Stimulation of an individual cell with peptide hormone in a prescribed region of its plasma membrane results in a compartmentalized cyclic AMP-dependent protein kinase response.
This work describes the stimulation by a peptide hormone of an individual cell in a prescribed region of its plasma membrane. When Leydig cells were stimulated via a section of membrane tightly sealed to an electrode containing LH, a very localized area exhibited the morphological change known as 'rounding up', which is a cyclic AMP-dependent protein kinase-mediated response. This localized stimulation did not produce a wider response through intracellular, intermembranous or extracellular signals. Each individual cell responded to peptide stimulation gradually, with an increase over time and with dose. In contrast, when the stimulation was accomplished using a non-hydrolysable cyclic AMP analogue in the patch electrode, a general response throughout an individual cell was produced. Locally stimulated peptide hormone receptors, adenylate cyclases and cyclic AMP-dependent protein kinases appear to be closely associated so that second messenger production and the effects it mediates are compartmentalized.
Podesta
E J
EJ
Worcester Foundation for Experimental Biology, Shrewsbury, Massachusetts 01545.
Solano
A R
AR
Lemos
J R
JR
D002451:Cell Compartmentation; D002462:Cell Membrane / Q000378:metabolism* / Q000648:ultrastructure; D004566:Electrodes; D007700:Kinetics; D007984:Leydig Cell Tumor; D007986:Luteinizing Hormone / Q000494:pharmacology*; D008855:Microscopy, Electron, Scanning; D011494:Protein Kinases / Q000378:metabolism*; D015290:Second Messenger Systems; D014407:Tumor Cells, Cultured
D007986:Luteinizing Hormone; D011494:Protein Kinases