Cellular Aspects of the Control of Physiological Color Changes in Crustaceans |
| |
Authors: | FINGERMAN MILTON |
| |
Affiliation: | Department of Biology, Tulane University Neto Orleans, Louisiana 70118 and Marine Biological Laboratory Woods Hole, Massachusetts 02543 |
| |
Abstract: | SYNOPSIS. Red chromatophores(erythrophores) of the prawn, Palaemonetesvulgaris, are controlled by pigmentdispersing and -concentratinghormones. Recent experiments on the modes of action of thesehormones are described, followed by a theory which satisfactorilyexplains the data. Red pigment-concentrating hormone is dependentupon sodium ions for a strong response to occur. There is asimilar dependency of red pigmentdispersing hormone uponcalcium ions. Ouabain inhibits the response to red pigmentconcentratinghormone; tetrodotoxin enhances it. Erythrophores with maximallydispersed pigment had a transmembrane potential of 55±15mv inside negative in one series of experiments and 56±4mv in another. No appreciable changes in permeability occurwhen depolarizing and hyperpolarizing currents are passed througha microelectrode within the chromatophore. Red pigmentconcentratinghormone causes hyperpolarization of the transmembrane potential.The magnitude of hyperpolarization is directly related to thedegree of pigment concentration. Adenosine 3`;, 5`-monophosphate(cyclic AMP) causes dispersion of the red pigment but has nopigment-concentrating effect. The primary action of red pigmentconcentratinghormone is most likely stimulation of a pump which exchangessodium ions from inside the chromatophore with potassium ionsfrom the outside, whereas red pigment-dispersing hormone quitelikely stimulates entry of calcium ions into the chromatophore. |
| |
Keywords: | |
本文献已被 Oxford 等数据库收录! |
|