Buttery S H, Lloyd L C, Titchen D A
J Med Microbiol. 1976 Nov;9(4):379-91. doi: 10.1099/00222615-9-4-379.
Twenty of 28 calves, 10-12 weeks of age when given intravenous injections of the galactan from Mycoplasma mycoides subsp. mycoides, showed transient apnoea, increased pulmonary arterial and decreased systemic arterial blood pressures, and increased packed-cell volume. Necropsy revealed haemorrhages associated with alveolar ducts and vessel walls, areas of pulmonary oedema, usually associated with the haemorrhages, dilated airways and, in some, capillary thrombosis. Animals that had shown changes in blood pressure and respiration in response to a dose of galactan did not react to a second dose an hour later. One goat tested died, four lambs were mildly affected and a cat and several rats and guinea-pigs did not respond. It is suggested that the galactan released biogenic amines that produced the effects listed. Immunological mechanisms were discounted on the grounds that only a small amount of antigenic material was injected at the time the reaction occurred, and neither serological nor skin tests produced any evidence of prior sensitisation to the galactan or a similar substance. A relationship between reactivity to the galactan and susceptibility to the natural disease has been suggested. This, together with the pulmonary oedema found in galactan-treated calves and in natural lesions of contagious bovine pleuropneumonia (CBPP), and the possibility that contraction of blood vessels could be an initiating cause of thrombosis indicates the role that galactan may play in the pathogenesis of CBPP.
28头10 - 12周龄的小牛在静脉注射来自丝状支原体丝状亚种的半乳聚糖后，有20头出现了短暂性呼吸暂停、肺动脉压升高、体动脉血压降低以及红细胞压积增加。尸检发现与肺泡管和血管壁相关的出血、通常与出血相关的肺水肿区域、气道扩张，部分还有毛细血管血栓形成。对一定剂量半乳聚糖有血压和呼吸变化反应的动物，一小时后对第二次剂量没有反应。一只受试山羊死亡，四只羔羊受到轻度影响，一只猫以及几只大鼠和豚鼠没有反应。有人认为半乳聚糖释放出生物胺从而产生了上述效应。免疫机制被排除，理由是在反应发生时仅注射了少量抗原性物质，而且血清学和皮肤试验均未产生任何对该半乳聚糖或类似物质先前致敏的证据。有人提出对半乳聚糖的反应性与对自然疾病的易感性之间存在关联。这一点，再加上在接受半乳聚糖治疗的小牛以及传染性牛胸膜肺炎（CBPP）的自然病变中发现的肺水肿，以及血管收缩可能是血栓形成起始原因的可能性，表明半乳聚糖在CBPP发病机制中可能发挥的作用。
