Showing papers by "University of Adelaide published in 1981"
592 citations
TL;DR: Hybridization of Chinese Spring wheat and Betzes barley using wheat as the female parent gave only 1·3 per cent seed set compared to 15·4 per cent obtained with the reciprocal cross made earlier, and only one of the 20 F1 hybrids obtained possessed the normal complement of 28 chromosomes.
Abstract: Hybridization of Chinese Spring wheat and Betzes barley using wheat as the female parent gave only 1·3 per cent seed set compared to 15·4 per cent obtained with the reciprocal cross made earlier. Furthermore, only one of the 20 F1 hybrids obtained possessed the normal complement of 28 chromosomes. The others had unusual chromosome numbers ranging from 21-36 in different plants. The 28-chromosome normal hybrid was backcrossed to wheat to produce a heptaploid in the first backcross generation (BC1) and subsequently monosomic (21 II + 1 I) and double monosomic (21 II + 1 I + 1 I) additions of barley chromosomes to wheat were isolated in the BC2 generation. The monosomic additions could be divided into five different phenotypic groups and disomic additions were isolated from among their progeny with a very low frequency (0·63 per cent). However, some monotelo-disomic additions (21 II +1t II) obtained from the progeny of selfed monosomies yielded both disomic and ditelosomic additions in their progeny with a much higher frequency. A sixth addition line was obtained independently from three unusual F1 hybrids exhibiting 22 I, 21 I + 1 II and 25 I + 1 III at meiosis. Altogether six of the seven possible disomic additions and seven of the 14 ditelosomic additions of barley chromosomes to wheat have been produced. The chromosome 5 addition could not be obtained in a disomic form because the plants carrying this chromosome are self-sterile. The addition lines were initially characterized by their morphological differences from the wheat parent, and subsequently from isozyme studies and heterochromatic banding (N-banding) of chromosomes. Most of these lines showed more asynapsis at meiosis than the wheat parent and all, except addition line 4, were less fertile than the wheat parent.
367 citations
TL;DR: In this paper, the core values and cultural identity are discussed in the context of ethnic and racial studies, and the authors propose a set of core values for each ethnic group, including:
Abstract: (1981). Core values and cultural identity. Ethnic and Racial Studies: Vol. 4, No. 1, pp. 75-90.
311 citations
TL;DR: The seed proteins of ‘Chinese Spring’ wheat stocks which possess single chromosomes from other plant species related to wheat have been separated by gel electrophoresis and support the idea that all these chromosomes are derived from a common ancestral chromosome and that they have maintained their integrity since their derivation from that ancestral chromosome.
Abstract: The seed proteins of ‘Chinese Spring’ wheat stocks which possess single chromosomes from other plant species related to wheat have been separated by gel electrophoresis in the presence of sodium dodecyl sulphate. Marker protein bands have been detected for both arms of barley chromosome 5, chromosome E (= 1R) and B (= 2R) of rye, chromosomes A,B (= 1Cu) and C (= 5Cu) of Aegilops umbellulata and chromosomes I and III of Agropyron elongatum. These studies, and previous findings, indicate that chromosome 5 of barley, chromosome 1R of rye, chromosome I of Ag. elongatum and possibly chromosome 1Cu of Ae. umbellulata are similar to chromosomes 1A, 1B and 1D in hexaploid wheat in that they carry genes controlling prolamins on their short arms and genes controlling high-molecular-weight (apparent molecular weight greater than 86,000) seed protein species on their long arms. These findings support the idea that all these chromosomes are derived from a common ancestral chromosome and that they have maintained their integrity since their derivation from that ancestral chromosome.
192 citations
189 citations
TL;DR: The symbiotic associations of Australian orchids have been examined by isolating Rhizoctonia endophytes from orchid growing in the field and by symbiotic germination of orchid seed.
Abstract: SUMMARY
The symbiotic associations of Australian orchids have been examined by isolating Rhizoctonia endophytes from orchids growing in the field and by symbiotic germination of orchid seed. Many Rhizoctonia isolates fruited and were identified to their perfect states.
The isolation studies showed considerable specificity in association between many orchids and their endophytes. In particular Sebacina vermifera was generally associated with Caladenia and several related genera. Tulasnella calospora was closely associated with Diuris and Orthoceras and it and other species of Tulasnella with Thelymitra and Dendrobium. Ceratobasidium cornigerum was associated with Prasophyllum and Pterostylis and, with other species of Ceratobasidium, with orchids of the subtribe Sarcanthinae. Specificity, however, was not absolute for different Rhizoctonias may occur in an orchid either alone or with the more usual endophyte. A few orchids had a wide range of endophytes commonly present.
