Determination of gangliosides in human cerebrospinal fluid by high-performance thin-layer chromatography and direct densitometry

A method for the separation and quantification of a complex ganglioside mixture from a clinically available amount (5 ml) of human cerebrospinal fluid (CSF) is described. After reduction of the CSF volume by ultrafiltration, gangliosides are extracted with methanol/chloroform, then separated and quantified by high performance thin layer chromatography (HPTLC) and direct densitometry. For purification of crude ganglioside extract, the method of choice was microdialysis against water. Recovery for the present method including all methodological steps was 78%. No delective loss of gangliosides was demonstrated. The CSF ganglioside pattern from 'normal' CSF samples resembles that of brain gangliosides, particularly cerebellum gangliosides. Based on chromatographic comparison with standards, the percentages of lipid-bound NeuAc-positive fractions were: GM1 = II3NeuAc-GgOse4Cer (3%), GD3 = II3NeuAc2-Lac-Cer (3%), GD1a = IV3NeuAc,II3NeuAc-GgOse4Cer (15%), X1 (3%), GD1b = II3(NeuAc)2-GgOse4Cer (16%), X2 (3%), GT1b = IV3NeuAc,II3NeuAc2-GgOse4-Cer (41%), and GQ1b = IV3NeuAc2-,II3NeuAc2-GgOse4-Cer (16%). The total ganglioside content varied between 616-944 micrograms/l. Within-run and between-run assay precision (relative standard deviation) for 'normal' pooled CSF ranged from 0.04 to 0.12 for the predominant CSF ganglioside fractions (GD1a, GD1b, GT1b, GQ1b), and from 0.13 to 0.23 for the less pronounced fractions (GM1, GD3).     

Diagnostic value of ganglioside patterns in plasma of human diseases

A method that could be facilitated for the quantitation and qualitation of gangliosides in human plasma was developed and applied in the present study for characterization of ganglioside patterns in plasmas of patients with neoplastic diseases including gastric cancer, adult T-cell leukemia (ATL), and acute lymphocytic leukemia (ALL). As a retrovirus-infected disease with different clinical entity, human T-cell lymphotropic virus type I-associated myelopathy (HAM) was also subjected to this study. The results were compared with the patterns obtained from normal control plasmas. The analytical data revealed that GM3 increased in gastric cancer, GT1b decreased in HAM and ATL, and GD3, GM1 and GM3 decreased in ALL. There were close correlations between various human diseases and the presence of gangliosides with their specific patterns. Furthermore, gangliosides purified from plasma of patients with HAM significantly inhibited the expression of CD4 antigen on human T lymphocyte membrane. Therefore, analytical studies of plasma gangliosides could provide diagnostic and therapeutic values in retroviral infections.     

Internalization of exogenous gangliosides in cultured skin fibroblasts for the diagnosis of mucolipidosis IV

The internalization of exogenous mixed brain gangliosides in ML IV cultured skin fibroblasts indicated an impairment of ganglioside catabolism in these cells. Incubation of ML IV, normal and various other lysosomal storage disorders cell lines for five days with exogenous tritium labelled GM3, GD1a or GT1 gangliosides allowed accurate quantitation of the retained gangliosides. This in vitro approach provides a reliable method for the diagnosis of ML IV.     

Ganglioside loading of cultured fibroblasts: a provocative method for the diagnosis of the GM2 gangliosidoses

