Diethylaminoethanol action in the arthritis with Freund adjuvant, in rats

The authors have studied the action of diethylaminoethanol on Freund adjuvant arthritis, induced in female Lewis rats. They worked on 3 groups, each one including 14 rats, weighing 110-130 g: group I = control; group II = rats injected intracutaneous with 0.1 ml Freund adjuvant; group III = rats injected with Freund adjuvant and treated with diethylaminoethanol i.m. (10 mg/kg body weight), and gel application (2.5%) on paws and tail, daily. During the experiment clinical observations and measurements were made and when the animals were killed, blood was sampled for haematological and immunological assays (CD4, CD8, CD25 T cells and NK cells, antinuclear autoantibody and immune complexes). While in all the rats from group II (without treatment) inflammatory processes developed at the level of the peripheral joints, in group III (diethylaminoethanol treated), these ones were present in only 64% of the rats and by much more reduced forms, followed by a short period of involution. The paw volume, measured with an electronic plethysmometer, was more reduced in the treated rats (7.1-14.2%) than in the non treated ones (27.7-29.3%). The haematologic examination showed an increased number of neutrophiles in both groups with FA injecting. The immunological investigations revealed: a decrease of CD4 cells and an increase of CD8 T cells and NK cells in both groups, a much more decreased level (13.2%) of circulatory immune complexes in treated rats, as compared to the non-treated ones (71.7%). No differences were found regarding the CD25 cells and antinuclear antibodies. The histo-pathological examination showed that the intensity and the extension area of the joint lesions (granulation tissue with fibrous change, cartilage invasion and dilaceration, bone atrophy) were much more reduced in the treated rats. The authors put forward the hypothesis that these effects might be due to diethylaminoethanol antiinflammatory properties.