R. Shires et al., MICROTUBULE SYSTEMS ASSOCIATED WITH THE SEPTATE JUNCTIONS OF THE GILLCELLS OF 4 GAMMARID AMPHIPODS, Tissue & cell, 27(1), 1995, pp. 3-12
The microtubular systems associated with the septate junctions of the
gill epithelial cells of four species of gammarid amphipod are describ
ed, The four species examined included two relatively stenohaline mari
ne forms, Chaetogammarus marinus and Gammarus locusta; a highly euryha
line species, Gammarus duebeni, and a stenohaline freshwater species,
Gammarus pulex, Of these amphipods, G. locusta and C. marinus maintain
only a limited osmotic gradient between their haemolymph and the medi
um and have a poorly developed junctional microtubular system; G. pule
x has haemolymph which is some 300 mOsmol hypertonic to freshwater and
has a well ordered system of microtubules on both sides of fairly lon
g septate junctions; G. duebeni from brackish water tend to have a som
ewhat shorter length of septate junctions lined by one or occasionally
by a double row of microtubules, The most complex junctional microtub
ular systems are shown by specimens of the freshwater race of G. duebe
ni celticus which have been acclimated to seawater, These can take the
form of multiple arrays in which some microtubules are linked to the
plasma membrane by dense strands, It is suggested that these findings
are consistent with the hypothesis that one role of these microtubules
is to provide mechanical stability to enable the integrity of the sep
tate junctions to be maintained during osmotic stress,