Horm Metab Res 1976; 8(1): 47-50
DOI: 10.1055/s-0028-1093691
Originals

© Georg Thieme Verlag KG Stuttgart · New York

Impairment and Restoration of Response to TSH in Dog Thyroid Slices after Treatment with Phospholipase A and Lubrol PX

K.  Yamashita1 , H.  Oka2 , T.  Kaneko2 , E.  Ogata1
  • 1Section of Endocrinology and Metabolism, Department of Medicine, University of Tsukuba
    School of Medicine, Niiharigun, Ibaraki Pref., Japan
  • 2First Department of Medicine, University of Tokyo School of Medicine, Tokyo, Japan
Further Information

Publication History

Publication Date:
23 December 2008 (online)

Abstract

Incubation of dog thyroid slices with phospholipase A (10- 40 u/ml) or Lubrol PX (0.08-0.4%) caused a diminution in the subsequent TSH effect on the tissue cyclic AMP level and glucose oxidation. The same treatment had no effect on the basal level of these parameters.

When the phospholipase A or Lubrol PX-treated slices were rinsed intensively with a Krebs-Ringer bicarbonate buffer and then incubated at 37°C in the same buffer for a further 1 to 3 hours, responsiveness to TSH recovered progressively reaching almost completely that of the control slices. Again, these procedures were without any significant effect on the responsiveness of the control slices.

The above results together with those reported previously suggest strongly that phospholipids are an essential component of the plasma membrane system by which TSH stimulates adenylate cycles activity. In addition, these essential lipids in the membrane appear to be renewed rather efficiently in this tissue, thus securing the functional integrity of the thyroid in the face of various deleterious situations.

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