Confirmation of deficient beta-hexosaminidase activity in suspected cases of GM2 gangliosidosis may be difficult with available assay systems if the residual activity is high (as in many juvenile cases and genetic compounds). Hexosaminidase activity is normal in the AB-variant (activator protein deficiency), although GM2-ganglioside (GM2) catabolism is severely impaired. We therefore examined ganglioside degradation in intact fibroblasts in culture. Intracellular ganglioside levels were determined in cultured human skin fibroblasts grown in standard tissue culture medium or medium supplemented with mixed bovine brain gangliosides. Cellular uptake and catabolism of the added gangliosides were manifested by modest increases in the intracellular concentrations of gangliosides GT + GD and GM1 in all cells tested, and marked accumulation of GM2 in fibroblasts from patients with GM2 gangliosidoses. Intracellular GM2 increased five- to fifteen-fold in all of the GM2 gangliosidosis cell lines tested, including those from patients with infantile Tay-Sachs disease (TSD), Sandhoff disease, late infantile and juvenile variants of TSD with high residual enzyme activity, adult onset GM2 gangliosidosis, and the AB-variant. Significant GM2 accumulation did not occur in fibroblasts from patients with GM2 gangliosidosis grown in standard medium, or in normal fibroblasts grown in ganglioside enriched medium. Our method of ganglioside feeding employs commercially available materials and no special equipment. It should be useful for the confirmation of impaired GM2 catabolism in a variety of settings.     

Amplified ELISA to detect autoantibodies to N-glycolyl-GM3 ganglioside

Numerous immunochemical methods are now available for the detection of antibodies to gangliosides. An amplified ELISA method for detection of autoantibodies to NGcGM3 ganglioside in the sera of patients with various type of renal diseases was developed. IgM antibodies were found in 39 out of 53 sera of patients using 30 normal healthy blood donor as a negative control. For human IgG conjugate no reactivity to NGcGM3 was seen in the sera. Positive ELISA results were confirmed by TLC-immunostaining using GM3, NGcGM3, NGcGM2 and Standard bovine gangliosides (GM1, GD1a, GD1b and GT1b). All sera were also assayed for reactivity with GM3 in ELISA to determine the line specificity of these antibodies. Based on these results, a protocol for a sensitive and reproducible amplification ELISA system for serum anti-NGcGM3 antibodies in patients with renal or other diseases is presented. The ELISA method described here in appear to be useful adjunt to measure antiNGcGM3 antibodies in sera of patients with various type of renal or other diseases.     

GD3, a prominent ganglioside of human melanoma. Detection and characterisation by mouse monoclonal antibody

Mouse monoclonal antibody AbR24 has a high degree of specificity for human melanoma cells when tested on viable cultured cells using the protein A mixed hemagglutinin serological assay. The antigen detected by this antibody has been isolated from melanoma cells and shown to be GD3 ganglioside by compositional and partial structural analysis and by comparison with authentic GD3 in thin layer chromatography (TLC). AbR24 reacts with authentic GD3, but not with any other ganglioside tested. Using TLC and reactivity with AbR24, a wide range of cells and tissues was examined for the presence of GD3. A new serological assay, termed glycolipid-mediated immune adherence, was devised for assaying the reactivity of AbR24 with gangliosides. Melanomas (cultured cells or tumor tissue) were shown to have GD3 and GM3 as major gangliosides. Other cells and tissues examined also contained GD3, but usually only in low amounts. Melanomas (and MOLT-4, a T cell line) were characterized by a simplified ganglioside profile with GD3 and GM3 as major components. The apparent discrepancy between the ubiquitous presence of GD3 and the serological specificity of AbR24 for melanoma cells can be explained in terms of localization and concentration of GD3 in different cells.     

Further study on cerebral sphingolipids including gangliosides in two cases of juvenile amaurotic family idiocy (Spielmeyer-Vogt type) using a new analytical procedure of sphingolipids.