Symbiotic germination studies generally substantiated the field isolations but showed further levels of specificity in that isolates of a fungus often differed markedly in their ability to germinate seed of a host or of different hosts under the conditions used.
With orchids specificity seemed to occur at different levels, from species to at least subtribe, though the data are imprecise. If there is specificity to subtribe then there are some anomalies in classification. For instance all Caladeniinae sampled were associated with Sebacina vermifera except Lyperanthus which was associated with a wide range of other fungi. Microtis and Prasophyllum, though not considered closely associated, are placed together in the Prasophyllinae; their endophytes are quite different.
189 citations
TL;DR: The effects of rapid maxillary expansion on the external root structure of thirteen appliance-attached and five unattached maxillary first premolars from nine patients have been investigated with the scanning electron microscope (SEM), and active resorption was the dominant process in anchor premolars extracted almost immediately after rapid expansion.
189 citations
TL;DR: In this article, the authors compared the recoveries and distribution of 15 N in soils (organic N and inorganic N to 90 cm depth), and wheat (grain, straw and roots to 20 cm depth) in areas where rainfall and wheat yields differed greatly.
Abstract: Unground 15 N-labelled medic material ( Medicago littoralis ) was mixed with topsoils at 3 field sites in South Australia, allowed to decompose for about 8 months before sowing wheat, and then for a further 7 months until crop maturity. The site locations were chosen to permit comparisons of recoveries and distribution of 15 N in soils (organic N and inorganic N to 90 cm depth) and wheat (grain, straw and roots to 20 cm depth) in areas where rainfall (and wheat yields) differed greatly. Soils differed also in their texture and organic matter contents. Recoveries of applied 15 N in wheat plus soil were 93.1% from a sandy loam (Caliph) and 92.3% from a sandy soil (Roseworthy) despite differences in rainfall and extent of leaching of the 15 NO 3 − formed from the decomposing medic residues. From a heavy clay soil (Northfield), which received the highest rainfall, the 15 N recovery was 87.7%. The loss of 15 N at this site was not due to leaching, as judged by 15 NO 3 − distribution in the soil profile at seeding and crop maturity. Wheat plants took up only 10.9–17.3% of the 15 N added as legume material. Percentage uptakes of 15 N were not related to grain yields. The proportions of wheat N derived from decomposing medic residues were 9.2% at Caliph (input medic, N, 38 kg N ha −1 ), 10.5% at Roseworthy (input medic N, 57 kg N ha −1 ), and only 4.6% at Northfield (input medic N, 57 kg N ha −1 ). Most (51–70%) of the 15 N recovered in wheat was accounted for in the grain. Inorganic 15 N in the soil profiles was depleted during the cropping phase, and at wheat harvest represented from 0.6 to 3.1% only of 15 N inputs. The major 15 N pool was soil organic 15 N accounting for 71.9–77.7% of 15 N inputs. We conclude that, in the context of N supply from decomposing medic tissues to wheat crops, the main value of the legume is long-term, i.e. in maintaining soil organic N concentrations to ensure adequate delivery of N to future cereal crops. The N of the wheat was not uniformly labelled, root N being generally of the highest atom% enrichmensts, and straw N of the lowest. Nevertheless, at the Roseworthy site, the enrichments of wheat N were similar to those of NO 3 − N in the profile at seeding, indicating that the proportions of 14 N and 15 N in the inorganic N pool did not change appreciably during the cropping period. By assuming equilibrium at this site, we calculate that during 15 months decomposition the soil plus legume delivered about 189 kg N ha −1 , of which 93.2 kg ha −1 (49.3%) was taken up by the wheat, 37.2 kg ha −1 (19.7%) was immobilized or remained as fine root residues, and 17.3 kg ha −1 (9.2%) remained as inorganic N in the soil profile; 41.7 kg ha −1 (22.1%) was unaccounted for in the soil-plant system, and was probably lost via inorganic N. Thus about 6.5 kg inorganic N ha −1 was supplied by the soil plus medic residues per 100 kg dry matter ha −1 removed as wheat grain.
