On the discrepancy between whole-cell and membrane patch mechanosensitivity in Xenopus oocytes

Yong Zhang, Owen P. Hamill

Research output: Contribution to journalArticle

56 Scopus citations

Abstract

1. Mechanical stimulation of voltage-clamped Xenopus oocytes by inflation, aspiration, or local indentation failed to activate an increase in membrane conductance up to the point of causing visible oocyte damage. 2. The absence of mechanosensitivity is not due to the vitelline membrane, rapid MG channel adaptation or tension-sensitive recruitment of new membrane. 3. Membrane capacitance measurements indicate that the oocyte surface area is at least 5 times larger than that predicted assuming a smooth sphere. We propose that this excess membrane area provides an immediate reserve that can 'buffer' membrane tension changes and thus prevent MG channel activation. 4. High-resolution images of tightly sealed patches and patch capacitance measurements indicate a smooth membrane that is pulled flat and perpendicular across the inside of the pipette. Brief steps of pressure or suction cause rapid and reversible membrane flexing and MG channel activation. 5. We propose that changes in membrane geometry induced during cell growth and differentiation or as a consequence of specific physiological and pathological conditions may alter mechanosensitivity of a cell independently of the intrinsic properties of channel proteins.

Original languageEnglish (US)
Pages (from-to)101-115
Number of pages15
JournalJournal of Physiology
Volume523
Issue number1
DOIs
StatePublished - Feb 15 2000

ASJC Scopus subject areas

  • Physiology

Fingerprint Dive into the research topics of 'On the discrepancy between whole-cell and membrane patch mechanosensitivity in Xenopus oocytes'. Together they form a unique fingerprint.

  • Cite this