Sphingolipids isolated from cerebral grey and white matter of two patients with Juvenile Amaurotic Idiocy (Spielmeyer-Vogt Type) were studied. A new analytical procedure was attempted for the determination of sphingolipids, i.e., cerebroside, sulfatide, sphingomyelin and gangliosides were subjected to ozonolysis and reduced with NaBH4. Fatty alcohols thus derived from the double bond-containing long chain bases of the sphingolipids were analyzed by GLC as their TMS-derivatives using an internal standard. The new procedure was suitable for the analysis of small amounts of sphingolipids and could determine the amounts of C18 and C20 sphingosines. It was found that all individual gangliosides in both cases gave lower proportions of C20 sphingosine to the total long chain bases. Sphingomyelin in normal human grey matter contained a small but significant amount of C20 sphingosine, while the sphingomyelin of the two patient brains indicated a much lower proportion of C20 sphingosine in comparison with those of age-matched controls. Thus, this disease seemed to be related to a genetical defect in the metabolic regulation of the long chain bases of gangliosides and grey matter sphingomyelin. On the other hand, it was noted that the ganglioside pattern of grey matter in case-1 was entirely different from that of case-2. The grey matter gangliosides in case-1 were composed of 1.78% of GM2, 81.19% of GM1 and 17.02% of GD1b by the amounts of long chain bases, while the grey matter gangliosides in case-2 seemed to be similar to those of normal human brains. Also, unusual fatty acid compositions of galactosphingolipids (cerebrosides and sulfatides) were observed to a somewhat extent in the grey matter of case-1.     

Hemolysis of human erythrocytes is a new bioactivity of gangliosides.

Using sheep erythrocytes and liposomes, an inhibitory effect of gangliosides has been shown on the activation of the alternative pathway of complement. However, in studies using human erythrocytes, we found that gangliosides had hemolytic activity that was possibly mediated through activation of the alternative pathway. Pretreatment of human erythrocytes obtained from healthy volunteers or paroxysmal nocturnal hemoglobinuria (PNH) patients with a ganglioside mixture purified from human erythrocytes enhanced their susceptibility to homologous human complement, and resulted in dose-dependent hemolysis. The enhancement was more marked in PNH erythrocytes than control cells. Protease treatment of the ganglioside mixture did not change its hemolytic activity, but sialidase treatment abolished the activity. Among the major erythrocyte gangliosides, II3NeuAc-LacCer (GM3) was the most potent hemolytic agent. Gangliosides purified from bovine brain were also active, while neither nonsialylated glycosphingolipids, the ceramide moiety, or sialic acid alone were active. Sialic acid residues in the ganglioside molecules were essential to this activity, but the amount of the residue or the source of the gangliosides seemed not to be important. Several treatments inhibiting the alternative but not classical complement pathway markedly reduced the ganglioside hemolytic activity. This novel bioactivity of gangliosides was thus suggested to be mediated partly by activation of the alternative pathway.     

Cross-presentation of disialoganglioside GD3 to natural killer T cells

GD3, a ganglioside expressed on human melanoma, can be recognized by the humoral immune system. In this paper, we demonstrate that immunizing mice with the human melanoma cell line SK-MEL-28 (GD3+ GM2- CD1-) or with syngeneic APCs loaded with GD3 can induce a GD3-reactive natural killer T (NKT) cell response. GD3-reactive NKT cells were detected among splenocytes of immunized mice at frequencies of approximately 1:2000 both by ELISPOT and GD3-loaded mouse CD1d tetramer analysis. GD3-reactive NKT cells did not react with GM2, a closely related ganglioside, and were not detectable in unimmunized mice. GD3-reactive NKT cells initially produced IL-4 and IFN-gamma followed by IL-10. They were CD1d restricted in that reactivity was abrogated when APCs were blocked with anti-CD1d monoclonal antibody before being loaded with GD3 or when APCs from CD1d knockout mice were used. Because SK-MEL-28 does not express any isoform of human CD1, GD3 must be cross-presented by murine APCs in vivo. This is the first analysis of a natural ligand for mouse NKT cells and the first definitive paper of cross-presentation to NKT cells. This could be a mechanism for NKT cell recognition of tumor gangliosides in CD1- tumors.     

Induction of IgG antibodies against GD3 ganglioside in rabbits by an anti-idiotypic monoclonal antibody.

