-hyperpolarization. We investigated the mechanism of action of serotonin and found: (1) after inhibition of the Ca2(+)-activated K+ conductance with BaCl2 or CdCl2, serotonin was still able to reduce the after-hyperpolarization; (2) when penetration of T cells with microelectrodes leaking sodium was preceded by serotonin perfusion of the ganglia, the normal hyperpolarization due to the activation of the electrogenic pump was converted to a depolarization; (3) after long-lasting perfusion with K(+)-free saline solution (which inhibits the Na+/K+ pump), the application of CsCl caused repolarization by reactivating the electrogenic ATPase; serotonin slowed and reduced this repolarization; (4) serotonin potentiated the depolarization of T neurones caused by the inhibition of the Na+/K+ pump following cooling of ganglia and depressed the hyperpolarization after rewarming to room temperature. These data taken together suggest that serotonin directly inhibits the Na+/K+ electrogenic pump.
This article has been cited by other articles:
|
|
 |
|
  A.-E. Tobin and R. L. Calabrese Endogenous and Half-Center Bursting in Morphologically Inspired Models of Leech Heart Interneurons J Neurophysiol, October 1, 2006; 96(4): 2089 - 2106. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A.-E. Tobin and R. L. Calabrese Myomodulin Increases Ih and Inhibits the Na/K Pump to Modulate Bursting in Leech Heart Interneurons J Neurophysiol, December 1, 2005; 94(6): 3938 - 3950. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. D. Burrell and C. L. Sahley Serotonin Mediates Learning-Induced Potentiation of Excitability J Neurophysiol, December 1, 2005; 94(6): 4002 - 4010. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Scuri, R. Mozzachiodi, and M. Brunelli Role for Calcium Signaling and Arachidonic Acid Metabolites in the Activity-Dependent Increase of AHP Amplitude in Leech T Sensory Neurons J Neurophysiol, August 1, 2005; 94(2): 1066 - 1073. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
R. Scuri, R. Mozzachiodi, and M. Brunelli Activity-Dependent Increase of the AHP Amplitude in T Sensory Neurons of the Leech J Neurophysiol, November 1, 2002; 88(5): 2490 - 2500. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. D. Burrell, C. L. Sahley, and K. J. Muller Non-Associative Learning and Serotonin Induce Similar Bi-Directional Changes in Excitability of a Neuron Critical for Learning in the Medicinal Leech J. Neurosci., February 15, 2001; 21(4): 1401 - 1412. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Mar and P. Drapeau Modulation of Conduction Block in Leech Mechanosensory Neurons J. Neurosci., July 15, 1996; 16(14): 4335 - 4343. [Abstract] [Full Text] [PDF]
|
|
