A hyperpolarization-activated inward current alters swim frequency of the pteropod mollusk Clione limacina

作者：Pirtle Thomas J^*; Willingham Kyle; Satterlie Richard A

来源：Comparative Biochemistry and Physiology A-Molecular & Integrative Physiology, 2010, 157(4): 319-327.

DOI：10.1016/J.cbpa2010.07.025

• Clione limacina
• Central pattern generator
• Hyperpolarization-activated inward current
• Postinhibitory rebound
• lnterneurons
• Serotonin-induced

The pteropod mollusk, Clione limacina, exhibits behaviorally relevant swim speed changes that occur within the context of the animal's ecology Modulation of C limacina swimming speed involves changes that occur at the network and cellular levels. Intracellular recordings from interneurons of the swim central pattern generator show the presence of a sag potential that is indicative of the hyperpolarization-activated Inward current (I(h)) -Here we provide evidence that I(h) in primary swim interneurons plays a role in C. limacina swimming speed control and may be a modulatory target. Recordings from central pattern generator swim interneurons show that hyperpolarizing current injection produces a sag potential that lasts for the duration of the hyperpolarization, a characteristic of cells possessing I(h). Following the hyperpolarizing current injection, swim interneurons also exhibit postinhibitory rebound (PIR). Serotonin enhances the sag potential of C limacina swim interneurons while the I(h) blocker. ZD7288, reduces the sag potential. Furthermore, a negative correlation was found between the amplitude of the sag potential and latency to PIR. Because latency to PIR was previously shown to influence swimming speed, we hypothesize that I(h) has an effect on swimming speed. The I(h) blocker. ZD7288, suppresses swimming in C limacina and inhibits serotonm-induced acceleration, evidence that supports our hypothesis.

• 出版日期2010-12