Anti-idiotypic MAb were raised in syngeneic mice against a mouse MAb recognizing GD3 ganglioside (MAb R24). Two anti-idiotypic MAb, designated BEC2 and BEC3, recognized distinct determinants on MAb R24 that mapped near or within the GD3-binding site. New Zealand white rabbits, which express GD3 on normal tissues, were immunized with either BEC2, BEC3, or control MAb FLOPC-21. All rabbits developed high and equivalent titers of antibodies against mouse immunoglobulins. Immunization with BEC2 and BEC3 induced rabbit antibodies expressing R24 idiotype as demonstrated by their ability to inhibit BEC2 binding to R24. Antibodies (IgG and IgM) reacting with GD3 developed in five of eight rabbits immunized with BEC2 but not in rabbits immunized with BEC3 or with control MAb. Serum antibodies against GD3 did not cross-react with other gangliosides. These results show that MAb BEC2 can mimic GD3 ganglioside and can induce antibodies against GD3 ganglioside despite expression of GD3 on normal rabbit tissue.     

Compositional changes in brain lipids, especially cerebroside and gangliosides, of rats treated with methylmercury chloride

Rats were orally given 4 mg of methylmercury chloride per kg per day up to 14 days, and killed at 4-day or arbitrary intervals. Parietal gray matter and cerebellum were taken for lipid analyses. The ganglioside content increased during the early stage before the manifestation of clinical symptoms. After the onset of clinical signs, the total lipid concentration was elevated, and especially the levels of phosphatidylethanolamine and cerebroside were increased. The ganglioside distribution patterns were also altered in the late stage, showing decreased proportion of GD1a and increased percentages of GD1b and GQ1b.     

Determination of gangliosides and sulfatide in human cerebrospinal fluid with a microimmunoaffinity technique

An immunostaining procedure has been developed for the assay of the gangliotetraose gangliosides and sulfatide in cerebrospinal fluid. Gangliosides of the gangliotetraose series were individually determined with cholera toxin B-subunit (CT-B) and an anti CT-B monoclonal antibody after chromatography and sialidase hydrolysis to GM1 on high performance thin-layer plates. Sulfatide was determined by thin-layer chromatography using an anti-sulfatide antibody. The method was applied to normal cerebrospinal fluid from 20 adults and 30 children. The concentration of the gangliotetraose series gangliosides in adults varied from 100-300 nmol/l with a mean value of 230 +/- 56 nmol/l. Corresponding values for sulfatide were 30-225 nmol/l and 140 +/- 46 nmol/l. The values for gangliosides and sulfatide in children increased during development. The major gangliosides in cerebrospinal fluid of adults were GT1b and GD1b and in children GD1a and GT1b.     

Ganglioside agglutination immunoassay for rapid detection of autoantibodies in immune-mediated neuropathy

Elevated levels of serum autoantibodies directed against gangliosides are closely associated with acute and chronic autoimmune neuropathies. An agglutination immunoassay using polystyrene microparticles coated with a total extract of brain gangliosides was used to test patient sera for the presence of anti-ganglioside antibodies. Results were compared with those obtained by ELISA for anti-GM1 and anti-GQ1b ganglioside antibodies. Eight of the twelve sera from patients with multifocal motor neuropathy and seven of the thirteen sera from patients with Guillain-Barré syndrome were positive for the presence of anti-ganglioside antibodies by the ganglioside agglutination immunoassay. The assay compared favorably with the ELISA system in sensitivity and specificity, while requiring a fraction of the time and cost to perform. The new assay can serve as a rapid and effective method for detecting or screening for anti-ganglioside antibodies in patients with acute or chronic immune-mediated neuropathies. It would be particularly useful for detecting antibodies that react with multiple gangliosides, or with minor or as yet uncharacterized gangliosides.     