179 citations
TL;DR: The reoccupation of artificially cleared patches in a subtidal epifaunal community was investigated in two field experiments on the pilings of Edithburgh pier, South Austrlia, and a large amount of between-patch variation was found.
Abstract: The reoccupation of artificially cleared patches in a subtidal epifaunal community was investigated in two field experiments on the pilings of Edithburgh pier, South Austrlia. In most cases, the greatest proportion of the patch was reoccupied by the vegetative extension of established sponge and tunicate colonies adjacent to it. Larval recruitment by sponges, bryozoans, tunicates and serpulids contributed to the reoccupation but resulted in only a small proportion of the mean percentage cover. The relative abundances of individual species established in any patch were shown to be a function of the (1) position in space, (2) age, (3) time of creation, (4) initial size of the patch.
175 citations
TL;DR: The sequence of the 247 nucleotide residues of the single strand circular RNA of avocado sunblotch viroid (ASBV) was determined using partial enzymic cleavage methods on overlapping viroid fragments obtained by partial ribonuclease digestion followed by 32p-labelling in vitro at their 5'-ends.
Abstract: The sequence of the 247 nucleotide residues of the single strand circular RNA of avocado sunblotch viroid (ASBV) was determined using partial enzymic cleavage methods on overlapping viroid fragments obtained by partial ribonuclease digestion followed by 32p-labelling in vitro at their 5'-ends. ASBV is much smaller than potato spindle tuber viroid (PSTV; 359 residues) and chrysanthemum stunt viroid (CSV; 356 residues). A secondary structure model for ASBV is proposed and contains 67% of its residues base paired. In contrast to the extensive (69%) sequence homology of CSV with PSTV, only 18% of the ASBV sequence is homologous to PSTV and CSV. There are eight potential polypeptide translation products with chain lengths from 4 to 63 amino acid residues coded for by the plus (infectious) strand and four potential translation products (2 to 60 residues) coded for by the minus strand. An improved method is described for the synthesis of gamma-32p-ATP of high specific activity.
161 citations
TL;DR: It was found that the chemicals caused a severe reduction in flow rates in spite of greatly increased pressure within the system, which supports the hypothesis that ischemia could play an important role in the initiation of ANUG.
TL;DR: In this paper, the authors applied the frequency locus method to the optimization of the spring and damper rates for a dynamic vibration absorber, and derived a tuning function which enables the optimal natural frequency for the absorber to be determined.
TL;DR: In searching the literature for the present paper, it often proved difficult to determine authors' definitions of salinity and brackish water as discussed by the authors, which was especially applicable to articles published early this century which mentioned the presence of ostracods in salt waters and which used the following confusing variety of descriptive terms: "brackish", "high chlorinity", "natron", "mineralized water", or "with high content of salts".
Abstract: In searching the literature for the present paper, it often proved difficult to determine authors’ definitions of salinity and brackish water. This was especially applicable to articles published early this century which mentioned the presence of ostracods in salt waters and which used the following confusing variety of descriptive terms: ‘brackish’, ‘high chlorinity’, ‘natron’, ‘mineralized water’, or ‘with high content of salts’. An additional difficulty was provided by the term ‘coastal pond’: it was usually not stated if the pond was connected to the adjacent sea or not, even if for a short time. Confusion also arose when the authors dealt with forms from the Pontocaspian region, that is the Caspian, Black and Aral Seas; rarely was it clearly stated if the ostracods had actually been collected from these inland seas or from adjacent lagoons (and if these were connected with an inland sea).
TL;DR: Differences in the primary sequence of CSV and PSTV suggest that neither the positive nor putative negative strands of these two viroids code for functional polypeptide products, however, the twoviroids can form similar secondary structures, implicating a role for viroid structure in replication.
Abstract: The sequence of the 356 nucleotide residues of chrysanthemum stunt viroid (CSV) has been determined. Overlapping linear viroid fragments were obtained by partial ribonuclease digestion, radiolabelled in vitro at their 5'-ends, and sequenced using partial enzymic cleavage methods. Of the CSV sequence, 69% is contained in the published sequence of potato spindle tuber viroid (PSTV). Differences in the primary sequence of CSV and PSTV suggest that neither the positive nor putative negative strands of these two viroids code for functional polypeptide products. However, the two viroids can form similar secondary structures, implicating a role for viroid structure in replication.
TL;DR: This study confirms that ultrasonic monitoring provides a reliable measure of follicular growth and allows studies correlating morphological changes with both normal and abnormal endocrine function of the human ovary.
