STIMULATION OF THE PALATAL CHEMORECEPTORS OF THE CARP BY MIXED SOLUTIONS OF ACID AND SALT

DOI Web Site PubMed

この論文をさがす

説明

The stimulating effect of NaCl added to HCl solution upon the palatal chemoreceptors of the carp was studied by recording the responses from the palatine nerve innervating the palatal organ.<BR>In summated multifiber responses, the addition of NaCl at relatively weak concentrations enhanced the effect of HCl solutions. The effect of NaCl of a fixed concentration varied with varying concentrations of HCl, yielding a shift of the response-HCl concentration curve toward a lower concentration range. The enhancing effect of NaCl depended also on its own concentration. The response at a fixed HCl concentration increased as the concentration of NaCl was raised. At high concentrations of NaCl, however, the response did not increase with a rise in the concentration of NaCl in spite of the fact that a rapid increase of the response to plain NaCl solutions was observed at that concentration range.<BR>Some fibers were found that did not respond to NaCl but responded to mixtures of NaCl and HCl with higher impulse frequencies than to acid solutions alone. Other fibers, though responding well to NaCl, showed only a poor response to mixtures of NaCl and HCl. These fibers did not respond at all to plain acid solutions.<BR>The effects of NaBr, NaClO4, NaI, NaNO3, NaSCN, Na2SO4, KCl, LiCl, NH4Cl, RbCl, choline chloride, CaCl2, MgCl2, and MgSO4 added to HCl solutions on the summated response were also studied. All of these salts except MgSO4 and Na2SO4 enhanced the response to HCl about equally. The sulphate appeared to have a depressant effect.<BR>These results suggest that the enhancement of the response to HCl by NaCl and other salts may be related to the activity of the acid receptor rather than the salt receptor. In addition, the results with NaCl suggest the presence of salt receptors whose responses to NaCl are depressed in the presence of HCl or at a low pH.<BR>The stimulating effects of H2SO4, HCl, and HNO3 were compared by recording the responses from multifiber strands: H2SO4 was found to be less effective than the other two monobasic acids over the pH range used.

収録刊行物

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