Monoclonal antibodies raised against Guillain-Barré syndrome–associated Campylobacter jejuni lipopolysaccharides react with neuronal gangliosides and paralyze muscle-nerve preparations

Guillain-Barré syndrome and its variant, Miller-Fisher syndrome, are acute, postinfectious, autoimmune neuropathies that frequently follow Campylobacter jejuni enteritis. The pathogenesis is believed to involve molecular mimicry between sialylated epitopes on C. jejuni LPSs and neural gangliosides. More than 90% of Miller-Fisher syndrome cases have serum anti-GQ1b and anti-GT1a ganglioside antibodies that may also react with other disialylated gangliosides including GD3 and GD1b. Structural studies on LPS from neuropathy-associated C. jejuni strains have revealed GT1a-like and GD3-like core oligosaccharides. To determine whether this structural mimicry results in pathogenic autoantibodies, we immunized mice with GT1a/GD3-like C. jejuni LPS and then cloned mAb's that reacted with both the immunizing LPS and GQ1b/GT1a/GD3 gangliosides. Immunohistology demonstrated antibody binding to ganglioside-rich sites including motor nerve terminals. In ex vivo electrophysiological studies of nerve terminal function, application of antibodies either ex vivo or in vivo via passive immunization induced massive quantal release of acetylcholine, followed by neurotransmission block. This effect was complement-dependent and associated with extensive deposits of IgM and C3c at nerve terminals. These data provide strong support for the molecular mimicry hypothesis as a mechanism for the induction of cross-reactive pathogenic anti-ganglioside/LPS antibodies in postinfectious neuropathies.     

短暂性全脑缺血再灌注大鼠经高压氧治疗后脑组织神经节苷脂的变化

背景:神经节苷脂是神经组织中含量丰富并可发挥神经保护作用的含唾液酸的鞘糖脂,在脑缺血或缺氧性疾患时有含量或组分的变化。目的:通过观察全脑缺血再灌注大鼠应用高压氧治疗后脑组织神经节苷脂的变化情况,探讨高压氧对缺血再灌注损伤治疗作用的可能途径。设计:随机-对照观察。单位:首都医科大学附属朝阳医院高压氧科和首都医科大学基础医学院生物化学与分子生物学系。材料:动物模型制作于2002-03/04在首都医科大学附属朝阳医院高压氧科(北京市重点实验室)完成,各项指标检测在首都医科大学基础医学院生物化学与分子生物学系完成。选择雌性SD大鼠54只,将大鼠随机分成9组,即假手术组、缺血再灌注6h,24h,48h,96h组及高压氧6h,24h,48h,96h组,每组6只。方法:除假手术组外,其余8组大鼠均建立脑缺血再灌注动物模型,按四动脉阻断法建立,缺血20min后再通。假手术组同样手术但不阻断动脉。将高压氧组大鼠置于实验舱内,纯氧洗舱5min,升压5min至0.1MPa后稳压,吸纯氧45min,减压10min。高压氧组大鼠在缺血再灌注3h后行高压氧处理1次,24h,48h及96h组在每天同一时间行高压氧处理1次。缺血再灌注组和假手术组处于常压空气环境中。再灌注组和高压氧处理组大鼠分别于再灌注6h,24h,48h及96h麻醉取全脑标本测定总神经节苷脂及各组分百分含量,神经节苷脂各组分以高效薄层层析法测定。主要观察指标:各组大鼠全脑组织神经节苷脂的总含量及其各组分的百分含量。结果:54只大鼠全部进入结果分析,无脱失。①高压氧24h及48h组总神经节苷脂均显著高于假手术组及相应缺血再灌注时相组(F=12.730,122.246,P<0.01),但缺血再灌注各时相组与假手术组相比,差异均无显著性意义(P>0.05)。②对缺血再灌注24h组大鼠GT1b相对含量显著低于假手术组(F=13.575,P<0.01),再灌注48h组GD1b及GM1分别低于假手术组(F=4.015,3.979,P<0.05),GM3于再灌注24h高于假手术组及其他时相组(F=21.450,P<0.01),并于再灌注96h反弹。③高压氧24h组GM1,GM3分别高于假手术组(F=3.970,21.450,P<0.05,<0.01),GD1a、GD1b和GT1b均低于假手术组(F=13.575,5.745,8.783,P<0.05～0.01),但GT1b明显高于缺血再灌注各相应时相组(F=8.783,P<0.05)。结论:大鼠短暂全脑缺血再灌注后可引起神经节苷脂总含量、GT1b,GD1b,GM1百分含量降低及GM3百分含量升高,其中提高脑组织神经节苷脂总量、GM1含量及加速GT1b的恢复可能为高压氧治疗改善缺血性脑损伤的作用途径,而GD1a,GD1b百分含量的下降有何作用尚不清楚。     