TL;DR: A simple mathematical model of the infection of roots of Trifolium subterraneum by vesicular-arbuscular mycorrhizal fungi is presented and it is suggested that the root tip is nearly 10 times more infectible than the average for the whole root system.
Abstract: Summary
We present a simple mathematical model of the infection of roots of Trifolium subterraneum by vesicular-arbuscular mycorrhizal fungi. The model permits separate calculation of the following.
(1) The frequency of infection in unit length of root in unit time from mycorrhizal propagules distributed uniformly and randomly in soil. A value of 40·8 m−1 day−1 was found for the soil used in the experiments.
(2) The rate of fungal growth along the root cortex from a single entry point, which was found to be 12·2 × 10−4 m day−1 for infections derived from propagules in the same soil.
An alternative method of estimating the frequency of infection close to the root tip (from measurements of the rate of root growth and distance between the apex and the most apical entry-point) is presented. Comparison of values obtained suggests that the root tip is nearly 10 times more infectible than the average for the whole root system.
Some of the assumptions implicit in the model have been investigated experimentally and the results are reported here.
The model should be useful in distinguishing between environmental effects on the phases of colonization occurring in the soil, and at the root surface and within the root.
TL;DR: Protein synthesis and secretion by the epididymis was studied in vitro by incubating tissue pieces with radioactive amino acids or one of a variety of radioactive sugars and protease inhibitors reduced total protein synthesis from SI methionine but did not alter the profile of secreted proteins.
Abstract: Protein synthesis and secretion by the epididymis was studied in vitro by incubating tissue pieces with radioactive amino acids or one of a variety of radioactive sugars. When amino acids were used asprecursors, about 15% of the incorporated radioactivity was released into the medium; the release was 36-65% in the case of sugar precursors. In different regions of the epididymis, pronounced variations were apparent in the profile of secreted proteins formed from amino acids or from galactose, mannose, or fucose. Total protein synthesis as measured by l� 5) methionine incorporation was decreased by ‘\�30% following castration of animals, and the proportion of incorporated radioactivity which was secreted was reduced from 15% to 10%. Only a few qualitative changes were evident in the types of protein secreted. Compared with general protein synthesis, the incorporation of sugars into glycoproteins was affected by castration to a much greater extent, with mannose incorporation being reduced by up to 90% in the cauda. Protease inhibitors (TLCK, TPCK, PMSF, benzamidine, phenanthroline) reduced total protein synthesis from �“ SI methionine but did not alter the profile of secreted proteins. Procaine also reduced total protein synthesis, and in the caput, but not the cauda, it caused a marked change in the pattern of secreted proteins. This differential effect of procaine did not appear to be due to an effect on “signal peptidasc.” Tunicaxnycin had little effect on protein synthesis and secretion by the epididymis when [“SI methionine was used as the precursor, although it did cause pronounced changes in protein secretion by testicular tissue. Greater effects of tunicamycin were evident when radioactive sugars were used as precursors, particularly in the case of [3 HI mannose. The incorporation of this precursor was reduced to 69% and 49% of normal in the caput and cauda, respectively. However, tunicamycin did not alter the profile of secreted radioactive proteins resulting from any of the incubations with radioactive sugars.
TL;DR: In this paper, the ability of a model to describe quantitatively the adsorption of copper, lead and zinc on goethite was tested, and the model was able to describe both the increase in adhesion of metals with increasing pH and the release of protons that accompanied adhesion.
Abstract: The ability of a model to describe quantitatively the adsorption of copper, lead and zinc on goethite was tested. The model was able to describe both the increase in adsorption of metals with increasing pH and the release of protons that accompanied adsorption. For copper and zinc, MeOH+ were the adsorbing species. Part of the increase in adsorption with increasing pH arose because these ions increase in concentration with pH. For lead, Pb2+ ions appeared to be adsorbed, and in this case the increase in adsorption with pH was entirely due to the decreased charge on the surface and thus decreased repulsion. For all three metals, the MeCl+ ions also appeared to be adsorbed, and this explained higher adsorption from chloride solution than from nitrate solutions. The observed release of protons accompanying adsorption was matched by moving the plane of adsorption of metal ions relative to that of the H+ and OH- ions. When the two planes were close, the proton release was almost equivalent to the charge on the metal ions; as the distance increased, proton release decreased.
TL;DR: It is concluded that techniques involving lightness assimilation could provide investigators with a sensitive new method of investigating the specificities of the inhibitory interactions underlying pattern perception.