Intraplantar injection of gangliosides produces nociceptive behavior and hyperalgesia via a glutamate signaling mechanism

Gangliosides are abundant in neural tissue and play important roles in cell-cell adhesion, signal transduction, and cell differentiation. Gangliosides are divided into 4 groups: asialo-, a-, b-, and c-series gangliosides, based on their biosynthetic pathway. St8sia1 knockout mice, which lack b- and c-series gangliosides, exhibit altered nociceptive responses. The mechanism underlying this defect, however, remains unclear. To address this issue, we first investigated the possibility that gangliosides in peripheral nociceptor endings are involved in nociception. Intraplantar injection of the b-series ganglioside GT1b, but not a-series gangliosides such as GM1, produced nociceptive responses and enhanced low-concentration formalin-induced nociception. N-methyl-d-aspartic acid receptor and type I metabotropic glutamate receptor antagonists inhibited GT1b-induced hyperalgesia, suggesting the involvement of glutamate receptors. Furthermore, microdialysis analysis revealed elevated glutamate content in subdermal tissues due to intraplantar injection of GT1b. Co-injection of glutamate dehydrogenase with GT1b attenuated GT1b-induced hyperalgesia. These findings suggested that GT1b induced extracellular glutamate to accumulate in subdermal tissues, thereafter activating glutamate receptors, which in turn resulted in hyperalgesia and nociception. On the other hand, intraplantar injection of sialidase, which cleaves sialyl residues from glycoconjugates such as gangliosides, attenuated the late phase of 2% formalin-induced nociception. Thus, the antinociceptive effects of sialidase and the nociceptive effects of GT1b indicated that endogenous gangliosides are involved in nociceptive responses. These results suggest that gangliosides play important roles in nociceptive responses originating in peripheral nociceptor endings.     

Cryoprecipitation of an anti-Pr2 monoclonal IgM cold agglutinin in the presence of GM3 ganglioside.

The mechanism of cryoprecipitation of a monoclonal IgM kappa cryoglobulin (Mou) with a cold agglutinin activity of Pr2 specificity has been studied. By immunodiffusion this cryoglobulin reacted (by its Fab' fragment) with micellar GM3, a ganglioside bearing the Pr2 antigenic determinant. In contrast to previous reports that indicated a possible temperature dependent self-association of IgM molecules via an immunological interaction leading to cold precipitation, we could not detect any affinity of this cryoglobulin for IgM when we used passive hemagglutination or an indirect enzyme-linked immunosorbent assay (ELISA). However, a GM3-like ganglioside could be extracted, by drastic methods, from the cryoglobulin studied at 22 degrees C, whereas no GM3 was extracted from two control cryoglobulins. Some minor gangliosides (representing less than 25% of total amount of bound gangliosides) were also extracted from Mou cryoglobulin and these gangliosides were shown to crossreact with GM3, as they specifically bind to Mou cryoglobulin by ELISA. After cryoprecipitation the serum still contained a monoclonal anti-Pr2 IgM kappa. A GM3-like ganglioside could be extracted from this purified IgM, and cryoprecipitability could be induced by the addition of a minute amount of micellar GM3. These results suggest that Mou cryoglobulin circulates as an immune complex and that cryoprecipitation may depend on unique IgM-GM3 (or IgM-GM3 cross-reacting gangliosides) complexes.     