Abstract: The perceived lightness of grey bars within grey-white and grey-black square-wave test gratings was measured in the presence of different surrounding regions (plain black, plain white, or black-white square-wave gratings). The results for the grey-white test gratings are explained in terms of three separate processes: (i) lightness contrast; (ii) lightness assimilation resulting from the limited ability of the visual system to deal with grating contrast at higher spatial frequencies; and (iii) lightness assimilation resulting from lateral inhibition between pattern detecting channels mediating the perception of the gratings in the test regions and the surrounds. The results for the grey-black test gratings were explained without reference to the third process. It is concluded that techniques involving lightness assimilation could provide investigators with a sensitive new method of investigating the specificities of the inhibitory interactions underlying pattern perception.
TL;DR: Several limnological studies of Australian salt lakes have been made as discussed by the authors, most relate to Victorian waters, but Bayly and De Deckker & Geddes have studied a number of ephemeral salt lakes near the coast of south-eastern South Australia.
Abstract: Several limnological studies of Australian salt lakes have been made. Most relate to Victorian waters (reviewed by Williams 1978), but Bayly (1970) and De Deckker & Geddes (1980) have studied a number of (mostly) ephemeral salt lakes near the coast of south-eastern South Australia. Many similarities occur between lakes in these two regions, the only major differences being the presence of dense angiosperm beds (Ruppia and Lepilaena) and several invertebrates with marine affinities in some of the South Australian lakes.
TL;DR: In this paper, the authors compared the ratio of the pressures required for soil penetration by roots and penetrometers and reported that this ratio can vary from about 2 to 8 depending on conditions.
Abstract: Previous work is reviewed in which the ratio of the pressures required for soil penetration by roots and penetrometers are compared. It appears that this ratio can vary from about 2 to 8 depending on conditions. However, there is very little experimental evidence and most of the work has been inferential. Direct measurements are reported for the stresses exerted by a 1 mm diameter penetrometer probe and by the roots of pea seedlings when penetrating Urrbrae fine sandy loam. Six soil conditions were used: (non-weathered remoulded soil cores + artificially weathered remoulded soil cores + undisturbed field clods) × (confined + unconfined cores or clods). The confinement treatment was to test for any effects of additional restraint to cylindrical root expansion. The weathering and field clod treatments were to test the hypothesis that root elongation is facilitated by tensile failure ahead of the root tip. The principal conclusions are as follows. The laboratory weathering treatment reduced the soil tensile strength by 25%. This resulted in a small but significant reduction in the pressure for root penetration into confined cores. Compared with remoulded non-weathered cores, field clods had a 2 to 3 fold greater penetrometer resistance and a 50% lower tensile strength. The force required for root penetration into unconfined field clods was only 10% greater than for unconfined non-weathered cores. For the former (which is closest to field conditions) the penetrometer had to exert a pressure 5.1 times greater than a root tip in order to penetrate the soil. Penetrometer penetration pressure was independent of probe diameter in the 1–2 mm range in the soil used. Core confinement restricts root radial expansion and modifies the penetration force of metal probes and plant roots. On the basis of the new results it is tentatively concluded that soil tensile failure can facilitate penetration by roots.
TL;DR: Velvet tobacco mottle virus (VTMoV) isolated from Nicotiana velutina growing wild in arid Central Australia was transmitted by inoculation to a limited number of plant species of which N. clevelandii was the most convenient experimental host.
TL;DR: The extent to which presented papers cover the field is determined by the width of the field, participant numbers and, of course, the contents of the papers as mentioned in this paper, which is a common limitation of scientific symposia.
Abstract: Proceedings of specialised scientific symposia are rarely comprehensive. Their usual aim is to provide a record, accessible to a wider audience, of papers read by participants who came together mainly to exchange views, report on their own work, and learn about the work of others. The extent to which presented papers cover the field is determined by the width of the field, participant numbers and, of course, the contents of the papers.
Abstract: A method of time-dependent conformal mapping is introduced to simplify the power-series solution procedure for time- and space-periodic standing waves in deep water. A solution has been found to 25th order in the wave amplitude. The values of certain coefficients are determined by the requirement that secular terms must be suppressed. Because the series for the wave profile is not always uniformly convergent, Pade approximants are used for summation. For very high waves, the slope of the surface has at least two relative maxima. The singularity structure of the solution is also discussed.