Inverse relationship of expression between GM3 and globo-series ganglioside in human renal cell carcinoma

Renal cell carcinoma (RCC) is highly metastatic. We previously showed that expression of globo-series ganglioside is associated with the metastatic potential of RCC. However, the mechanism of metastasis remains largely unknown, and there is no effective therapy for metastasis. It was recently shown that induction of differentiation of colon cancer cells by brefeldin A was accompanied by an increase of GM3 with a concomitant decrease of neolacto-series gangliosides. To get a clue to a new method of therapy for RCC, we investigated whether the similar changes occur in RCC cells expressing globo-series ganglioside. Growth suppression and an increase of GM3 simultaneous with a decrease of monosialosyl galactosyl globoside, a member of globo-series gangliosides, were observed in human RCC cell line ACHN following brefeldin A treatment. The resultant change of the ganglioside profile is inversely related to the ganglioside pattern associated with the malignant potential of RCC and almost coincided with that representative of RCC cases showing favorable prognoses. It is suggested that the inverse relationship of expression between GM3 and globo-series ganglioside is reflected on the degree of malignancy of RCC, and may be useful as one of the indicators for exploiting treatment methods of RCC.     

Gangliosides as markers for murine lymphocyte subpopulations

Antibodies to GM1 ganglioside were used to study murine lymphocyte populations. In A, AKR, and BALB/c mice, anti-GM1 reacts with thymocytes and peripheral T cells. This reactivity of anti-GM1, studied by immunofluorescence, is independent of Thy-1 type and appears to be related to the reactivity of cross-reacting antibodies to asialo GM1 and GD1b, rather than GM1 itself. In addition, a subpopulation of lymphocytes reacting with anti-GM1 and anti-immunoglobulin has been found in approximately 26% of the peripheral lymphocytes of C3H mice, nude mice, and nude heterozygotes. This subpopulation is found in small numbers in A, AKR, and BALB/c mice. These studies demonstrate that antibodies to a chemically defined antigen can be used to identify T cells in many strains of mice and may delineate previously unrecognized lymphocyte subpopulations.     

Gangliosides and thermal adaptation in vertebrates.

Gangliosides, which are highly enriched in synaptic membranes, show great differences in concentration and pattern constellation as well during early ontogenetical development as on interspecies level in vertebrates. As, up to now, there is no reasonable explanation for these findings, and as it is assumed the synapse to be the primary site of thermal adaptation, the attempt was made to investigate whether there are any correlations between brain gangliosides and the thermal adaptation phenomenon. 1. While in the brains of adult homeothermic vertebrates (with thermo-regulation: mammals, birds) the di-sialoganglioside GD1a predominates, in the brain of poikilotherms (without thermo-regulation: e.g. amphibia, teleost fishes) more polar polysialogangliosides are present. 2. In homeotherms during their early perinatal phase (heterothermic phase: thermor-regulation being not yet developed) a temporary poly-sialisation of brain-gangliosides occurs. 3. In poikilotherms, during the process of thermal adaptation to lowered environmental temperatures, a poly-sialisation of brain gangliosides can be observed, as well during the phase of acclimatization (adaptation to seasonal changes in temperature) as also to acclimation (experimentally induced changes in the environmental temperature). 4. The phenomenon of poly-sialisation of brain gangliosides during adaptation to lowered environmental temperatures can be correlated with changes in some behavioral (e.g. motorical activity) and electrophysiological parameters. 5. On the background of a general hypothesis on the involvement of gangliosides in the process of transmission [23, 24], a functional model on the participation of gangliosides in the process of thermal adaptation is discussed with special regard to the formation of Ca++-ganglioside-complexes, which are highly sensitive to temperature changes.