TL;DR: The dimensionality and reliability of Rotter's internal-external control scale was examined using Australian students and suggest that the scale is not additive but multidimensional.
Abstract: The dimensionality and reliability of Rotter's internal-external control scale was examined using Australian students. The results imply that the scale is not additive but multidimensional. Two distinct largely independent factors relating to personal and political control beliefs were extracted. General control concerns the belief that a person has mastery over his own life while political control includes items which measure the extent to which an individual is capable. of having an influence on political institutions or the course of world affairs. On retesting, 8 of the 9 General Control items loaded on the same first factor. All 5 of the Political Control items loaded on the second factor. Test-retest reliability of the I-E scale was .61. These results suggest that the Rotter Scale itself, and its two factor structure, are stable over a considerable period of time.
TL;DR: The validity and reliability studies on which it is possible to judge the value of this new test of the clinical competence of medical students when compared to the traditional approach are reported.
Abstract: In a previous study we described a problem-based criterion-referenced test of the clinical competence of medical students which was felt to offer advantages over the traditional final-year examination. This paper reports the validity and reliability studies on which it is possible to judge the value of this new test when compared to the traditional approach. The results demonstrate a high level of content validity and provide evidence of the construct validity of the test. Efforts to obtain measures of concurrent and predictive validity were thwarted by a failure to attain reliable assessments of ward performance from resident and consultant staff. Satisfactory levels of internal consistency were established for the whole test. Marker reliability was satisfactory in all sections of the test except for those requiring examiners to rate practical clinical skills. This was so despite the use of simulated patients, behavioural check-lists and rater training. Possible solutions to this problem are discussed. It is concluded that this new approach overcomes many of the measurement problems inherent in the traditional final examination. It has been shown to be feasible to construct and administer in the medical school setting without the need for the allocation of additional resources.
TL;DR: It is concluded that altered proteins in the tissues are a cause of Chronic inflammation and that, in particular, chronic lymphoedema is a form of chronic inflammation.
Abstract: The subcutaneous tissue of rats was injected with plasma. PVP, or saline. In spite of precautions to avoid immunological reactions and the release of mediators, it was found that the plasma-injected animals had many of the signs of chronic inflammation—even at 64 days. These were considerably reduced by coumarin, a benzo-pyrone, which is known to enhance the lysis of proteins by macrophages. The numbers of these cells were greatly increased in the injection site—especially with the administration of coumarin. PVP also moderately increased macrophage numbers, but did not cause the increase in fibroblast numbers or collagen formation associated with the plasma-injections. It is concluded that altered proteins in the tissues are a cause of chronic inflammation and that, in particular, chronic lymphoedema is a form of chronic inflammation.
TL;DR: Salinarium lakes are of particular interest to limnologists because they encompass a wide range of salinity, differ considerably in morphometry and degree of permanence, and are easily accessible as mentioned in this paper.
Abstract: Although saline lakes are interesting to limnologists, most, unfortunately, are relatively inaccessible. The extent to which they have been studied compared with freshwater lakes is therefore limited. Though not restricted to warm arid regions, they are often numerous in such places, and Australia — not surprizingly — has a large number. Most of these, too, are relatively inaccessible. However, west of Melbourne, Victoria, there are many. They are of particular interest because they encompass a wide range of salinity (3–350‰), differ considerably in morphometry and degree of permanence, and are easily accessible. During the past decade and a half, they have been the focus of studies by several limnologists (mostly with zoological emphasis). These studies were summarily referred to by Williams (1978). The present paper provides a more comprehensive review of most — but not all — of them.
TL;DR: Contractions of the guinea-pig ileum elicited by GABA were reversibly antagonised by various concentrations of picrotoxinin and bicuculline, indicating that the action of GABA in stimulating the intrinsic cholinergic nerves appears to be Cl− dependant.
Abstract: Contractions of the guinea-pig ileum elicited by GABA were reversibly antagonised by various concentrations of picrotoxinin and bicuculline. This antagonism was specific for GABA-induced responses, responses to ACh, BK, and HA being unaffected. The chloride ion channel blockers, furosemide, 2×10−4 mol/l, and piretanide, 5.5×10−5 mol/l, substantially reduced GABA-induced contractions of the ileum but not those elicited by ACh or electrical stimulation of the cholinergic nerves. The action of GABA in stimulating the intrinsic cholinergic nerves appears to be Cl− dependant.